U.S. patent application number 13/786472 was filed with the patent office on 2013-07-18 for fault tolerant modular battery management system.
The applicant listed for this patent is Hak Hon CHAU. Invention is credited to Hak Hon CHAU.
Application Number | 20130181680 13/786472 |
Document ID | / |
Family ID | 43305865 |
Filed Date | 2013-07-18 |
United States Patent
Application |
20130181680 |
Kind Code |
A1 |
CHAU; Hak Hon |
July 18, 2013 |
FAULT TOLERANT MODULAR BATTERY MANAGEMENT SYSTEM
Abstract
A modular battery management system for managing a plurality of
batteries and driving a load includes a plurality of battery
management control modules; a plurality of bi-directional voltage
converter modules respectively connected to the batteries and
connected to the battery management control modules, the
bi-directional voltage converter modules being connected to each
other in parallel; and a plurality of energy storage modules
respectively connected with the bi-directional voltage converter
modules in parallel and connected to the load. The bi-directional
voltage converter modules are configured to transfer electric
energy from the batteries to the load or from the energy storage
modules to the batteries. The batteries, the bi-directional voltage
converter modules, the energy storage modules, and the battery
management control modules are arranged in a redundant topology so
that if any one of the components fails, the other components
resume the functions of the failing component.
Inventors: |
CHAU; Hak Hon; (Hong Kong,
HK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CHAU; Hak Hon |
Hong Kong |
|
HK |
|
|
Family ID: |
43305865 |
Appl. No.: |
13/786472 |
Filed: |
March 6, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12722542 |
Mar 12, 2010 |
8410755 |
|
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13786472 |
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61187273 |
Jun 15, 2009 |
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Current U.S.
Class: |
320/134 |
Current CPC
Class: |
B60L 2210/12 20130101;
B60L 58/10 20190201; B60L 3/04 20130101; Y02T 10/7072 20130101;
B60L 58/21 20190201; B60L 11/1851 20130101; B60L 58/12 20190201;
B60L 58/22 20190201; Y02T 10/70 20130101; B60L 3/0046 20130101;
Y02T 90/14 20130101; B60L 58/16 20190201; B60L 2210/14 20130101;
B60L 58/18 20190201; B60L 50/64 20190201; Y02T 90/12 20130101; Y02T
10/72 20130101 |
Class at
Publication: |
320/134 |
International
Class: |
B60L 11/18 20060101
B60L011/18 |
Claims
1. A modular battery management system for managing a plurality of
batteries and driving a load, the system comprising: a plurality of
battery management control modules; a plurality of bi-directional
voltage converter modules respectively connected to the batteries
and connected to the battery management control modules, the
bi-directional voltage converter modules being connected to each
other in parallel; and a plurality of energy storage modules
respectively connected with the bi-directional voltage converter
modules in parallel and connected to the load; wherein: the
bi-directional voltage converter modules are configured to transfer
electric energy from the batteries to the load or from the energy
storage modules to the batteries; and the battery management
control modules are configured to execute a predetermined program
based on the state information of each battery and control the
bi-directional voltage converter modules.
2. The modular battery management system of claim 1, wherein the
energy storage modules are capacitors, super capacitors, ultra
capacitors, flywheels or any form of recyclable electric energy
storage elements.
3. The modular battery management system of claim 1, wherein the
bi-directional voltage converter modules are configured to transfer
electric energy from the energy storage modules to the batteries so
as to charge the batteries when the voltage on the energy storage
modules exceeds a predetermined value.
4. The modular battery management system of claim 1, wherein the
bi-directional voltage converter modules are respectively connected
to the batteries through a first plurality of switches, the energy
storage modules are respectively connected with the bi-directional
voltage converter modules in parallel through a second plurality of
switches, the load is connected to the energy storage modules
through a third switch, and the first plurality of switches, the
second plurality of switches and the third switch are controlled by
the battery management control modules.
5. The modular battery management system of claim 1 further
comprising a plurality of battery state monitoring modules
respectively connected to the batteries, connected to the battery
management control modules, and configured for monitoring the state
of each battery and sending the state information of each battery
to the battery management control modules, wherein the battery
state monitoring modules and the bi-directional voltage converter
modules are connected to the battery management control modules
through a control bus.
6. The modular battery management system of claim 5, wherein when
one battery management control module stops working properly, the
other battery management control modules are configured to resume
the functions of the battery management control module.
7. The modular battery management system of claim 1, wherein the
battery management control modules are configured to adjust the
output voltage levels of the bi-directional voltage converter
modules based on an instruction from a user.
8. The modular battery management system of claim 4, wherein the
battery management control modules are configured to disable one of
the first plurality of switches and the bi-directional voltage
converter module connected with the switch simultaneously.
9. A modular battery management system for managing a plurality of
batteries and driving a load, the system comprising: a plurality of
battery management control modules; a plurality of bi-directional
voltage converter modules respectively connected to the batteries
through a first plurality of switches and connected to the battery
management control modules, the bi-directional voltage converter
modules being connected to each other in parallel; and a plurality
of energy storage modules respectively connected with the
bi-directional voltage converter modules in parallel and connected
to the load; wherein: the bi-directional voltage converter modules
are configured to transfer electric energy from the batteries to
the load or from the energy storage modules to the batteries; and
the battery management control modules are configured to execute a
predetermined program based on the state information of each
battery and control the bi-directional voltage converter modules
and the first plurality of switches.
10. The modular battery management system of claim 9, wherein the
energy storage modules are capacitors, super capacitors, ultra
capacitors, flywheels, or any form of recyclable electric energy
storage elements.
11. The modular battery management system of claim 9, wherein the
bi-directional voltage converter modules are configured to transfer
electric energy from the energy storage modules to the batteries so
as to charge the batteries when the voltage on the energy storage
modules exceeds a predetermined value.
12. The modular battery management system of claim 9, wherein the
battery management control modules are configured to disable one of
the first plurality of switches and the bi-directional voltage
converter module connected with the switch simultaneously.
13. The modular battery management system of claim 9 further
comprising a plurality of battery state monitoring modules
respectively connected to the batteries, connected to the battery
management control modules, and configured for monitoring the state
of each battery and sending the state information of each battery
to the battery management control modules, wherein the battery
state monitoring modules and the bi-directional voltage converter
modules are connected to the battery management control modules
through a control bus.
14. The modular battery management system of claim 13, wherein when
one battery management control module stops working properly, the
other battery management control modules are configured to resume
the functions of the battery management control module.
15. The modular battery management system of claim 9, wherein the
battery management control modules are configured to adjust the
output voltage levels of the bi-directional voltage converter
modules based on an instruction from a user.
16. A modular battery management system for managing a plurality of
batteries and driving a load, the system comprising: a plurality of
battery management control modules; a plurality of battery state
monitoring modules respectively connected to the batteries,
connected to the battery management control modules, and configured
for monitoring the state of each battery and sending the state
information of each battery to the battery management control
modules; a plurality of bi-directional voltage converter modules
respectively connected to the batteries through a first plurality
of switches and connected to the battery management control
modules, the bi-directional voltage converter modules being
connected to each other in parallel; and a plurality of energy
storage modules respectively connected with the bi-directional
voltage converter modules in parallel through a second plurality of
switches and connected to the load through a third switch; wherein:
the bi-directional voltage converter modules are configured to
transfer electric energy from the batteries to the load or from the
energy storage modules to the batteries; the battery management
control modules are configured to execute a predetermined program
based on the state information of each battery and control the
bi-directional voltage converter modules, the first plurality of
switches, the second plurality of switches and the third switch;
and the battery state monitoring modules and the bi-directional
voltage converter modules are connected to the battery management
control modules through a control bus.
17. The modular battery management system of claim 16, wherein the
bi-directional voltage converter modules are configured to transfer
electric energy from the energy storage modules to the batteries so
as to charge the batteries when the voltage on the energy storage
modules exceeds a predetermined value.
18. The modular battery management system of claim 16, wherein the
battery management control modules are configured to disable one of
the first plurality of switches and the bi-directional voltage
converter module connected with the switch simultaneously.
19. The modular battery management system of claim 16, wherein the
battery management control modules are configured to adjust the
output voltage levels of the bi-directional voltage converter
modules based on an instruction from a user.
20. The modular battery management system of claim 16, wherein the
energy storage modules are capacitors, super capacitors, ultra
capacitors, flywheels, or any form of recyclable electric energy
storage elements.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This present application is a Continuation Application of
prior application Ser. No. 12/722,542, filed on Mar. 12, 2010,
which claims the benefit of U.S. provisional Patent Application No.
61/187,273, filed on Jun. 15, 2009; the contents of which are
hereby incorporated by reference.
FIELD OF THE PATENT APPLICATION
[0002] The present application generally relates to battery
management systems for electric vehicles or hybrid electric
vehicles and more particularly to a fault tolerant modular battery
management system (MBMS) capable of supporting critical loads with
high power requirements.
BACKGROUND
[0003] The electrical power requirements for electric vehicles (EV)
or hybrid electric vehicles (HEV) can be very high. The battery
will undergo discharging and charging cycles during vehicle start
up/running mode and running/braking/internal and external charging
mode respectively. The management of battery state of health,
battery state of charge and battery temperature is critical in
electric vehicle or hybrid electric vehicle applications when
electric power cannot be interrupted during driving. And, different
battery types, voltage and power requirements in different electric
vehicles or hybrid electric vehicles may require different battery
management systems. Therefore, the battery power supply system
framework may be totally different from one vehicle design to
another vehicle design due to the differences in battery type,
power requirement and vehicle operating voltage. Sometimes the
charging and replacement time of the battery packs may create a
temporary interruption to user. A failed battery pack may cause the
electric vehicle or hybrid electric vehicle to malfunction
instantly.
[0004] Conventionally, the battery packs (or cells) are connected
in series forming a Battery Pack Assembly (BPA) in order to provide
high voltage and high current to the electric vehicle or hybrid
electric vehicle motors and other auxiliary systems. Since the
battery packs or cells are connected in series, the charging and
discharging current will flow through each battery pack (or cell)
simultaneously. This causes problems in balancing individual
battery pack (or cell) characteristics. A conventional battery
management system detects the individual battery pack's (cell's)
state of charge, state of health and battery temperature through
complicated battery management design because of the serial
connections between batteries. Individual battery pack (or cell),
depending on the detected battery pack (or cell) condition, will be
switched to be connected with (ON) or disconnected from (OFF) the
serial connected battery packs (or cells). As a result, the BPA
output voltage fluctuates. This will cause instability problem to
motor drivers and associated circuits. Therefore, a DC/DC converter
will be employed to convert the fluctuating BPA output voltage to a
stable voltage supply for motor drivers and associated circuits.
However, the DC/DC converter must operate at high voltage and high
current conditions. The high power dissipation in the DC/DC
converter generally lowers the reliability of the overall system.
The system will shut down whenever the DC/DC converter fails.
Further, the battery pack assembly (BPA) power cannot be easily
increased or decreased to match with different loading
requirements. Furthermore, a dead battery pack or cell cannot be
replaced until the battery pack assembly (BPA) is disassembled from
the vehicle.
[0005] Accordingly, there is a need in the art for an improved
battery management system with fault tolerant features to resolve
the battery imbalance and dead cell problems. Further, additional
features such as variation of power bus voltage, power output
capacity and number of batteries are desired to be achieved.
[0006] The above description of the background is provided to aid
in understanding a fault tolerant modular battery management
system, but is not admitted to describe or constitute pertinent
prior art to the fault tolerant modular battery management system
disclosed in the present application.
SUMMARY
[0007] The present patent application is directed to a modular
battery management system for managing a plurality of batteries and
driving a load. In one aspect, the system includes a plurality of
battery management control modules; a plurality of bi-directional
voltage converter modules respectively connected to the batteries
and connected to the battery management control modules, the
bi-directional voltage converter modules being connected to each
other in parallel; and a plurality of energy storage modules
respectively connected with the bi-directional voltage converter
modules in parallel and connected to the load. The bi-directional
voltage converter modules are configured to transfer electric
energy from the batteries to the load or from the energy storage
modules to the batteries. The battery management control modules
are configured to execute a predetermined program based on the
state information of each battery and control the bi-directional
voltage converter modules.
[0008] The energy storage modules may be capacitors, super
capacitors, ultra capacitors, flywheels or any form of recyclable
electric energy storage elements.
[0009] The bi-directional voltage converter modules may be
configured to transfer electric energy from the energy storage
modules to the batteries so as to charge the batteries when the
voltage on the energy storage modules exceeds a predetermined
value.
[0010] The bi-directional voltage converter modules may be
respectively connected to the batteries through a first plurality
of switches. The energy storage modules are respectively connected
with the bi-directional voltage converter modules in parallel
through a second plurality of switches. The load is connected to
the energy storage modules through a third switch. The first
plurality of switches, the second plurality of switches and the
third switch are controlled by the battery management control
modules.
[0011] The battery management control modules may be configured to
disable one of the first plurality of switches and the
bi-directional voltage converter module connected with the switch
simultaneously.
[0012] The modular battery management system may further include a
plurality of battery state monitoring modules respectively
connected to the batteries, connected to the battery management
control modules, and configured for monitoring the state of each
battery and sending the state information of each battery to the
battery management control modules. The battery state monitoring
modules and the bi-directional voltage converter modules are
connected to the battery management control modules through a
control bus.
[0013] When one battery management control module stops working
properly, the other battery management control modules may be
configured to resume the functions of the battery management
control module.
[0014] The battery management control modules may be configured to
adjust the output voltage levels of the bi-directional voltage
converter modules based on an instruction from a user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic system block diagram of a fault
tolerant modular battery management system according to an
embodiment of the present patent application.
[0016] FIG. 2 is a schematic circuit diagram of the fault tolerant
modular battery management system depicted in FIG. 1.
DETAILED DESCRIPTION
[0017] Reference will now be made in detail to a preferred
embodiment of the fault tolerant modular battery management system
disclosed in the present patent application, examples of which are
also provided in the following description. Exemplary embodiments
of the fault tolerant modular battery management system disclosed
in the present patent application are described in detail, although
it will be apparent to those skilled in the relevant art that some
features that are not particularly important to an understanding of
the fault tolerant modular battery management system may not be
shown for the sake of clarity.
[0018] Furthermore, it should be understood that the fault tolerant
modular battery management system disclosed in the present patent
application is not limited to the precise embodiments described
below and that various changes and modifications thereof may be
effected by one skilled in the art without departing from the
spirit or scope of the protection. For example, elements and/or
features of different illustrative embodiments may be combined with
each other and/or substituted for each other within the scope of
this disclosure.
[0019] FIG. 1 is a schematic system block diagram of a fault
tolerant modular battery management system according to an
embodiment of the present patent application. FIG. 2 is a schematic
circuit diagram of the fault tolerant modular battery management
system depicted in FIG. 1. Referring to FIG. 1 and FIG. 2, the
fault tolerant modular battery management system includes a
plurality of battery state monitoring modules (201, 202, . . . ,
20n), a plurality of bi-directional DC/DC converter modules (401,
402, . . . , 40n), a plurality of energy storage modules (1401,
1402, . . . , 140n), a plurality of battery management control
modules (1201, . . . , 120n) and a plurality of battery packs (or
cells) (101, 102, . . . , 10n). Each battery pack (or cell), such
as 101, 102, . . . , 10n, is individually connected to a dedicated
battery state monitoring module and then linked to a bi-directional
DC/DC converter (such as 401, 402, . . . , 40n) through a plurality
of switches 301, 302, . . . , 30n. This combination is called
Battery Power Conversion Module (BPCM). Each battery pack (or cell)
is isolated from other battery packs (or cells). This topology is
different from serially connected batteries in conventional battery
management systems. The bi-directional DC/DC converter outputs are
connected in parallel so as to increase the overall output current
capacity to provide loading current.
[0020] The battery packs may include all kinds of batteries, which
may be but not limited to lead-acid batteries, Nickel-metal hydride
batteries, Nickel-Cadmium batteries, Lithium-Ion batteries,
Lithium-Polymer batteries, Zebra Na/NiCl.sub.2 batteries, NiZn
batteries, Lithium iron phosphate batteries, Ferrous batteries, or
any forms of electrical rechargeable energy storage elements.
[0021] As used herein, the energy storage (ES) modules refer to
electric energy storage elements, which may be but not limited to
capacitors, super capacitors, ultra capacitors, flywheels, or any
form of recyclable electric energy storage elements. In this
embodiment, referring to FIG. 1, the energy storage modules are the
capacitors 1401, . . . , 140n, which are connected to all the
bi-directional DC/DC converter modules through the switches 501, .
. . , 50n respectively.
[0022] As used herein, the bi-directional DC/DC converter modules
refer to electrical constructions that can act to charge energy
from Energy Storage (ES) module to battery packs (or cells) or
convert energy from battery packs (or cells) to Energy Storage (ES)
modules and a load connected with the energy storage modules.
[0023] The connections between the bi-directional DC/DC converter
outputs, energy storage modules and the load are called the power
buses. Electric current may be drawn from the power bus to the
load. The loading current will be shared among bi-directional DC/DC
converter outputs. The bi-directional DC/DC converter modules can
be of an isolated type or a non-isolated type, and are configured
to convert battery voltages to required loading voltage levels.
Therefore, the loading voltage is determined by the bi-directional
DC/DC converter output voltage settings instead of the serially
connected batteries' end terminal voltages in conventional battery
management systems. On the other hand, the bi-directional DC/DC
converter modules can charge the batteries when sufficient energy
is stored in the energy storage modules. This can resolve the
battery pack (or cell) imbalance problem in conventional battery
management systems.
[0024] The battery state monitoring (BSM) modules (201, 202, . . .
, 20n) are configured to provide battery state information to the
bi-directional DC/DC converter modules and Battery Management
Control (BMC) Modules (1201, . . . , 120n). The BMC modules are
configured to send control instructions to each Battery Power
Conversion Module (BPCM) per individual operating state. For
example, battery energy may be transferred from the batteries to
the power bus through the bi-directional DC/DC converter modules,
the batteries may receive energy from the power bus to charge the
batteries through the bi-directional DC/DC converter modules,
battery packs may be disabled and disconnected from the system,
batteries may be removed from the system and additional Battery
Power Conversion Modules (BPCMs) may be added to the system.
Simultaneously, some battery packs (or cells) may undergo discharge
cycles (delivering power), some other batteries may undergo
charging cycles (receiving power) and yet some other batteries may
be disconnected from the system, depending on the algorithm
executed in the BMC program.
[0025] The battery packs (cells) may be disconnected either under a
fully charged, an unsafe or a dead condition. If one of the
batteries is required to be removed from the system, the battery
state monitoring (BSM) module will activate a release signal on the
BSM module panel and to the BMC module. The fully charged battery
packs (cells) will be connected back to the BPCM under the control
of BMC module. The unsafe battery packs (or cells) are connected
back to BPCM under the control of BMC module if the unsafe
condition is removed.
[0026] A user can remove a battery from the modular battery
management system. Likewise, the user can install a replacement
battery to the modular battery management system and then activate
the battery state monitoring module to inform the Battery
Management Control (BMC) modules through the Battery Management
System (BMS) Control Bus. If a new battery is installed to the
system, additional BSMs and Bi-directional DC/DC converter are
required. The new or replacement battery will become a part of the
Modular Battery Management System (MBMS). With this technology, the
user can increase the Modular Battery Management System (MBMS)
output power by adding more Battery Power Conversion Modules
(BPCMs) without major system design change, or remove battery packs
(cells) from the system if required.
[0027] The power density of the batteries (or cells) may increase
the MBMS output power as well. The energy storage modules are
connected in parallel to the power bus. The energy storage modules
are energy storage devices that can be charged up with high energy
within a short period of time (for example, 10 to 20 minutes). The
energy storage modules serve as buffers for surge loading current
and in-rush charging current. When the voltage on energy storage
modules exceeds a preset value, the Battery Management Control
(BMC) modules will instruct the bi-directional DC/DC converter
modules to charge up the battery packs (or cells) through the BMS
control bus. During charging, the ES modules can be programmed to
charge the battery packs individually or all at once or
randomly.
[0028] The Battery Management Control (BMC) Modules are
programmable units that can be programmed to perform different
algorithms to meet different vehicle/car requirements, for example,
different voltage levels, different battery packs (or cells)
characteristics, and different loading current requirements.
Individual BMC module is configured to monitor the BMS control bus.
Once a BMC module is in fault condition, the other BMC modules will
take over the control without shutting down the system.
[0029] In addition to fault redundant features, the Battery
Management Control module can adjust the output voltage level of
the bi-directional DC/DC converter modules within certain range in
order to increase the torque of the motor (DC or AC) while
additional torque is required for hill climbing. Thus, it can serve
as an Electric Torque Control (ETC).
[0030] Referring to FIG. 1 and FIG. 2, the modular battery
management system is based on a redundant topology. Therefore, the
detailed description on the first stage of Battery Power Conversion
Module (BPCM) is explained here and it can be expanded to cover the
system up to n stages where n is a positive integer.
[0031] The first Battery Power Conversion Module (BPCM) stage
structure includes a battery 101, which has positive (+) terminal,
a negative (-) terminal and a battery temperature signal 1101. The
battery 101 is connected to a BSM module 201. The BSM 201 is an
electrical circuit that monitors the battery conditions, for
example the state of charge, the state of health, the battery
temperature, and the charging condition/status, and feedbacks the
information to a Battery Management System (BMS) control bus 1
through a signal path 601. The control signal 801, from the BSM
control bus 1, will be used to display the battery operating status
via status indication devices such as LEDs, a display panel or
lamps, which may be charging, discharging, dead battery, being
connected to the bi-directional DC/DC converter or disconnected
from the bi-directional DC/DC converter). The output voltage of the
battery 101 is connected to the switch 301. The switch 301 is an
electrical activated switch, which is used to control the
electrical connection between the BSM module 201 to the
bi-directional DC/DC converter 401. The switch 301 is electrically
controlled by a control signal 901, which is transmitted from the
Battery Management Control (BMC) modules 1201, . . . , 120n. The
switch 301 can be manually disabled during maintenance or
servicing. This is to avoid electrical hazard during maintenance or
servicing. In addition, the signal 901 controls the ON or OFF
status of the bi-directional DC/DC converter 401. If the switch 301
is disabled by the signal 901 or by manual switching, the
bi-directional DC/DC converter 401 will be disabled simultaneously.
The bi-directional DC/DC converter 401 can be disabled by the
control signal 1001 during maintenance or servicing.
[0032] The battery 101's temperature signal 1101 is also connected
to the bi-directional DC/DC converter 401. The bi-directional DC/DC
converter module 401 will adjust the charging or discharging
current in according to the signal 1101. The current distribution
between different levels of bi-directional DC/DC converter modules
is controlled through the current sharing signal bus 6, which can
be analog or digital signal bus. The current sharing signal bus 6
is bi-directional. The bi-directional DC/DC converter module 401
has a current sharing signal output which is bi-directional and
connected to the current sharing signal bus 6. Other bi-directional
DC/DC converter modules' current sharing signal outputs are
connected to the current sharing signal bus 6. The bi-directional
DC/DC converter module 401 will adjust its output current according
to the current sharing signal bus 6's voltage level or digital
signal. The voltage level or digital information of the current
sharing signal bus 6 represents the average load current for each
bi-directional DC/DC converter module. The bi-directional DC/DC
converter 401 will communicate with the BSM control bus through the
bi-directional bus 701. The outputs of the bi-directional DC/DC
converter modules are connected to a power bus 2. The power bus 2
connects the Energy Storage modules 1401 up to 140n, motor
controller 3 (which can be single or multiple), an internal
charging circuit 4 and an external charging circuit 5. The Energy
Storage modules 1401 to 140n are connected to the power bus 2
through the switch 501 to 50n respectively. The switches 501 to 50n
are electrically controlled by BMC module through control signals
1301 to 130n respectively. The number of energy storage module
activations is controlled by a program embedded in BMC. The energy
storage modules 1401 to 140n are configured to provide energy
buffers during charging and discharging. In the charging mode, it
will store energy from the external charging circuit, the
regenerative braking power, and the internal electricity
generator(s). This energy will be used to charge back batteries 101
to 10n through the bi-directional DC/DC converter modules 401 to
40n respectively. In the discharge mode, it will provide power and
energy to the motor controller as well as the surge load conditions
so that the bi-directional DC/DC converter modules 401 to 40n will
not be overloaded. The Battery Management Control (BMC) modules
1201 to 120n are connected and programmed in a redundancy
topology.
[0033] If any of the BMC modules failed, the other BMC modules will
seamlessly resume the functions of the failing module. The BMC
modules are connected to the BMS Control Bus 1 through the
bi-directional communication buses 1501 to 150n.
[0034] The switches 301 to 30n, 7, 8, and 9 are controlled by the
battery management control modules 1201 to 120n through the BMS
control bus. When the vehicle is parked, the switches 301 to 30n,
7, 8, and 9 are turned OFF. When the vehicle starts up before the
running condition, the switches 7 and 8 will be turned ON. The
switch 8 will be turned OFF if battery (or cell) charging is not
required. While external charging is required, the switch 9 will be
turned ON and the switches 7 and 8 will be turned OFF. This is to
prevent electrical over-stress to the motor controller 3 and the
internal electricity generator(s) 4 during external charging. If
the motor controller or electricity generator(s) are designed to be
able to withstand the stress, the switches 7 and 8 can be turned
ON.
[0035] Referring to FIG. 2, in this circuit implementation, the
battery status monitoring module assemblies (201, 201, . . . 20n)
form an integral part of the system. The Bus A connector is
connected to the BMS control bus. The connect/disconnect switch and
the bi-directional DC/DC converter module forms the bi-directional
DC/DC converter assembly which is an integral part of the systems.
The Bus B connector is connected to the BMS control bus. The
battery status monitoring module assemblies and bi-directional
DC/DC converter assemblies are connected to the BMS control bus.
The outputs of the bi-directional DC/DC converter assemblies are
connected to the DC power bus (2) in parallel with each other.
Likewise, the Battery management control modules are connected to
the BMS control bus through the respective Bus A and Bus B
connectors. The Bus C connector provides an interface between the
vehicle signal interface 10 to the battery management control
modules (1201, . . . , 120n) through the BMS control bus. The
vehicle signal interface 10 is a control interface to Energy
storage modules, internal charging circuits and external charging
circuits.
[0036] In the aforementioned embodiments, the fault tolerant
modular battery management system features multiple redundancy at
all module levels. These redundancy features allow concurrent
maintenance operations and provide multi-level fault tolerance.
Therefore, the modular battery management system has improved
reliability and availability. In addition, due to the modular
design framework, the modules at all levels can be manufactured
economically.
[0037] In the aforementioned embodiments, individual element or
module can be removed from or added to the MBMS without
interruption to the system availability. The battery pack (or cell)
can be removed from or added to the MBMS without interruption to
the system availability. The BSM module can be removed from or
added to the MBMS without interruption to the system availability.
The bi-directional DC/DC converter module can be removed from or
added to the MBMS without interruption to the system availability.
The Energy Storage module can be removed from or added to the MBMS
without interruption to the system availability. The BMC module can
be removed from or added to the MBMS without interruption to the
system availability.
[0038] In the aforementioned embodiments, the MBMS provides a
framework for EV or HEV or battery operated machines/equipments.
This framework can be used for different battery types, power bus
voltages, and output power requirements. The BSM and bi-directional
DC/DC converter module can be combined as a single module (or unit)
in a specific application. The battery packs (or cells) are
operated individually instead of serial connected in conventional
systems. The fault tolerant modular battery management system
resolves the battery pack (or cell) imbalance problem that exists
in conventional battery packs connected in series. The output
voltage to the power bus is determined by the bi-directional DC/DC
converter modules instead of the number of the battery packs (or
cells) connected in series. When some of the battery packs (or
cells) cannot provide an output power, the remaining battery packs
(or cells) can provide a limited output power at a rated voltage to
operate the motor driving circuits. The output current is provided
by the sum of individual bi-directional DC/DC converter output
currents.
[0039] In the aforementioned embodiments, during charging mode, the
energy is charged directly to Energy Storage (ES) module(s). This
can speed up the charging cycle. The stored energy in Energy
Storage (ES) module(s) then charges up the battery packs (or cells)
through the bi-directional DC/DC converter modules. The battery
packs (or cells) in the MBMS can operate in different modes of
operation simultaneously. This includes battery discharging,
battery charging, battery being connected to the MBMS and battery
being disconnected from the MBMS. The individual battery packs (or
cells) can be programmed in discharging or charging mode by the BMC
module. During vehicle driving mode, the energy fed by internal
electricity generator(s), regenerative braking and other power
generation devices can charge up some or all battery packs (or
cells) through the Energy Storage (ES) module(s) and bi-directional
DC/DC converter module(s). This extends the range of vehicle
traveling distance. The battery life span can be extended. MBMS
output capacity can be increased by the addition of battery Power
Conversion Modules (BPCM). The MBMS output capacity can be reduced
by removal of battery packs (or cells), or Battery Power Conversion
Modules (BPCMs). The MBMS output voltage can be adjusted by the
adjustment of bi-directional DC/DC converters output voltage. The
control algorithm embedded in the BMC module can be programmed for
individual battery pack charging, discharging and being
disconnected from the MBMS. The control algorithm inside the BMC
module can be programmed for different battery characteristics,
e.g., nickel-metal hydride NiHM, lithium-ion Li ion, lithium-ion
Polymer and etc. The BMC module can be interfaced with a driver
through a BMC display panel. Battery charging and discharging
status, remaining energy level, and alert for battery maintenance
information can be provided by the BMC display panel.
[0040] In the aforementioned embodiments, the batteries can be a
combination of different types. For example, Lead-acid and Lithium
batteries can operate in the system simultaneously. The
characteristic of high power density of lithium battery and deep
cycle discharge of Lead-acid battery can contribute to a longer
drive range.
[0041] While the present patent application has been shown and
described with particular references to a number of embodiments
thereof, it should be noted that various other changes or
modifications may be made without departing from the scope of the
present invention.
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