U.S. patent application number 13/790387 was filed with the patent office on 2014-09-11 for system and method for ambient temperature sensing of a pump system.
The applicant listed for this patent is REGAL BELOIT AMERICA, INC.. Invention is credited to Justin M. Magyar.
Application Number | 20140250580 13/790387 |
Document ID | / |
Family ID | 51485927 |
Filed Date | 2014-09-11 |
United States Patent
Application |
20140250580 |
Kind Code |
A1 |
Magyar; Justin M. |
September 11, 2014 |
SYSTEM AND METHOD FOR AMBIENT TEMPERATURE SENSING OF A PUMP
SYSTEM
Abstract
A pump system including a motor, a fluid pump powered by the
motor, a temperature sensor, and a controller. The controller
including a processor and a computer readable memory storing
instructions that, when executed by the processor, cause the
controller to receive a first temperature value from the
temperature sensor, receive a second temperature value from the
temperature sensor, calculate a rate of temperature change by
comparing the first temperature value and the second temperature
value, calculate a heating offset value based on the rate of
temperature change, and calculate an ambient temperature based on
the second temperature value and the heating offset value.
Inventors: |
Magyar; Justin M.; (Troy,
OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
REGAL BELOIT AMERICA, INC. |
Beloit |
WI |
US |
|
|
Family ID: |
51485927 |
Appl. No.: |
13/790387 |
Filed: |
March 8, 2013 |
Current U.S.
Class: |
4/494 ; 417/32;
417/63 |
Current CPC
Class: |
F04D 15/00 20130101;
F04D 15/0077 20130101; F04D 15/0088 20130101 |
Class at
Publication: |
4/494 ; 417/32;
417/63 |
International
Class: |
F04D 15/00 20060101
F04D015/00 |
Claims
1. A pump system comprising: a motor a fluid pump powered by the
motor; a temperature sensor; and a controller including a processor
and a computer readable memory storing instructions that, when
executed by the processor, cause the controller to receive a first
temperature value from the temperature sensor, receive a second
temperature value from the temperature sensor, calculate a rate of
temperature change by comparing the first temperature value and the
second temperature value, calculate a heating offset value based on
the rate of temperature change, and calculate an ambient
temperature based on the second temperature value and the heating
offset value.
2. The pump system of claim 1, wherein the instructions, when
executed by the processor, further cause the controller to receive
a third temperature value from the temperature sensor, calculate an
updated rate of temperature change by comparing the second
temperature value and the third temperature value, calculate an
updated heating offset value based on the updated rate of
temperature change, and calculate an updated ambient temperature
based on the third temperature value and the updated heating offset
value.
3. The pump system of claim 1, wherein there is a predetermined
time period between receiving the first temperature value and the
second temperature value.
4. The controller of claim 1, wherein the instructions, when
executed by the processor, further cause the controller to
determine if the rate of temperature change is above a
predetermined upper rate of temperature change threshold and below
a predetermined lower rate of temperature change threshold, wherein
if the rate of temperature change is above the predetermined rate
of temperature change threshold or below the predetermined lower
rate of temperature change threshold the controller does not
calculate the ambient temperature based on the heating offset
value.
5. The pump system of claim 1, wherein the temperature sensor is
located outside a housing of the pump system.
6. The pump system of claim 1, wherein the instructions, when
executed by the processor, further cause the controller to activate
the motor to begin pumping of fluid when the ambient temperature is
below a freeze protection temperature threshold.
7. The pump system of claim 1, wherein the instructions, when
executed by the processor, further cause the controller to indicate
an error condition when the temperature value from the temperature
sensor exceeds an overheat temperature threshold.
8. The pump system of claim 1, further including a user-interface
module.
9. The pump system of claim 8, wherein the temperature sensor is
integrated into the user-interface module.
10. A method of determining an ambient temperature of a pump
system, the pump system including a motor, a fluid pump powered by
the motor, and a temperature sensor, the method comprising:
receiving a first temperature value from the temperature sensor;
receiving a second temperature value from the temperature sensor;
calculating a rate of temperature change by comparing the first
temperature value and the second temperature value; calculating a
heating offset value based on the rate of temperature change; and
calculating an ambient temperature based on the second temperature
value and the heating offset value.
11. The method of claim 10, further comprising receiving a third
temperature value from the temperature sensor, calculating an
updated rate of temperature change by comparing the second
temperature value and the third temperature value, calculating an
updated heating offset value based on the updated rate of
temperature change, and calculating an updated ambient temperature
based on the third temperature value and the updated heating offset
value.
12. The method of claim 10, wherein there is a predetermined time
period between receiving the first temperature value and the second
temperature value.
13. The method of claim 10, further comprising determining if the
rate of temperature change is above a predetermined upper rate of
temperature change threshold and below a predetermined lower rate
of temperature change threshold, wherein if the rate of temperature
change is above the predetermined rate of temperature change
threshold or below the predetermined lower rate of temperature
change threshold not calculating the ambient temperature based on
the heating offset value.
14. The method of claim 10, further comprising activating the motor
to begin pumping of fluid when the ambient temperature is below a
freeze protection temperature threshold.
15. A pool system comprising a vessel; and a pump system including
a motor, a fluid pump powered by the motor, a temperature sensor,
and a controller including a processor and a computer readable
memory storing instructions that, when executed by the processor,
cause the controller to receive a first temperature value from the
temperature sensor, receive a second temperature value from the
temperature sensor, calculate a rate of temperature change by
comparing the first temperature value and the second temperature
value, calculate a heating offset value based on the rate of
temperature change, and calculate an ambient temperature based on
the second temperature value and the heating offset value.
16. The controller of claim 15, wherein the instructions, when
executed by the processor, further cause the controller to receive
a third temperature value from the temperature sensor, calculate an
updated rate of temperature change by comparing the second
temperature value and the third temperature value, calculate an
updated heating offset value based on the updated rate of
temperature change, and calculate an updated ambient temperature
based on the third temperature value and the updated heating offset
value.
17. The pump system of claim 15, wherein there is a predetermined
time period between receiving the first temperature value and the
second temperature value.
18. The controller of claim 15, wherein the instructions, when
executed by the processor, further cause the controller to
determine if the rate of temperature change is above a
predetermined upper rate of temperature change threshold and below
a predetermined lower rate of temperature change threshold, wherein
if the rate of temperature change is above the predetermined rate
of temperature change threshold or below the predetermined lower
rate of temperature change threshold the controller does not
calculate the ambient temperature based on the heating offset
value.
19. The pump system of claim 15, wherein the temperature sensor is
located outside a housing of the pump system.
20. The pump system of claim 15, wherein the instructions, when
executed by the processor, further cause the controller to activate
the motor to begin pumping of fluid when the ambient temperature is
below a freeze protection temperature threshold.
21. The pump system of claim 15, wherein the instructions, when
executed by the processor, further cause the controller to indicate
an error condition when the temperature value from the temperature
sensor exceeds an overheat temperature threshold.
22. The pump system of claim 15, further including a user-interface
module.
23. The pump system of claim 22, wherein the temperature sensor is
integrated into the user-interface module.
Description
BACKGROUND
[0001] The invention relates to methods for sensing an ambient
temperature of a pump system.
SUMMARY
[0002] Pump systems often utilize a temperature sensor for sensing
an ambient temperature. The temperature sensor may often sense a
temperature that is higher than the true ambient temperature due to
heat exposure from direct sunlight. The exposure to direct sunlight
causes a sunlight load on the temperature sensor. The sunlight load
increases the sensed temperature values leading to false
temperature readings. In order to limit sunlight load, some pump
system manufacturers require the pump system to be located in a
shaded area at all times. Other pump system manufacturers use a
sensor located on or near the electronics board inside a housing of
the pump system. This sensor uses predetermined offsets to account
for electronic and motor heating. An alternative is desired.
[0003] In one embodiment, the invention provides a pump system
comprising a motor; a fluid pump powered by the motor; a
temperature sensor; and a controller. The controller including a
processor and a computer readable memory storing instructions that,
when executed by the processor, cause the controller to receive a
first temperature value from the temperature sensor, receive a
second temperature value from the temperature sensor, calculate a
rate of temperature change by comparing the first temperature value
and the second temperature value, calculate a heating offset value
based on the rate of temperature change, and calculate an ambient
temperature based on the second temperature value and the heating
offset value.
[0004] In another embodiment the invention provides a method of
determining an ambient temperature of a pump system, the pump
system including a motor, a fluid pump powered by the motor, and a
temperature sensor. The method comprising receiving a first
temperature value from the temperature sensor; receiving a second
temperature value from the temperature sensor; calculating a rate
of temperature change by comparing the first temperature value and
the second temperature value; calculating a heating offset value
based on the rate of temperature change; and calculating an ambient
temperature based on the second temperature value and the heating
offset value.
[0005] Other aspects of the invention will become apparent by
consideration of the detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 schematically illustrates a pool or spa system
according to one embodiment of the invention.
[0007] FIG. 2 illustrates a controller of the pool system of FIG.
1.
[0008] FIG. 3 illustrates a perspective view of the controller, a
motor, and a user-interface module of the pool system of FIG.
1.
[0009] FIGS. 4a-4c illustrate an operation of determining a sensed
ambient temperature of the pool system of FIG. 1, according to one
embodiment of the invention.
DETAILED DESCRIPTION
[0010] Before any embodiments of the invention are explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
constructions and of being practiced or of being carried out in
various ways.
[0011] FIG. 1 schematically illustrates a pool or spa system 100.
The pool system 100 includes a vessel 105, a pump system 110, and a
controller 115. In some constructions, the vessel 105 is a hollow
container such as a tub, pool, or vat that holds a fluid. In some
constructions, the fluid is chlorinated water.
[0012] The pump system 110 includes a motor 120, a fluid pump 125,
and a fluid agitator 130. In one construction, the motor 120 is a
brushless direct-current (BLDC) motor. As is commonly known, BLDC
motors include a stator, a permanent magnet rotor, and an
electronic commutator. The electronic commutator typically
includes, among other things, a programmable device (e.g., a
microcontroller, a digital signal processor, or a similar
controller) having a processor and memory. The programmable device
of the BLDC motor uses software stored in the memory to control the
electronic commutator. The electric commutator then provides the
appropriate electrical energy to the stator in order to rotate the
permanent magnet rotor at a desired speed. In other constructions,
the motor 120 can be a variety of other types of motors, including
but not limited to, a brush direct-current motor, a stepper motor,
a synchronous motor, an induction motor, a vector-driven motor, a
switched reluctance motor, and other DC or AC motors. In some
constructions, the motor 120 is a variable speed motor. In other
constructions, the motor 120 can be a multi-speed motor or a single
speed motor.
[0013] The motor 120 is coupled to the fluid pump 125 by a shaft or
similar connector. The fluid agitator 130 is contained within the
fluid pump 125. In some constructions, the fluid agitator 130 is a
rotor, such as an impeller or a fan. In operation, the motor 120
rotates the fluid agitator 130 located within the fluid pump 125.
As the fluid agitator 130 is rotated, the fluid agitator 130
controllably moves the fluid contained by the vessel 105 through
the pool system 100. Other pump systems having other fluid
agitators may be used without departing from the spirit of the
invention.
[0014] FIG. 2 illustrates the controller 115 of the pool system
100. The controller 115 is electrically and/or communicatively
connected to a variety of modules or components of the pool system
100. For example, the controller 115 is connected to the motor 120.
The controller 115 includes combinations of hardware and software
that are operable to, among other things, control the operation of
the pool system 100.
[0015] In some constructions, the controller 115 is the same
controller already contained within the motor 120, therefore having
one controller that both directly controls the speed of the motor
120 and the operation of the pool system 100. In other
constructions, the controller 115 is a separate controller from the
controller contained within the motor 120 and controls the
operation of the pool system 100 while controlling the controller
contained within the motor 120, therefore having two separate
controllers. An exemplary controller 115 and motor 120 combination
is described in U.S. patent application Ser. No. 13/285,624, filed
on Oct. 31, 2011, the entire content of which is incorporated
herein by reference.
[0016] In some constructions, the controller 115 includes a
plurality of electrical and electronic components that provide
power, operational control, and protection to the components and
modules within the controller 115 and pool system 100. For example,
the controller 115 includes, among other things, a processor 150
(e.g., a microprocessor, a microcontroller, or another suitable
programmable device) and a memory 155. In some constructions, the
controller 115 is implemented partially or entirely on a
semiconductor (e.g., a field-programmable gate array ["FPGA"]
semiconductor) chip.
[0017] The memory 155 includes, for example, a program storage and
a data storage. The program storage and the data storage can
include combinations of different types of memory, such as
read-only memory ("ROM"), random access memory ("RAM") (e.g.,
dynamic RAM ["DRAM"], synchronous DRAM ["SDRAM"], etc.),
electrically erasable programmable read-only memory ("EEPROM"),
flash memory, a hard disk, an SD card, or other suitable magnetic,
optical, physical, or electronic memory devices. The processor unit
150 is connected to the memory 155 and executes software
instructions that are capable of being stored in a RAM of the
memory 155 (e.g., during execution), a ROM of the memory 155 (e.g.,
on a generally permanent basis), or another non-transitory computer
readable medium such as another memory or a disc. Software included
in the implementation of the pool system 100 can be stored in the
memory 155 of the controller 115. The software includes, for
example, firmware, one or more applications, program data, filters,
rules, one or more program modules, and other executable
instructions. The controller 115 is configured to retrieve from
memory and execute, among other things, instructions related to the
control processes and methods described herein. In other
constructions, the controller 115 includes additional, fewer, or
different components.
[0018] The controller 115 receives power from a power supply module
160. The power supply module 160 supplies a nominal AC or DC
voltage to the controller 115 or other components or modules of the
pool system 100. The power supply module 160 is powered by, for
example, a power source having nominal line voltages between 110V
and 240V AC and frequencies of approximately 5-060 Hz. The power
supply module 160 is also configured to supply lower voltages to
operate circuits and components within the controller 115 or pool
system 100. In other constructions, the controller 115 or other
components and modules within the pool system 100 are powered by
one or more batteries or battery packs, or another grid-independent
power source (e.g., a generator, a solar panel, etc.).
[0019] The controller 115 is controlled and monitored by a
user-interface module 165. For example, the user-interface module
165 is operably coupled to the controller 115 to control the
operating speed of the motor 120, the duration of operation of the
motor 120, etc. The user-interface module 165 includes a
combination of digital and analog input or output devices required
to achieve a desired level of control and monitoring for the pool
system 100. For example, the user-interface module 165 includes a
display (e.g., a primary display, a secondary display, etc.) and
input devices such as touch-screen displays, a plurality of knobs,
dials, switches, buttons, etc. The display is, for example, a
liquid crystal display ("LCD"), a light-emitting diode ("LED")
display, an organic LED ("OLED") display, an electroluminescent
display ("ELD"), a surface-conduction electron-emitter display
("SED"), a field emission display ("FED"), a thin-film transistor
("TFT") LCD, etc. The user-interface module 165 can also be
configured to display conditions or data associated with the pool
system 100 in real-time or substantially real-time. In some
implementations, the user-interface module 165 is controlled in
conjunction with the one or more indicators (e.g., LEDs, speakers,
etc.) to provide visual or auditory indications of the status or
conditions of the pool system 100. In some constructions, the
user-interface module 165 is integrated into the same housing as
the controller 115, or part of a control board of the controller
115.
[0020] The controller 115 is further in electrical communication
with a temperature sensor 170. The temperature sensor 170 can be a
digital temperature sensor or an analog temperature sensor. In some
constructions, the temperature sensor 170 is a resistive
temperature device (e.g., negative temperature coefficient ["NFC"],
positive temperature coefficient ["PTC"], etc.). In other
constructions, the temperature sensor 170 can be a variety of other
types of temperature sensors, including but not limited to,
thermocouples, infrared sensors, bimetallic devices, thermometers,
and change-of-state sensors. In some constructions, the temperature
sensor 170 is incorporated into the user-interface module 165. In
other constructions, the temperature sensor 170 is located on a
housing of the pump system 110.
[0021] FIG. 3 illustrates a perspective view of one construction of
the controller 115, the motor 120, and the user-interface module
165 of the pool system 100.
[0022] In operation, the controller 115 receives sensed temperature
values from the temperature sensor 170 at a predetermined frequency
(e.g., every 1 second, 5 seconds, 10 second, 30 seconds, 1 min, 2
min, 5 min, 10 min, 15 min, 30 min, or a frequency of approximately
between 1 second to 30 min). The controller 115 uses the received
temperature values to calculate a rate of temperature change (e.g.,
a rate of temperature rise if the sensed temperature values are
increasing, or a rate of temperature fall if the sensed temperature
values are decreasing). If the rate of temperature rise is greater
than a predetermined value (e.g., an increase of 3.degree. C.
during a 15 min time period), the controller 115 determines that
the sensed temperature rise is due to sunlight load, rather than an
increase in ambient temperature. If the rate of temperature fall is
greater than a predetermined value (e.g., a decrease of 1.degree.
C. during a 15 min time period), the controller 115 determines that
the sensed temperature fall is due to a temporary departure of
sunlight load (e.g., temporary cloud cover of the sun), rather than
a decrease in ambient temperature. If the temperature change is
determined to be due to sunlight load or temporary departure of
sunlight load, the controller 115 uses the rate of temperature
change to calculate a heating offset. The heating offset, along
with the most recent received temperature value, is then used by
the controller 115 to calculate an ambient temperature. The
controller 115 continually repeats the operation to update the
heating offset and the ambient temperature.
[0023] In some constructions, the controller 115 uses a heating
offset cap. In situations when the ambient temperature is
relatively high, the sunlight load can be over accounted for.
Therefore, a heating offset cap is used to maintain the heating
offset at a reasonable value. The heating offset cap is a
predetermined cap value that the heating offset cannot surpass. If
the calculated heating offset is greater than the predetermined cap
value, then the predetermined cap value, along with the most recent
received temperature value, is used to calculate the sensed ambient
temperature.
[0024] FIGS. 4a-4c illustrate an operation or method 200 of
determining an ambient temperature. The controller 115 sets the
heating offset to zero (Step 205). The controller 115 receives a
first temperature value from the temperature sensor 170 (Step 210).
The controller 115 waits for a predetermine time period (e.g., 1
min, 2 min, 5 min, 10 min, 15 min, 30 min, or approximately 1 min
to 30 min) (Step 215). The controller 115 receives a second
temperature value from the temperature sensor 170 (Step 220). The
controller 115 calculates a rate of temperature change by
subtracting the first temperature value from the second temperature
value (Step 225). The controller 115 determines if the rate of
temperature change is greater than, or equal to, a predetermined
heating rise value (Step 230). If the rate of temperature change is
greater than, or equal to, the predetermined heating rise value,
the controller 115 adds the rate of temperature change to a heating
offset (Step 235). The controller 115 then determines if the
heating offset is greater than, or equal to, a heating offset cap
(Step 240). If the heating offset is greater than, or equal to, the
heating offset cap, the controller 115 subtracts the heating offset
cap from the second temperature value to calculate the ambient
temperature (Step 245), the method 200 then returns to Step 210. If
the heating offset is not greater than, or equal to, the heating
offset cap, the controller 115 subtracts the heating offset from
the second temperature value to calculate the ambient temperature
(Step 250), the method 200 then returns to Step 210.
[0025] If the controller determines NO in Step 225, the controller
determines if the rate of temperature change is less than a
predetermined heating fall value (Step 255). If the rate of
temperature change is not less than the predetermined heating fall
value, the controller 115 subtracts the heating offset from the
second temperature value to calculate the ambient temperature (Step
260), the method 200 then returns to Step 210. If the rate of
temperature change is less than the predetermined heating fall
value, the controller 115 adds the rate of temperature change to
the heating offset (Step 265). The controller 115 determines if the
heating offset is a negative number (Step 270). If the heating
offset is a negative number the method returns to Step 205. If the
heating offset is a positive number, the controller 115 subtracts
the heating offset from the second temperature value to calculate
the ambient temperature (Step 275), the method 200 then returns to
Step 210.
[0026] When the pool system 100 operates in colder climates or
during colder temperatures, water flowing within the pump system
110 may freeze. Frozen water within the pump system 110 prevents
the pump system 110 from operating properly. Furthermore, because
freezing water expands, frozen water can cause damage to the pool
system 100. One way to prevent water from freezing within the pump
system 110 is to operate the motor 120 and force water to move
through the pool system 100 instead of remaining stagnant. In some
constructions, if the sensed ambient temperature is below a
predetermined freeze protection temperature threshold, the
controller 115 activates the motor 120 to begin pumping of
fluid.
[0027] Thus, the invention provides, among other things, a system
and method for ambient temperature sensing of a pump system.
Various features and advantages of the invention are set forth in
the following claims.
* * * * *