U.S. patent application number 15/103116 was filed with the patent office on 2016-12-08 for electronic control unit, electric power steering device, and vehicle.
The applicant listed for this patent is NSK Ltd.. Invention is credited to Yoshikatsu INADA, Takaaki SEKINE, Kotaro TAGAMI.
Application Number | 20160355210 15/103116 |
Document ID | / |
Family ID | 53370878 |
Filed Date | 2016-12-08 |
United States Patent
Application |
20160355210 |
Kind Code |
A1 |
INADA; Yoshikatsu ; et
al. |
December 8, 2016 |
Electronic Control Unit, Electric Power Steering Device, and
Vehicle
Abstract
An electronic control unit, an electric power steering device,
and a vehicle are provided, such that the power loss from output
terminals of two power modules including first and second power
modules to the electric current joining point is suppressed. The
electronic control unit includes an input and output board
connected with the first and second power modules. First and second
conductor patterns respectively connected with output terminals of
the first and second power modules and extending independently of
each other are formed in the input and output board. A terminal is
mounted on the output connector, the terminal including first and
second board connection portions respectively connected with the
first and second conductor patterns.
Inventors: |
INADA; Yoshikatsu;
(Fujisawa-shi, Kanagawa, JP) ; TAGAMI; Kotaro;
(Fujisawa-shi, Kanagawa, JP) ; SEKINE; Takaaki;
(Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NSK Ltd. |
Shinagawa-ku, Tokyo |
|
JP |
|
|
Family ID: |
53370878 |
Appl. No.: |
15/103116 |
Filed: |
December 12, 2014 |
PCT Filed: |
December 12, 2014 |
PCT NO: |
PCT/JP2014/006200 |
371 Date: |
June 9, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02P 27/06 20130101;
H05K 7/20854 20130101; B62D 5/0463 20130101; B62D 5/0406 20130101;
H02K 11/33 20160101; H05K 7/1432 20130101; B62D 5/0457
20130101 |
International
Class: |
B62D 5/04 20060101
B62D005/04; H02K 11/33 20060101 H02K011/33; H02P 27/06 20060101
H02P027/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 13, 2013 |
JP |
2013-258298 |
Dec 13, 2013 |
JP |
2013-258299 |
Dec 13, 2013 |
JP |
2013-258300 |
Dec 13, 2013 |
JP |
2013-258301 |
Dec 20, 2013 |
JP |
2013-263957 |
Dec 20, 2013 |
JP |
2013-263958 |
Dec 20, 2013 |
JP |
2013-263959 |
Dec 20, 2013 |
JP |
2013-263960 |
Claims
1. An electronic control unit comprising: first and second power
modules on which switching elements are respectively mounted; an
input and output board on which an input connector and an output
connector to be connected to an electric motor are mounted, and
which is connected with the first and second power modules; and a
control board on which a controller configured to control output
currents from the first and second power modules, wherein first and
second conductor patterns respectively connected with output
terminals of the first and second power modules and extending
independently of each other are formed in the input and output
board, and wherein a terminal is mounted on the output connector,
the terminal comprising: an output terminal portion to be connected
to the electric motor; and first and second board connection
portions extending from the output terminal portion to be
respectively connected to the first and second conductor
patterns.
2. The electronic control unit according to claim 1, wherein the
first and second conductor patterns are arranged to be
line-symmetric when the first and second conductor patterns are
viewed from a plane of the input and output board.
3. The electronic control unit according to claim 1, wherein a
first output terminal of the first power module comprises a first
A-phase output terminal, a first B-phase output terminal, and a
first C-phase output terminal respectively corresponding to an A
phase, a B phase, and a C phase of the electric motor, wherein a
second output terminal of the second power module comprises a
second A-phase output terminal, a second B-phase output terminal,
and a second C-phase output terminal respectively corresponding to
the A phase, the B phase, and the C phase of the electric motor,
wherein the first conductor pattern comprises a first A-phase
conductor pattern connected with and extending from the first
A-phase output terminal of the first power module, a first B-phase
conductor pattern connected with and extending from the first
B-phase output terminal of the first power module, and a first
C-phase conductor pattern connected with and extending from the
first C-phase output terminal of the first power module, and
wherein the second conductor pattern comprises a second A-phase
conductor pattern connected with and extending from the second
A-phase output terminal of the second power module, a second
B-phase conductor pattern connected with and extending from the
second B-phase output terminal of the second power module, and a
second C-phase conductor pattern connected with and extending from
the second C-phase output terminal of the second power module.
4. The electronic control unit according to claim 3, wherein the
terminal comprises an A-phase terminal, a B-phase terminal, and a
C-phase terminal respectively corresponding to the A phase, the B
phase, and the C phase of the electric motor, wherein the A-phase
terminal comprises the output terminal portion, the first board
connection portion to be connected to the first A-phase conductor
pattern, and the second board connection portion to be connected to
the second A-phase conductor pattern, wherein the B-phase terminal
comprises the output terminal portion, the first board connection
portion to be connected to the first B-phase conductor pattern, and
the second board connection portion to be connected to the second
B-phase conductor pattern, and wherein the C-phase terminal
comprises the output terminal portion, the first board connection
portion to be connected to the first C-phase conductor pattern, and
the second board connection portion to be connected to the second
C-phase conductor pattern.
5. The electronic control unit according to claim 4, wherein the
A-phase terminal, the B-phase terminal, and the C-phase terminal
are insert-molded to be insulated from each other and overlap each
other, when a housing is formed.
6. The electronic control unit according to claim 4, wherein the
first and second board connection portions of the A-phase terminal,
the first and second board connection portions of the B-phase
terminal, and the first and second board connection portions of the
C-phase terminal are arranged to be line-symmetric when viewed from
a plane of the output connector.
7. An electric power steering device comprising the electronic
control unit according to claim 1.
8. A vehicle comprising the electric power steering device
according to claim 7.
9. The electronic control unit according to claim 2, wherein a
first output terminal of the first power module comprises a first
A-phase output terminal, a first B-phase output terminal, and a
first C-phase output terminal respectively corresponding to an A
phase, a B phase, and a C phase of the electric motor, wherein a
second output terminal of the second power module comprises a
second A-phase output terminal, a second B-phase output terminal,
and a second C-phase output terminal respectively corresponding to
the A phase, the B phase, and the C phase of the electric motor,
wherein the first conductor pattern comprises a first A-phase
conductor pattern connected with and extending from the first
A-phase output terminal of the first power module, a first B-phase
conductor pattern connected with and extending from the first
B-phase output terminal of the first power module, and a first
C-phase conductor pattern connected with and extending from the
first C-phase output terminal of the first power module, and
wherein the second conductor pattern comprises a second A-phase
conductor pattern connected with and extending from the second
A-phase output terminal of the second power module, a second
B-phase conductor pattern connected with and extending from the
second B-phase output terminal of the second power module, and a
second C-phase conductor pattern connected with and extending from
the second C-phase output terminal of the second power module.
10. The electronic control unit according to claim 5, wherein the
first and second board connection portions of the A-phase terminal,
the first and second board connection portions of the B-phase
terminal, and the first and second board connection portions of the
C-phase terminal are arranged to be line-symmetric when viewed from
a plane of the output connector.
Description
TECHNICAL FIELD
[0001] The present invention relates to an electronic control unit
(ECU: Electronic Control Unit), an electric power steering, and a
vehicle, in particular, to an electronic control unit configured to
control driving of an electric motor, an electric power steering
device using the same, and a vehicle in which the electric power
steering is equipped.
BACKGROUND ART
[0002] The electronic control unit in the electric power steering
device equipped in a vehicle controls driving of the electric
motor, and includes a power module equipped with switching
elements, and a control board on which a control device of
controlling an output current from the power module is implemented.
The power module is electrically connected with the electric motor
via an output connector, and the control board is electrically
connected with the battery and the torque sensor of the
vehicle.
[0003] In this situation, even if an abnormality occurs at the
switching element (switching means) of the power module in the ECU
of driving the electric motor, there is a demand for continuing of
the driving of the electric motor.
[0004] To meet this demand, the electric power steering device of
Patent Literature 1 is conventionally proposed.
[0005] In the electric power steering device of Patent Literature
1, multi-phase motor winding of the electric motor is duplicated,
for example, and each of inverter units supplies the electric
current to each of the duplicated multi-phase motor windings. That
is, a first inverter unit supplies the electric current to one of
the multi-phase motor windings, whereas a second inverter unit
supplies the electric current to the other one of the multi-phase
motor windings.
[0006] Then, when the switching means (i.e., switching element) of
one of the inverter units (e.g., the first inverter unit)
encounters an off failure to be non-conductive, that is an open
failure, the switching means suffering from the failure is
identified, the switching means other than the failed switching
means is controlled, and the normal inverter unit (e.g., the second
inverter unit) is controlled other than the failed inverter unit
(e.g., the first inverter unit) including the failed switching
means.
CITATION LIST
Patent Literature
[0007] PLT 1: JP 4998836 B
SUMMARY
Technical Problem
[0008] The above-described electric power steering device of PLT 1,
however, has a following drawback.
[0009] That is, PLT 1 does not disclose at all anything about the
actual wiring from the first inverter unit that supplies the
electric current to one of the multi-phase motor windings, or the
actual wiring from the second inverter unit that supplies the
electric current to the other one of the multi-phase motor
windings.
[0010] In detail, PLT 1 does not disclose at all a pattern
configuration connecting from the first and second inverter units
to the electric motor in the circuit board connected with the first
and second inverter units, or does not disclose the output
connector configuration at all. Hence, depending on the pattern
configuration or the three-phase output connector configuration,
the power loss from the output units of the first and second
inverter units to the electric current joining point might be
increased.
[0011] Accordingly, the present invention has been made to address
the above drawbacks, and has an object to provide an electronic
control unit configured to control driving of an electric motor, an
electric power steering device using the same, and a vehicle in
which the electric power steering is equipped. In the electronic
control unit, by designing the pattern configuration and the
connector configuration of an input and output board to be
connected with two power modules including first and second power
modules on each of which switching elements are mounted, the power
loss from output terminals of the first and second power modules to
electric current joining points can be suppressed.
Solution to Problem
[0012] In order to address the above drawback, according to one
aspect of the present invention, there is provided an electronic
control unit including: first and second power modules on which
switching elements are respectively mounted; an input and output
board on which an input connector and an output connector to be
connected to an electric motor are mounted, and which is connected
with the first and second power modules; and a control board on
which a controller configured to control output currents from the
first and second power modules. First and second conductor patterns
respectively connected with output terminals of the first and
second power modules and extending independently of each other are
formed in the input and output board, and a terminal is mounted on
the output connector, the terminal including: an output terminal
portion to be connected to the electric motor; and first and second
board connection portions extending from the output terminal
portion to be respectively connected to the first and second
conductor patterns.
[0013] In addition, according to yet another aspect of the present
invention, there is provided an electric power steering device
including the above-described electronic control unit.
[0014] Further, according to yet another aspect of the present
invention, there is provided a vehicle including the
above-described electric power steering device.
Advantageous Effects
[0015] According to an electronic control unit, an electric power
steering device, and a vehicle in one embodiment of the present
invention, first and second conductor patterns are provided to be
respectively connected with output terminals of first and second
power modules and extend independently of each other, such that
motor drive currents respectively output from the output terminals
of the first and second power modules flow in two lines across the
first and second conductor patterns independently of each other in
the input and output board. In addition, the output connector
includes a terminal including an output terminal portion to be
connected to the electric motor, and first and second board
connection portions extending from the output terminal portion to
be connected respectively to the first and second conductor
patterns. Hence, the motor drive currents flow across the first and
second conductor patterns in two lines independently of each other,
then flow through the first and second board connection portions of
the terminal independently of each other, and join at the output
terminal portion to be connected to the electric motor. Therefore,
the motor drive currents join at the output terminal portions
closest to the electric motor. This configuration makes longer the
distances between the output terminals of the first and second
power modules and the electric current joining point than the
distance in a case where the electric currents are joined on the
input and output board. Hence, the power loss from the first and
second power modules to the electric current joining point is
suppressed. Since the power loss is proportional to the square of
the electric current value, a shorter distance through which such a
heavy current flows after the electric currents are joined may be
desirable.
BRIEF DESCRIPTION OF DRAWINGS
[0016] FIG. 1 is a view of a basic configuration of an electric
power steering device in which an electronic control unit operating
as a motor controller in some embodiments of the present
invention;
[0017] FIG. 2 is a block diagram illustrating a control system of
the motor controller of the electric power steering device
illustrated in FIG. 1;
[0018] FIG. 3 is an exploded perspective view of an inner
configuration of the electric control unit operating as the motor
controller;
[0019] FIG. 4 is a perspective view of an outer configuration of
the electric control unit;
[0020] FIG. 5 is a first side view of the electric control unit
when viewed from an arrow L1 direction;
[0021] FIG. 6 is a second side view of the electric control unit
when viewed from an arrow L2 direction;
[0022] FIG. 7 is a perspective view of a power module of FIG.
3;
[0023] FIG. 8 is a view of the power module when viewed from an
arrow L3 direction of FIG. 7;
[0024] FIG. 9 is a cross-sectional view schematically illustrating
an outline configuration of a housing;
[0025] FIG. 10 is a perspective view of an input and output board
of the electric control unit on which a power supply input
connector, a three-phase output connector, and electronic parts
(i.e., discrete parts) are mounted;
[0026] FIG. 11 is a front view of the input and output board when
viewed from an arrow L4 direction of FIG. 10;
[0027] FIG. 12 is a side view of the input and output board when
viewed from an arrow L5 direction of FIG. 10 (i.e., an identical
direction to the arrow L1 direction);
[0028] FIG. 13A is a plan view of an A-phase terminal included in a
terminal used for the three-phase output connector, when viewed in
an arrow L6 direction of FIG. 10;
[0029] FIG. 13B is a side view of the A-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L5 direction of FIG. 10;
[0030] FIG. 13C is a front view of the A-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L4 direction of FIG. 10;
[0031] FIG. 14A is a plan view of a B-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L6 direction of FIG. 10;
[0032] FIG. 14B is a side view of the B-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L5 direction of FIG. 10;
[0033] FIG. 14C is a front view of the B-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L4 direction of FIG. 10;
[0034] FIG. 15A is a plan view of a C-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L6 direction of FIG. 10;
[0035] FIG. 15B is a side view of the C-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L5 direction of FIG. 10;
[0036] FIG. 15C is a front view of the C-phase terminal included in
the terminal used for the three-phase output connector, when viewed
in the arrow L4 direction of FIG. 10;
[0037] FIG. 16 is a perspective view of the input and output board
and the control board connected by first and second power modules,
and the power supply input connector, the three-phase output
connector, and the electronic parts (i.e., discrete parts)
illustrated in FIG. 10 are mounted on the input and output
board;
[0038] FIG. 17 is a plan view of the input and output board and the
control board when viewed from an arrow L8 direction of FIG. 16
(i.e., an identical direction to the arrow L6 direction); and
[0039] FIG. 18 is a side view of the input and output board and the
control board when viewed from an arrow L7 direction of FIG. 16
(i.e., an identical direction to the arrow L5 direction).
DESCRIPTION OF EMBODIMENTS
[0040] Hereinafter, embodiments of the present invention will be
described with reference to the accompanied drawings.
[0041] FIG. 1 is a view of a basic configuration of an electric
power steering device in which an electronic control unit operating
as a motor controller in some embodiments of the present
invention.
[0042] The electric power steering device illustrated in FIG. 1 is
equipped in a vehicle like an automobile. In such an electric power
steering device, a steering force exerted by a driver to a steering
wheel 1 is transmitted to a steering shaft 2. The steering shaft 2
includes an input shaft 2a and an output shaft 2b. One end of the
input shaft 2a is coupled with the steering wheel 1, whereas the
other end thereof is coupled through a steering torque sensor 3
with the outer end of the output shaft 2b.
[0043] Then, the steering force that has been transmitted to the
output shaft 2b is transmitted via a universal joint 4 to a lower
shaft 5, and is further transmitted to a pinion shaft 7 via a
universal joint 6. The steering force that has been transmitted to
the pinion shaft 7 is transmitted to a tie rod 9 via a steering
gear 8, so that turning wheels, not illustrated, are made to turn.
Here, the steering gear 8 is configured to be a rack and pinion
form including a pinion 8a connected with the pinion shaft 7 and a
rack 8b engaging with the pinion 8a, and the rotational motion that
has been transmitted to the pinion 8a is converted at the rack 8b
into the straight motion of the vehicle widthwise direction.
[0044] The output shaft 2b of the steering shaft 2 is coupled with
a steering assistance mechanism 10 that transmits a steering
assistance force to the output shaft 2b. The steering assistance
mechanism 10 includes a reduction gear 11 including, for example, a
worm gear mechanism connected with the output shaft 2b, and an
electric motor 12 operating as the electric motor including, for
example, a three-phase brushless motor producing the steering
assistance force and connected with the reduction gear 11.
[0045] The steering torque sensor 3 detects steering torque exerted
onto the steering wheel 1 and then transmitted to the input shaft
2a. The steering torque sensor 3, for example, converts the
steering torque into a twisting angular displacement of a torsion
bar (not illustrated) arranged between the input shaft 2a and the
output shaft 2b, and to convert the twisting angular displacement
into an angle difference between an input-side rotational angle
sensor (not illustrated) arranged on the input shaft 2a side and an
output side rotational angle sensor (not illustrated) arranged on
the output shaft 2b side.
[0046] In addition, the electric motor 12 is configured with, for
example, a three-phase brushless motor, and as illustrated in FIG.
2, motor windings La, Lb, and, Lc of A phase, B phase, and C phase
of the three phases are respectively wound around slots of the
stator. One ends of the motor windings La, Lb, and Lc of the
respective phases are connected together to form a star connection,
whereas the other ends of the motor windings La, Lb, and Lc of the
respective phases are connected with a motor controller 20, so that
motor drive currents Ia, Ib, and Ic are individually supplied.
[0047] The electric motor 12, as illustrated in FIG. 2, includes a
rotational position sensor 13a configured to detect the rotational
position of the motor. The detection value from the rotational
position sensor 13a is supplied to a motor rotational angle
detection circuit 13, so that the motor rotational angle detection
circuit 13 detects a motor rotational angle .theta.m.
[0048] In addition, a direct current is input into the motor
controller 20 from a battery 22 operating as a direct current power
source.
[0049] Herein, as illustrated in FIG. 2, the motor controller 20
includes a control operation device 31 configured to operate
three-phase voltage instruction values V1* and V2*, first and
second motor drive circuits 32A and 32B into which the three-phase
motor voltage instruction values V1* and V2* output from the
control operation device 31 are individually input, and first and
second motor current cutoff circuits 33A and 33B respectively
arranged between the first and second motor drive circuits 32A and
32B and the motor windings La, Lb, and Lc of the respective phases
of the electric motor 12.
[0050] The control operation device 31 receives a steering torque
detected by the steering torque sensor 3, a vehicle speed detected
by a vehicle speed sensor 21, and a motor rotational angle .theta.m
output from the motor rotational angle detection circuit 13, a
motor angular velocity, and a motor angular acceleration. In
addition, the control operation device 31 receives motor drive
currents I1a to I1c and I2a to I2c, output from current detection
circuits 39A and 39B, and supplied to the motor windings La, Lb,
and Lc of the respective phases of the electric motor 12. Then, the
control operation device 31 calculates the three-phase voltage
instruction values V1* and V2* corresponding to the first and
second motor drive circuits 32A and 32B based on the steering
torque, the vehicle speed, the motor rotational angle .theta.m, the
motor angular velocity, and the motor angular acceleration, and
then outputs the calculated three-phase voltage instruction values
V1* and V2* to gate drive circuits 41A and 41B, as will be
described later, of the first and second motor drive circuits 32A
and 32B.
[0051] Then, the control operation device 31 includes an
abnormality detection unit 31a configured to detect an open failure
of the upper arms and a short-circuit failure of the lower arms of
field effect transistors (FET) Q1 to Q6 operating as switching
elements included in first and second inverter circuits 42A and
42B, as will be described later, and a disconnection abnormality of
any of the coil units of the motor windings La, Lb, and Lc of the
respective phases of the electric motor 12. When the abnormality
detection unit 31a does not detect an open failure or a
short-circuit failure of the field effect transistors (FET) Q1 to
Q6, the abnormality detection unit 31a outputs failure detection
signals SAa and SAb of logical values "0" (normality) to the gate
drive circuits 41A and 41B of the first and second motor drive
circuits 32A and 32B, whereas when the abnormality detection unit
31a detects the open failure and the short-circuit failure of the
field effect transistors (FET) Q1 to Q6, the abnormality detection
unit 31a outputs a failure detection signals SAa or SAb of a
logical value "1" (abnormality) to the gate drive circuit 41A or
41B of the first and second motor drive circuit 32A or 32B where
the abnormality has been detected.
[0052] Each of the first and second motor drive circuits 32A and
32B receives the three-phase voltage instruction values V1* and V2*
output from the control operation device 31, and forms a gate
signal, and includes gate drive circuits 41A and 41B also operating
as abnormality time current controllers, and first and second
inverter circuits 42A and 42B that receive gate signals output from
the gate drive circuits 41A and 41B.
[0053] Here, when the failure detection signal SAa input from the
control operation device 31 is the logical value "0" (normality),
the gate drive circuit 41A is configured to output three gate
signals of high level to the motor current cutoff circuit 33A, and
output the gate signal of high level to a power cutoff circuit 44A.
In addition, when the failure detection signal SAa is the logical
value "1" (abnormality), the gate drive circuit 41A is configured
to output three gate signals of low level to the motor current
cutoff circuit 33A at the same time to cut off motor drive currents
I1a to I1c, and output the gate signal of low level to the power
cutoff circuit 44A to cut off a battery current.
[0054] Similarly, when the failure detection signal SAa input from
the control operation device 31 is the logical value "0"
(normality), the gate drive circuit 41B is configured to output
three-gate signals of high level to the motor current cutoff
circuit 33B, and output the gate signal of high level to a power
cutoff circuit 44B. In addition, when the failure detection signal
SAa is the logical value "1" (abnormality), the gate drive circuit
41B is configured to output three gate signals of low level to the
motor current cutoff circuit 33B at the same time to cut off motor
drive currents I2a to I2c, and output the gate signal of low level
to the power cutoff circuit 44B to cut off a battery current.
[0055] Further, each of the first and second inverter circuits 42A
and 42B receives a battery current of a battery 22 through a noise
filter 43 and the power cutoff circuits 44A and 44B, and is
respectively connected on the input side with electrolytic
capacitors CA and CB for smoothing.
[0056] Then, each of the first and second inverter circuits 42A and
42B includes six field effect transistors (FETs) Q1 to Q6 operating
as switching elements, and has a configuration in which three
switching arms SAa, SAb, and SAc are connected in parallel and two
FETs are connected in series in each of three switching arms SAa,
SAb, and SAc. Then, the FETs Q1 to Q6 included in the first
inverter circuit 42A receive the gate signals output from the gate
drive circuit 41A, and the motor drive current I1a of A phase, the
motor drive current I1b of B phase, and the motor drive current I1c
of C phase are supplied from between the FETs in each of the
switching arms SAa, SAb, and SAc through the motor current cutoff
circuit 33A to the motor windings La, Lb, and Lc of the respective
phases of the electric motor 12. Further, the FETs Q1 to Q6
included in the second inverter circuit 42B receive gate signals
output from the gate drive circuit 41B, and the motor drive current
I2a of A phase, the motor drive current I2b of B phase, and the
motor drive current I2c of C phase are electrically conductive from
between the FETs in each of the switching arms SAa, SAb, and SAc
through the motor current cutoff circuit 33B to the motor windings
La, Lb, and Lc of the respective phases of the electric motor
12.
[0057] It is to be noted that the motor current cutoff circuit 33A
includes three FETs QA1 to QA3 for cutting off the current, and the
motor current cutoff circuit 33B includes three FETs QB1 to QB3 for
cutting off the current.
[0058] Then, the source of the FET QA1 of the motor current cutoff
circuit 33A is connected with a connection point of transistors Q1
and Q2 of the switching arm SAa of the first inverter circuit 42A,
and the drain of the FET QA1 is connected with the A-phase motor
winding La of the electric motor 12. Further, the source of the FET
QA2 is connected with a connection point of transistors Q3 and Q4
of the switching arm SAb of the first inverter circuit 42A, and the
drain of FET QA2 is connected with the B-phase motor winding Lb of
the electric motor 12. Furthermore, the source of the FET QA3 is
connected with a connection point of transistors Q5 and Q6 of the
switching arm SAc of the first inverter circuit 42A, and the drain
of the FET QA3 is connected with the C-phase motor winding Lc of
the electric motor 12.
[0059] In addition, the source of the FET QB1 of the motor current
cutoff circuit 33B is connected with a connection point of the
transistors Q1 and Q2 of the switching arm SBa of the second
inverter circuit 42B, and the drain of the FET QB1 is connected
with the A-phase motor winding La of the electric motor 12.
Further, the source of the FET QB2 is connected with a connection
point of the transistors Q3 and Q4 of the switching arm SBb of the
second inverter circuit 42B, and the drain of the FET QB2 is
connected to the B-phase motor winding Lb of the electric motor 12.
Furthermore, the source of the FET QB3 is connected with a
connection point of the transistors Q5 and Q6 of the switching arm
SBc of the second inverter circuit 42B, and the drain of the FET
QB3 is connected to the C-phase motor winding Lc of the electric
motor 12.
[0060] Thus, wiring from the drain of the FET QA1 of the motor
current cutoff circuit 33A and wiring from the drain of the FET QB1
of the motor current cutoff circuit 33B are connected and joined
with the A-phase motor winding La of the electric motor 12. Also,
wiring from the drain of FET QA2 of the motor current cutoff
circuit 33A and wiring from the drain of FET QB2 of the motor
current cutoff circuit 33B are connected and joined with the
B-phase motor winding Lb of the electric motor 12. Further, wiring
from the drain of the FET QA3 of the motor current cutoff circuit
33A and wiring from the drain of the FET QB3 of the motor current
cutoff circuit 33B are connected and joined with the C-phase motor
winding Lc of the electric motor 12.
[0061] Next, a configuration of an electronic control unit 50
operating as the motor controller 20 will be described by using
FIG. 3 to FIG. 9.
[0062] In FIG. 3 to FIG. 9, mainly, the electronic control unit 50
includes first and second power modules 60A and 60B, an input and
output board 70, a control board 80, and a housing 90 configured to
accommodate them.
[0063] The first power module 60A includes the motor current cutoff
circuit 33A, a first inverter circuit 42A including plural
switching elements, and a power cutoff circuit 44A. The second
power module 60B includes, mainly, the motor current cutoff circuit
33B, a second inverter circuit 42B including plural switching
elements, and a power cutoff circuit 44B.
[0064] The input and output board 70 includes a power supply input
connector (an input connector) 71 to which the power is input, a
three-phase output connector (an output connector) 100 of making an
output to the electric motor 12, and electronic parts (discrete
parts) 73 such as electrolytic capacitors CA and CB, coils 73a and
73b included in a noise filter 43, resistors, and a three-terminal
regulator 73.
[0065] The control board 80 includes the control operation device
31 operating as a controller of controlling output currents from
the first and second power modules 60A and 60B, a gate drive device
82A equipped with the gate drive circuit 41A, a gate drive device
82B equipped with the gate drive circuit 41B, and electronic parts
such as capacitors, resistors, and a signal input connector 81. The
input and output board 70 has a multilayer interconnection
structure in which wiring layers are arranged on, for example, a
top face 70d and a bottom face 70e, or on the top face 70d, the
bottom face 70e, and an inner layer. The control board 80 has a
multilayer interconnection structure in which wiring layers are
arranged, for example, on a top face 80b and a bottom face 80c, or
on the top face 80b, the bottom face 80c, and an inner layer. The
interconnection structure extending between output terminals 66A
and 66B of the first and second power modules 60A and 60B in the
input and output board 70 (see FIG. 17) and the three-phase output
connector 100 will be described later in detail.
[0066] The housing 90 mainly includes a case 91 and a cover 95,
such that the first and second power modules 60A and 60B, the input
and output board 70, and the control board 80 are accommodated in
an accommodation portion including the case 91 and the cover 95.
The case 91 and the cover 95 are made of an electrically conductive
material, for example, Aluminum Die Cast (ADC).
[0067] The case 91 has a depressed shape including a ceiling 92, a
side wall 93 integrally arranged at the edge of the ceiling 92 to
surround the center of the ceiling 92, and an opening portion
arranged on the opposite side to the ceiling 92. The cover 95 is
attached to cover the opening portion. The case 91 is formed to
have a substantially rectangular shape in a plane view, and
includes four side walls 93 (93a, 93b, 99c, and 93d). In the four
side walls 93a, 93b, 93c, and 93d, the two side walls 93a and 93b
face each other in a first direction (left-right direction), and
the other two side walls 93c and 93d face each other in a second
direction (front-rear direction) perpendicular to the first
direction.
[0068] The first and second power modules 60A and 60B are
individually screwed and secured to the two side walls 93c and 93d
facing each other of the case 91 with screw members 65 from the
inside. In addition, the input and output board 70 is screwed and
secured to the ceiling 92 of the case 91 with a screw member 75
from the inside. Further, the control board 80 is screwed and
secured to the ceiling 92 of the case 91 with screw members 85 from
the inside. Furthermore, the cover 95 is screwed and secured to the
side walls 93a, 93b, 93c, and 93d of the case 91 with screw members
96 from its outer side. The input and output board 70 and the
control board 80 face each other with a predetermined space D (see
FIG. 9) in a thickness direction of the electronic control unit 50,
that is an up-down direction. In FIG. 3, the input and output board
70 is arranged above the control board 80 with the top being set to
"up" and the bottom being set to "down".
[0069] The three-phase output connector 100 mounted on the input
and output board 70 is exposed outwardly from the side wall 93a of
the case 91 (see FIG. 4 and FIG. 5). In addition, the power supply
input connector 71 of the input and output board 70 and the signal
input connector 81 of the control board 80 are exposed outwardly
from the side wall 93b of the case 91 (see FIG. 6). A detailed
configuration of the three-phase output connector 100 will be
described later.
[0070] As illustrated in FIG. 7 and FIG. 8, each of the first and
second power modules 60A and 60B includes a seal body 61, plural
first leads 63, and plural second leads 64. Each of the first and
second power modules 60A and 60B has a package structure of a
bidirectional lead array type.
[0071] The seal body 61 is formed to have a rectangular plane shape
in a plane view, and is formed in rectangular having, for example,
two long sides 61a and 61b and two short sides 61c and 61d in one
embodiment of the present invention. The seal body 61 is made of,
for example, an insulating resin or ceramics. The seal body 61 of
the first power module 60A mainly seals the switching elements
included in the first inverter circuit 42A. The seal body 61 of the
second power module 60B mainly seals the switching elements
included in the second inverter circuit 42B.
[0072] Plural first and second leads 63 and 64 are not illustrate
in detail, but they extend over the inside and outside of the seal
body 61, and includes an inner lead part located at the inside of
the seal body 61 and an outer lead part located at the outside of
the seal body 61.
[0073] Each of the plural first leads 63 extends along one long
side 61a of two long sides 61a and 61b of the seal body 61, at the
outer lead part located at the outside of the seal body 61. Each of
plural second leads 64 along the other one long side 61b of the two
long sides 61a and 61b of the seal body 61, at the outer lead part
located at the outside of the seal body 61.
[0074] Each of the plural first and second leads 63 and 64 is
formed by bending in plural steps at the outer lead part located at
the outside of the seal body 61.
[0075] Each of the outer lead parts of the plural first leads 63 is
formed by bending, for example, in three steps, including a first
part 63a that protrudes from one long side 61a of the seal body 61,
a second part 63b that bends in a thickness direction of the seal
body 61 from the first part 63a, and a third part 63c that bends to
a back face side of the seal body 61 from this second part 63b.
[0076] Each of the outer lead parts of the plural second leads 64
is formed by bending, for example, in two steps, including a first
part 64a that protrudes from the other long side 61b of the seal
body 61, and a second part 64b that bends to slant toward a back
face side of the seal body 61 from the first part 64a.
[0077] In the first and second power modules 60A and 60B, each of
the plural first leads 63 are, for example, soldered onto the
wiring of the input and output board 70 and connected electrically
and mechanically. In addition, each of the plural second leads 64
are, for example, soldered onto the wiring of the control board 80
and connected electrically and mechanically.
[0078] Here, the plural first leads 63 include the first lead 63
electrically connected to a terminal of the power supply input
connector 71 and the first lead 63 electrically connected to a
terminal of the three-phase output connector 100, through electric
wiring of the input and output board 70. In addition, the plural
second leads 64 include the second lead 64 electrically connected
to a terminal of the signal input connector 81 through electric
wiring of the control board 80.
[0079] It is to be noted that the first lead 63 electrically
connected to the terminal of the three-phase output connector 100
in the first power module 60A operates as an output terminal 66A of
the first power module 60A (see FIG. 17), and the first lead 63
electrically connected to the terminal of the three-phase output
connector 100 in the second power module 60B operates as an output
terminal 66B of the second power module 60B (see FIG. 17).
[0080] The electronic control unit 50 configured as described above
is attached at an end face on the opposite side of an output shaft
12a of the electric motor 12, and is screwed and secured with a
screw member, not illustrated. On the bottom face of the cover 95
included in the electronic control unit 50, as illustrated in FIG.
3 to FIG. 6, plural boss portions 95b are formed to protrude. In
attaching the electronic control unit 50 onto the electric motor
12, the boss portions 95b are mounted on plural first attachment
flange portions 12b arranged on the electric motor 12, and in
addition, the bottom face of the cover 95 is mounted on an end face
on the opposite side to the output shaft 12a. Then, by screwing and
securing the first attachment flange portions 12b and the boss
portions 95b with screw members, not illustrated, the electronic
control unit 50 is attached onto the electric motor 12. It is to be
noted that plural second attachment flange portions 12c for
attaching other members are provided on the output shaft 12a side
of the electric motor 12.
[0081] Next, a manufacturing method (assembling method) of the
electronic control unit 50 will be described with reference to FIG.
3.
[0082] Firstly, the first and second power modules 60A and 60B, the
input and output board 70, the control board 80, the case 91, and
the cover 95 are prepared. On the input and output board 70, the
electronic parts (discrete parts) 73 such as the power supply input
connector 71, the three-phase output connector 100, the
electrolytic capacitors CA and CB, the coils 73a and 73b included
in the noise filter 43, the resistors, and the three-terminal
regulator are mounted. On the control board 80, electronic parts
such as the control device (control operation device 31) that
controls output currents from the first and second power modules
60A and 60B, and the gate drive device (gate drive circuits 41A and
41B) are mounted. Further, the electronic parts such as the
capacitors, the resistors, and the signal input connector 81 are
mounted.
[0083] Next, the first and second power modules 60A and 60B are
individually screwed and secured onto the side walls 93c and 93d of
the case 91 with screw members 65 from the inside. Then, the input
and output board 70 is screwed and secured onto the ceiling 92 of
the case 91 with the screw members 75 from the inside. The input
and output board 70 includes plural screw through holes 70c. In
screwing and securing, the screw members 75 are respectively
inserted through the screw through holes 70c. In addition, when the
input and output board 70 is screwed and secured onto the ceiling
92 of the case 91, plural first leads 63 of the first and second
power modules 60A and 60B are inserted into through holes (not
illustrated) arranged in the wiring of the input and output board
70.
[0084] Next, the control board 80 is screwed and secured onto the
ceiling 92 of the case 91 with the screw members 85 from the
inside. The control board 80 includes plural screw through holes
80a. In screwing and securing, the screw members 85 are
respectively inserted into the screw through holes 80a. Further,
when the control board 80 is screwed and secured onto the ceiling
92 of the case 91, the plural second leads 64 of the first and
second power modules 60A and 60B are inserted into through holes
(not illustrated) arranged in the wiring of the control board
80.
[0085] Then, plural first leads 63 of the first and second power
modules 60A and 60B are electrically and mechanically connected to
the through holes arranged in the input and output board 70 by
soldering, and at the same time, the plural second leads 64 of the
first and second power modules 60A and 60B are electrically and
mechanically connected to the through holes arranged in the control
board 80 by soldering.
[0086] Then, the cover 95 is attached to cover the opening of the
case 91, and is screwed and secured to the side wall 93 of the case
91 with screw members 96 from the outside of the cover 95. Plural
screw through holes 95a are arranged in the cover 95, and in
screwing and securing, the screw members 96 are respectively
inserted into the through holes 95a.
[0087] Accordingly, the electronic control unit 50 in one
embodiment of the present invention is almost produced.
[0088] In the electronic control unit 50, as illustrated in FIG. 9,
the input and output board 70 and the control board 80 are arranged
to face each other with a predetermined space D in a direction of
the thickness of the electronic control unit 50, that is in the
up-down direction. In one embodiment of the present invention, the
input and output board 70 is arranged closer to the ceiling 92 of
the case 91 than to the control board 80, the control board 80 is
arranged closer to the cover 95 than to the input and output board
70, that is, arranged on the lower side.
[0089] The input and output board 70 is formed to have a plane size
that is smaller than the plane size of the control board 80. The
input and output board 70 has two sides 70a and 70b facing each
other, and the control board 80 has two sides 80aa and 80bb facing
each other.
[0090] One side 70a of the input and output board 70 is located on
the same side with one side 80aa of the control board 80, and is
located on an inner side than the one side 80aa. The other side 70b
of the input and output board 70 is located on the same side with
the other side 80bb of the control board 80, and is located on an
inner side than the other side 80bb.
[0091] The first power module 60A is arranged to intersect one side
70a of the input and output board 70 on the one sides 70a and 80aa
side of the input and output board 70 and the control board 80. The
second power module 60B is arranged to intersect one side 70b of
the input and output board 70 on the other sides 70b and 80bb side
of the input and output board 70 and the control board 80.
[0092] As described above, the electronic parts 73 mounted on the
input and output board 70 are discrete parts including, for
example, electrolytic capacitors CA and CB, the coils 73a and 73b
included in the noise filter 43, the resistors, and the
three-terminal regulators. Among these discrete parts, the
electrolytic capacitors CA and CB, the coils 73a and 73b included
in the noise filter 43 are relatively higher electronic parts 73.
In other words, a height H1 of the coil 73a, a height H2 of the
coil 73b, and a height H3 of the electrolytic capacitors CA and CB,
which are the electronic parts 73 considered to be relatively high,
as illustrated in FIG. 11, are larger than a half, which is D/2, a
distance D between the input and output board 70 and the control
board (see FIG. 9).
[0093] The discrete parts such as the coils 73a and 73b and the
electrolytic capacitors CA and CB, which are the electronic parts
73 considered to be relatively high are mounted only on a face of
the input and output board 70 facing the control board 80, that is,
only on the bottom face 70e of the input and output board 70. As
illustrated in FIG. 10 and FIG. 11, the electronic parts 73 are not
mounted on a top face 70d of the input and output board 70, the top
face 80b of the control board 80, or the bottom face 80c of the
control board 80.
[0094] Thus, the discrete parts which are the electronic parts 73
considered to be relatively high are mounted only on a face of the
input and output board 70 facing the control board 80, that is,
only on the bottom face 70e of the input and output board 70.
Accordingly, the height size of the electronic control unit 50 can
be lowered without limiting the mounting arrangement of the input
and output board 70 or the control board 80 facing each other in
the up-down direction.
[0095] In other words, by mounting the discrete parts that are
electronic parts 73 considered to be relatively high on a face (the
bottom face 70e) of the input and output board 70 facing the
control board 80, a space between the input and output board 70 and
the control board 80 can be utilized for the mounting of the
discrete parts of the electronic parts 73 considered to be
relatively high, and the size of the electronic control unit 50 can
be lowered. Also, when the arrangements of the above-described
discrete parts are divided into the face (the bottom face 70e) of
the input and output board 70 facing the control board 80 and the
face (the top face 80b) of the control board 80 facing the input
and output board 70, the height of the electronic control unit 50
can be lowered. However, such a configuration brings an
inconvenience of limiting the mounting arrangements of the input
and output board 70 and the control board 80 in order to avoid a
contact between the discrete parts arranged on both of the input
and output board 70 and the control board 80.
[0096] Next, configurations of the output terminals 66A and 66B of
the first and second power modules 60A and 60B in the input and
output board 70, wiring structures between the output terminals 66A
and 66B and the three-phase output connector 100, and a
configuration of the three-phase output connector 100 will be
described with reference to FIG. 10 to FIG. 18.
[0097] Firstly, the output terminal 66A of the first power module,
as illustrated in FIG. 16 and FIG. 17, includes a first A-phase
output terminal 66Aa, a first B-phase output terminal 66Ab, and a
first C-phase output terminal 66Ac, respectively corresponding to
the A phase, B phase, and C phase of the electric motor 12. In
addition, the output terminal 66B of the second power module 60B,
as illustrated in FIG. 16 and FIG. 17, includes a second A-phase
output terminal 66Ba, a second B-phase output terminal 66Bb, and a
second C-phase output terminal 66Bc, respectively corresponding to
the A phase, B phase, and C phase of the electric motor 12.
[0098] Further, first and second conductor patterns 76A and 76B are
formed on the input and output board 70, as illustrated in FIG. 17,
such that the first and second conductor patterns 76A and 76B are
respectively connected to the output terminals 66A and 66B of the
first and second power modules 60A and 60B, and extend
independently of each other.
[0099] Here, the first and second conductor patterns 76A and 76B
are arranged to be line-symmetric when viewed from a plane face of
the input and output board 70.
[0100] Then, the first conductor pattern 76A includes a first
A-phase conductor pattern 76Aa connected with and extending from
the first A-phase output terminal 66Aa of the first power module
60A, a first B-phase conductor pattern 76Ab connected with and
extending from the first B-phase output terminal 66Ab of the first
power module 60A, and a first C-phase conductor pattern 76Ac
connected with and extending from the first C-phase output terminal
66Ac of the first power module 60A.
[0101] Here, the first A-phase conductor pattern 76Aa extends on a
top face of the input and output board 70 from the first A-phase
output terminal 66Aa to a first board connection portion 121ca of
the A phase terminal 121 of the three-phase output connector
100.
[0102] In addition, the first B-phase conductor pattern 76Ab
extends on the top face of the input and output board 70 from the
first B-phase output terminal 66Ab to a first board connection
portion 122ca of the B phase terminal 122 of the three-phase output
connector 100.
[0103] Further, the first C-phase conductor pattern 76Ac extends on
the top face 70d of the input and output board 70 from the first
C-phase output terminal 66Ac to the bottom face 70e of the input
and output board 70 through the first through hole 77a so as not to
interfere with the first B-phase conductor pattern 76Ab, extends to
the second through hole 77b on the bottom face 70e of the input and
output board 70, then extends to the top face 70d of the input and
output board 70 through the second through hole 77b, and further
extends on the top face 70d of the input and output board 70 to a
first board connection portion 123ca of the C phase terminal 123 of
the three-phase output connector 100.
[0104] In addition, the second conductor pattern 76B includes, a
second A-phase conductor pattern 76Ba connected with and extending
from the first A-phase output terminal 66Ba of the second power
module 60B, a second B-phase conductor pattern 76Bb connected with
and extending from the second B-phase output terminal 66Bb of the
second power module 60B, and a second C-phase conductor pattern
76Bc connected with and extending from the second C-phase output
terminal 66Bc of the second power module 60B.
[0105] Here, the second A-phase conductor pattern 76Ba extends on
the top face of the input and output board 70, from the second
A-phase output terminal 66Ba to a second board connection portion
121cb of the A phase terminal 121 of the three-phase output
connector 100.
[0106] In addition, the second B-phase conductor pattern 76Bb
extends on the top face of the input and output board 70 from the
second B-phase output terminal 66Bb to a second board connection
portion 122cb of the B phase terminal 122 of the three-phase output
connector 100.
[0107] Further, the second C-phase conductor pattern 76Bc extends
on the top face 70d of the input and output board 70 from the
second C-phase output terminal 66Bc to the bottom face 70e of the
input and output board 70 through the third through hole 77c so as
not to interfere with the second B-phase conductor pattern 76Bb,
extends to the fourth through hole 77d on the bottom face 70e of
the input and output board 70, then extends to the top face 70d of
the input and output board 70 through the fourth through hole 77d,
and further extends on the top face 70d of the input and output
board 70 to a second board connection portion 123cb of the C phase
terminal 123 of the three-phase output connector 100.
[0108] The three-phase output connector 100 electrically conducts
an A-phase motor drive current I1a, a B-phase motor drive current
I1b, and a C-phase motor drive current I1c, which are output
currents from the first power module 60A, with the motor windings
La, Lb, and Lc of the respective phases of the electric motor 12,
and also electrically conducts an A-phase motor drive current I2a,
a B-phase motor drive current I2b, and a C-phase motor drive
current I1c, which are output currents from the second power module
60B, with the motor windings La, Lb, and Lc of the respective
phases of the electric motor 12. Therefore, a connector (not
illustrated) connected with electric wires (not illustrated)
respectively connected with the motor windings La, Lb, and Lc of
the respective phases of the electric motor 12 is configured to be
mated with three-phase output connector 100.
[0109] The three-phase output connector 100, as illustrated in FIG.
10 to FIG. 12, and FIG. 16 to FIG. 18, includes an insulating
housing 110, and terminals 120 secured to the housing 110. The
terminals 120 includes an A-phase terminal 121, a B-phase terminal
122, and a C-phase terminal 123, respectively corresponding to the
A phase, B phase, and C phase of the electric motor 12. When the
housing 110 is molded, the A-phase terminal 121, the B-phase
terminal 122, and the C-phase terminal 123 are insert-molded to be
insulated from each other and overlap each other from bottom to top
in an order of the A-phase terminal 121, the C-phase terminal 123,
and the B-phase terminal 122 as illustrated in FIG. 11.
[0110] Here, as illustrated in FIG. 10, FIG. 12, FIG. 13A, FIG.
13B, and FIG. 13C, the A-phase terminal 121 includes an output
terminal portion 121a having a substantially rectangular shape
extending in the up-down direction to be connected to the electric
motor 12, a coupling portion 121b having a substantially
rectangular shape bending from an upper end of the output terminal
portion 121a and extending frontward and in a left direction, and
first and second board connection portions 121ca and 121cb
extending downwardly from front edges of both of left and right
ends of the coupling portion 121b (edges on an opposite side to the
edges from which the output terminal portion 121a extends). The
first and second board connection portions 121ca and 121cb of the
A-phase terminal 121 are arranged to be line-symmetric when viewed
from a plane face of the output connector 100. The A-phase terminal
121 is made by stamping and bending a conductive metal plate.
[0111] In addition, as illustrated in FIG. 10, FIG. 12, FIG. 14A,
FIG. 14B, and FIG. 14C, the B-phase terminal 122 includes an output
terminal portion 122a having a substantially rectangular shape
extending in the up-down direction to be connected to the electric
motor 12, a coupling portion 122b having a substantially
rectangular shape bending from an upper end of the output terminal
portion 122a and extending frontward, and first and second board
connection portions 122ca and 122cb extending downwardly from front
edges of both of left and right ends of the coupling portion 122b.
The B-phase terminal 122 is made by stamping and bending a
conductive metal plate. The first and second board connection
portions 122ca and 122cb are arranged to be line-symmetric when
viewed from a plane face of the output connector 100, and in
addition, are arranged on inner sides than the first and second
board connection portions 121ca and 121cb of the A-phase terminal
121, as illustrated in FIG. 17.
[0112] Further, as illustrated in FIG. 10, FIG. 12, FIG. 15A, FIG.
15B, and FIG. 15C, the C-phase terminal 123 includes an output
terminal portion 123a having a substantially rectangular shape
extending in the up-down direction to be connected to the electric
motor 12, a coupling portion 123b having a substantially
rectangular shape bending from an upper end of the output terminal
portion 123a and extending frontward and in a right direction, and
first and second board connection portions 123ca and 123cb
extending downwardly from front edges on both of left and right
sides of the coupling portion 123b (edges on an opposite side to
the edges from which the output terminal portion 123a extends). The
C-phase terminal 123 is made by stamping and forming a conductive
metal plate. The first and second board connection portions 123ca
and 123cb are arranged to be line-symmetric when viewed from a
plane face of the output connector 100, and in addition, arranged
on inner sides than the first and second board connection portions
121ca and 121cb of the A-phase terminal 121 and on outer sides than
the first and second board connection portions 122ca and 122cb of
the B-phase terminal 122, as illustrated in FIG. 17.
[0113] The first board connection portion 121ca of the A-phase
terminal 121, the first board connection portion 122ca of the
B-phase terminal 122, and the first board connection portion 123ca
of the C-phase terminal 123 are connected to the first conductor
pattern 76A of the input and output board 70. In addition, the
second board connection portion 121cb of the A-phase terminal 121,
the second board connection portion 122cb of the B-phase terminal
122, and the second board connection portion 123cb of the C-phase
terminal 123 are connected to the second conductor pattern 76B of
the input and output board 70.
[0114] To be specific, the first board connection portion 121ca of
the A-phase terminal 121 is connected by soldering with a first
A-phase conductor pattern 76Aa, the first board connection portion
122ca of the B-phase terminal 122 is connected by soldering with a
first B-phase conductor pattern 76Ab, and the first board
connection portion 123ca of the C-phase terminal 123 is connected
by soldering with the first C-phase conductor pattern 76Ac.
[0115] Also, the second board connection portion 121cb of the
A-phase terminal 121 is connected by soldering with the second
A-phase conductor pattern 76Ba, the second board connection portion
122cb of the B-phase terminal 122 is connected by soldering with
the second B-phase conductor pattern 76Bb, and the second board
connection portion 123cb of the C-phase terminal 123 is connected
by soldering with the second C-phase conductor pattern 76Bc.
[0116] In addition, the three-phase output connector 100 is
attached to the side wall 93a of the case 91 with a pair of left
and right attachment screw members 111, as illustrated in FIG.
4.
[0117] In the electronic control unit 50 having the above
configuration, the first and second conductor patterns 76A and 76B
are formed on the input and output board 70 to be connected with
the respective output terminals 66A and 66B of the first and second
power modules 60A and 60B, and then to extend independently of each
other. Accordingly, the motor drive currents output from the
respective output terminals 66A and 66B of the first and second
power modules 60A and 60B are flowed on the input and output board
70 through the first and second conductor patterns 76A and 76B in
two lines independently of each other. The terminals 120 (121, 122,
and 123) are mounted on the output connector 100. The terminals 120
include the output terminal portions 121a, 122a, and 123a to be
connected to the electric motor 12, and the first board connection
portions 121ca, 122ca, and 123ca and the second board connection
portions 121cb, 122cb, and 123cb, respectively extending from the
output terminal portions 121a, 122a, and 123a and connected to the
first and second conductor patterns 76A and 76B. Accordingly, the
motor drive currents flow through the first and second conductor
patterns 76A and 76B in two lines independently of each other, flow
through the first board connection portions 121ca, 122ca, and 123ca
and the second board connection portions 121cb, 122cb, and 123cb of
the terminals 120 (121, 122, and 123) independently of each other,
and join together at the output terminal portions 121a, 122a, and
123a to the electric motor 12, to be specific, at the coupling
portions 121b, 122b, and 123b. Accordingly, the motor driver
currents join together at the output terminal portions 121a, 122a,
and 123a that are closest to the electric motor 12, so that
distances from the output terminals 66A and 66B of the first and
second power modules 60A and 60B to the electric current joining
point can be made longer than the case where the electric currents
are joined together on the input and output board 70. This
configuration enables suppression of power loss from the two output
terminals 66A and 66B of the first and second power modules 60A and
60B to the electric current joining point. Since the power loss is
proportional to the square of the current value, a shorter distance
through which the heavy-current after the electric currents are
joined together flows through may be desirable.
[0118] Specifically, the motor drive current output from the first
A-phase output terminal 66Aa of the first power module 60A flows
through the first A-phase conductor pattern 76Aa, and the motor
drive current output from the second A-phase output terminal 66Ba
of the second power module 60B flows through the second A-phase
conductor pattern 76Ba. Then, the motor drive current that has
flowed through the first A-phase conductor pattern 76Aa and the
motor drive current that has flowed through the second A-phase
conductor pattern 76Ba respectively flow across the first board
connection portion 121ca and the second board connection portion
121cb of the A-phase terminal 121 independently of each other, and
join together at the coupling portion 121b.
[0119] Further, the motor drive current output from the first
B-phase output terminal 66Ab of the first power module 60A flows
through the first B-phase conductor pattern 76Ab, and the motor
drive current output from the second B-phase output terminal 66Bb
of the second power module 60B flows through the second B-phase
conductor pattern 76Bb. Then, the motor drive current that has
flowed through the first B-phase conductor pattern 76Ab and the
motor drive current that has flowed through the second B-phase
conductor pattern 76Bb respectively flow across the first board
connection portion 122ca and the second board connection portion
122cb of the B-phase terminal 122 independently of each other, and
join together at the coupling portion 122b.
[0120] Furthermore, the motor drive current output from the first
C-phase output terminal 66Ac of the first power module 60A flows
through the first C-phase conductor pattern 76Ac, and the motor
drive current output from the second C-phase output terminal 66Bc
of the second power module 60B flows through the second C-phase
conductor pattern 76Bc. Then, the motor drive current that has
flowed through the first C-phase conductor pattern 76Ac and the
motor drive current that has flowed through the second C-phase
conductor pattern 76Bc respectively flow across the first board
connection portion 123ca and the second board connection portion
123cb of the C-phase terminal 123 independently of each other, and
join together at the coupling portion 123b.
[0121] Thus, the respective distances from output terminals 66A and
66B of the first and second power modules 60A and 60B to the
joining point of the electric currents can be made longer than the
case where the electric currents are joined together on the input
and output board 70. This configuration enables the suppression of
the power loss from the two output terminals 66A and 66B of the
first and second power modules 60A and 60B to the joining point of
the electric currents.
[0122] In addition, since the first board connection portion 121ca
of the A-phase terminal 121 is connected by soldering with the
first A-phase conductor pattern 76Aa and the second board
connection portion 121cb of the A-phase terminal 121 is connected
by soldering with the second A-phase conductor pattern 76Ba, even
if one of the board connection portions is incompletely connected,
the A-phase motor drive current flows, as long as the other one of
the board connection portions is connected properly. Further, this
phenomenon also applies to the B-phase terminal 122 and the C-phase
terminal 123. Accordingly, advantages of a redundant electric join
between the electronic control unit 50 and the electric motor 12 is
also obtainable.
[0123] In addition, the first and second conductor patterns 76A and
76B are arranged to be line-symmetric when viewed from a plane face
of the input and output board 70. This configuration allows a
simple configuration of the input and output board 70.
[0124] Further, the first conductor pattern 76A includes the first
A-phase conductor pattern 76Aa connected with and extending from
the first A-phase output terminal 66Aa of the first power module
60A, the first B-phase conductor pattern 76Ab connected with and
extending from the first B-phase output terminal 66Ab of the first
power module 60A, and the first C-phase conductor pattern 76Ac
connected with and extending from the first C-phase output terminal
66Ac of the first power module 60A. Also, the second conductor
pattern 76B includes the second A-phase conductor pattern 76Ba
connected with and extending from the second A-phase output
terminal 66Ba of the second power module 60B, the second B-phase
conductor pattern 76Bb connected with and extending from the second
B-phase output terminal 66Bb of the second power module 60B, and
the second C-phase conductor pattern 76Bc connected with and
extending from the second C-phase output terminal 66Bc of the
second power module 60B. Accordingly, this configuration enables
the wiring of the conductor patterns corresponding to the
three-phase electric motor 12 of A phase, B phase, and C phase.
[0125] Further, the terminal 120 includes the A-phase terminal 121,
the B-phase terminal 122, and the C-phase terminal 123,
respectively corresponding to the A phase, B phase, and C phase of
the electric motor 12. The A-phase terminal 121 includes the output
terminal portion 121a, the first board connection portion 121ca to
be connected to the first A-phase conductor pattern 76Aa, and the
second board connection portion 121cb to be connected to the second
A-phase conductor pattern 76Ba. The B-phase terminal 122 includes
the output terminal portion 122a, the first board connection
portion 122ca to be connected to the first B-phase conductor
pattern 76Ab, and the second board connection portion 122cb to be
connected to the second B-phase conductor pattern 76Bb.
Furthermore, the C-phase terminal 123 includes the output terminal
portion 123a, the first board connection portion 123ca to be
connected to the first C-phase conductor pattern 76Ac, and the
second board connection portion 123cb to be connected to the second
C-phase conductor pattern 76Bc. Therefore, a terminal configuration
corresponding to the three-phase electric motor 12 of the A phase,
B phase, and C phase is achievable.
[0126] Moreover, the first and second board connection portions
121ca and 121cb of the A-phase terminal 121, the first and second
board connection portions 122ca and 122cb of the B-phase terminal
122, and the first and second board connection portions 123ca and
123cb of the C-phase terminal 123 are arranged to be line-symmetric
when viewed from a plane face of the output connector 100. This
configuration easily achieves the arrangements of the first and
second conductor patterns 76A and 76B to be line-symmetric when
viewed from a plane face of the input and output board 70.
[0127] The embodiments of the present invention have been described
heretofore, but, the present invention is not limited to the above
embodiments. Various changes and improvements are applicable.
[0128] For example, the first and second conductor patterns 76A and
76B formed in the input and output board 70 may be configured such
that the motor drive currents are flowed independently of each
other, and are not limited to those illustrated in FIG. 17.
[0129] Also, an insert molding board that eliminates the need for
through-holes may be applicable to the input and output board
70.
[0130] In addition, the arrangements and shapes of the A-phase
terminal 121, the B-phase terminal 122, and the C-phase terminal
123 included in the terminal 120 can be configured such that each
of the A-phase terminal 121, the B-phase terminal 122, and the
C-phase terminal 123 is insulated from each other, and the output
terminal portion to be connected to the electric motor 12 and the
first and second board connection portions respectively connected
with the first and second conductor patterns 76A and 76B extending
from the output terminal portion are provided. The arrangements and
shapes are not limited to those illustrated in FIG. 10 to FIG.
18.
[0131] Further, in each of the A-phase terminal 121, the B-phase
terminal 122, and the C-phase terminal 123, the first and second
board connection portions 121ca, 121cb, 122ca, 122cb, 123ca, and
123cb may directly extend from the output terminal portions 121a,
122a, and 123a, without extending from the coupling portions 121b,
122b, and 123b.
[0132] Furthermore, the terminal 120 does not necessarily include
the A-phase terminal 121, the B-phase terminal 122, or the C-phase
terminal 123, and may be a single terminal.
[0133] In addition, in the above-described electronic control unit,
the first and second conductor patterns may be arranged to be
line-symmetric when the first and second conductor patterns are
viewed from a plane of the input and output board.
[0134] Further, in the above-described electronic control unit, a
first output terminal of the first power module may include a first
A-phase output terminal, a first B-phase output terminal, and a
first C-phase output terminal respectively corresponding to an A
phase, a B phase, and a C phase of the electric motor, a second
output terminal of the second power module may include a second
A-phase output terminal, a second B-phase output terminal, and a
second C-phase output terminal respectively corresponding to the A
phase, the B phase, and the C phase of the electric motor, the
first conductor pattern may include a first A-phase conductor
pattern connected with and extending from the first A-phase output
terminal of the first power module, a first B-phase conductor
pattern connected with and extending from the first B-phase output
terminal of the first power module, and a first C-phase conductor
pattern connected with and extending from the first C-phase output
terminal of the first power module, and the second conductor
pattern may include a second A-phase conductor pattern connected
with and extending from the second A-phase output terminal of the
first power module, a second B-phase conductor pattern connected
with and extending from the second B-phase output terminal of the
first power module, and a second C-phase conductor pattern
connected with and extending from the second C-phase output
terminal of the first power module.
[0135] Further, in the above-described electronic control unit, the
terminal may include an A-phase terminal, a B-phase terminal, and a
C-phase terminal respectively corresponding to the A phase, the B
phase, and the C phase of the electric motor, the A-phase terminal
may include the output terminal portion, the first board connection
portion to be connected to the first A-phase conductor pattern, and
the second board connection portion to be connected to the second
A-phase conductor pattern, the B-phase terminal may include the
output terminal portion, the first board connection portion to be
connected to the first B-phase conductor pattern, and the second
board connection portion to be connected to the second B-phase
conductor pattern, and the C-phase terminal may include the output
terminal portion, the first board connection portion to be
connected to the first C-phase conductor pattern, and the second
board connection portion to be connected to the second C-phase
conductor pattern.
[0136] Furthermore, in the above-described electronic control unit,
the A-phase terminal, the B-phase terminal, and the C-phase
terminal may be insert-molded to be insulated from each other and
overlap each other, when a housing is formed.
[0137] Moreover, in the above-described electronic control unit,
the first and second board connection portions of the A-phase
terminal, the first and second board connection portions of the
B-phase terminal, and the first and second board connection
portions of the C-phase terminal may be arranged to be
line-symmetric when viewed from a plane of the output
connector.
[0138] In addition, according to another aspect of the present
invention, there is provided an electric power steering device
including any one of the above-described electronic control
units.
[0139] Further, according to yet another aspect of the present
invention, there is provided a vehicle including the
above-described electric power steering device.
[0140] Furthermore, according to further another aspect of the
present invention, there is provided an electronic control unit
including: a power module including switching elements; an input
and output board on which an input connector and an output
connector to be connected to an electric motor are mounted; and a
control board on which a controller configured to control output
currents from the power module. The power module includes a seal
body including the switching elements and having a rectangular
plane, a plurality of first leads arranged along one of two sides
located on opposite sides of the seal body, and a plurality of
second leads arranged along the other one of the two sides of the
seal body. The input and output board and the control board
respectively have planes arranged to face each other at a given
interval, the plurality of first leads are connected to the input
and output board, the plurality of second leads are connected to
the control board, the plurality of first leads include a power
supply input lead to which the power is supplied from the input
connector, and the plurality of second leads include a power supply
output lead electrically connected with the power supply input lead
in the seal body.
[0141] In addition, in the above-described electronic control unit,
the plurality of first leads may include first and second power
supply input leads electrically separated from each other,
operating as a power supply input leads. The plurality of second
leads may include first and second power supply output leads
electrically separated from each other, operating as a power supply
output leads. The first power supply input lead may be electrically
connected with the first power supply output lead, the second power
supply input lead may be electrically connected with the second
power supply output lead, a first reference potential may be
supplied to the first power supply input lead, and a second
reference potential, which is different from the first reference
potential, may be supplied to the second power supply input
lead.
[0142] Further, in the above-described electronic control unit, the
first and second power supply input leads may be electrically
connected with the switching element. Moreover, in the
above-described electronic control unit, the first and second power
supply output leads may be electrically connected with the control
device.
REFERENCE SIGNS LIST
[0143] 1 . . . steering wheel, 2 . . . steering shaft, 2a . . .
input shaft, 2b . . . output shaft, 3 . . . steering torque sensor,
4 . . . universal joint, 5 . . . lower shaft, 6 . . . universal
joint portion, 7 . . . pinion shaft, 8 . . . steering gear, 8a . .
. pinion, 8b . . . rack, 9 . . . tie rod, 10 . . . steering
assistance mechanism, 11 . . . reduction gear, 12 . . . electric
motor, 12a . . . output shaft, 12b . . . first flange portion, 12c
. . . second flange portion, 13 . . . motor rotational angle
detection circuit, 13a . . . rotational position sensor, La . . .
A-phase motor winding, Lb . . . B-phase motor winding, Lc . . .
C-phase motor winding, 20 . . . motor controller, 21 . . . speed
sensor, 22 . . . battery, 31 . . . control operation device, 32A .
. . first motor drive circuit, 32B . . . second motor drive
circuit, 33A . . . first motor current cutoff circuit, 33B . . .
second motor current cutoff circuit, 39A, 39B . . . current
detection circuit, 41A, 41B . . . gate drive circuit, 42A, 42B . .
. inverter circuit, 43 . . . noise filter, 44A, 44B . . . power
cutoff circuit, 50 . . . electronic control unit, 60A . . . first
power module, 60B . . . second power module, 61 . . . seal body,
61a, 61b . . . long side, 61c, 61d . . . short side, 63 . . . first
lead, 63a . . . first part, 63b . . . second part, 63c . . . third
part, 64 . . . second lead, 64a . . . first part, 64b . . . second
part, 65 . . . screw member, 66A . . . output terminal of the first
power module, 66Aa . . . first A-phase output terminal, 66Ab . . .
first B-phase output terminal, 66Ac . . . first C-phase output
terminal, 66B . . . output terminal of the second power module,
66Ba . . . second A-phase output terminal, 66Bb . . . second
B-phase output terminal, 66Bc . . . second C-phase output terminal,
70 . . . input and output board, 70c . . . screw through hole, 70d
. . . top face of the input and output board, 70e . . . bottom face
of the input and output board, 71 . . . power supply input
connector (input connector), 73 . . . electronic part (discrete
part), 73a . . . coil, 73b . . . coil, 75 . . . screw member, 76A .
. . first conductor pattern, 76Aa . . . first A-phase conductor
pattern, 76Ab . . . first B-phase conductor pattern, 76Ac . . .
first C-phase conductor pattern, 76B . . . second conductor
pattern, 76Ba . . . second A-phase conductor pattern, 76Bb . . .
second B-phase conductor pattern, 76Bc . . . second C-phase
conductor pattern, 77a . . . first through hole, 77b . . . second
through hole, 77c . . . third through hole, 77d . . . fourth
through hole, 80 . . . control board, 80a . . . screw through
holes, 80b . . . top face of the control board, 80c . . . bottom
face of the control board, 81 . . . signal input connector, 82A . .
. gate drive device, 82B . . . gate drive device, 83 . . . opening,
85 . . . screw member, 90 . . . housing, 91 . . . case, 92 . . .
ceiling, 93a, 93b, 93c, 93d . . . side wall, 95 . . . cover, 95a .
. . screw through hole, 95b . . . boss portion, 96 . . . screw
member, 100 . . . three-phase output connector (output connector),
110 . . . housing, 120 . . . terminal, 121 . . . A-phase terminal,
121a . . . output terminal portion, 121b . . . coupling portion,
121ca . . . first board connection portion, 121cb . . . second
board connection portion, 122 . . . B-phase terminal, 122a . . .
output terminal portion, 122b . . . coupling portion, 122ca . . .
first board connection portion, 122cb . . . second board connection
portion, 123 . . . C-phase terminal, 123a . . . output terminal
portion, 123b . . . coupling portion, 123ca . . . first board
connection portion, 123cb . . . second board connection portion
* * * * *