Apparatus and method for integrated control of a thermal management system

Abstract

An integrated apparatus and method for controlling a fluid pump and a valve connected to a coolant circuit is disclosed. A fluid pump is used to circulate fluid through the coolant circuit, and the valve is positionable between a first position and a second position. The controller generates control signals that are transmitted to the fluid pump and the valve for regulating the speed of the fluid pump and the speed of the fluid flow circulating through the coolant circuit and positioning the valve to the first position or the second position.

Description

Technical Field

[0001] The present invention relates generally to thermal management systems. More particularly, the present invention relates to an apparatus and method for providing integrated control of a fluid pump and valve used in a thermal management system. Background Art

[0002] Electric fluid pumps are known and are commonly used to move fluids in thermal management systems, such as coolants in vehicles. An example of a thermal management system is the cooling of a battery system of a hybrid or pure electric vehicle. The fluid pump operates at a number of different speeds to increase or decrease the flow of coolant through the thermal management system based on demand from the vehicle's central computer. A valve can be provided downstream of the fluid pump to regulate the flow of fluid from the pump, thereby ensuring the distribution of the coolant throughout the thermal management system. The valve can also be used to turn on or off the use of a variety of devices, such as the use of a chiller for the coolant. Each valve requires the use of an electric actuator to switch the flow of coolant through the valve. The valve actuator operates to move the valve component, thereby switching the flow of fluid through a number of different channels in the valve using a control signal from the vehicle's central computer. The electrical and control connections between each fluid pump and valve of the thermal management system and the vehicle's central computer use separate wiring harnesses to the multiple locations where the pumps and valves are located, resulting in complex wiring and high component costs. Summary of the invention

[0003] The present invention relates to an apparatus and method for providing integrated control of a fluid pump and valve used in a thermal management system.

[0004] In a first embodiment, an apparatus is disclosed that includes: a fluid pump connected to a coolant circuit that circulates a fluid through the coolant circuit; and a valve connected to the coolant circuit and arranged to be positionable / switched between a first position and a second position. A controller is operable to generate a control signal to the fluid pump that sets a rate at which the fluid flows through the coolant circuit, and to generate a control signal to the valve that positions the valve to the first position or the second position.

[0005] In a second embodiment, a method for controlling a fluid pump and a valve connected to a coolant circuit is disclosed, the fluid pump being used to circulate a fluid through the coolant circuit, and the valve being positionable between a first position and a second position, the method comprising generating a control signal by a controller, the control signal being transmitted to the fluid pump and the valve for regulating a speed of the fluid pump and a speed of a fluid flow circulated through the coolant circuit, and for positioning the valve to the first position or the second position.

[0006] Other technical features may be apparent to those skilled in the art from the following drawings, descriptions and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] For a more complete understanding of the present invention, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0008] Figure 1 A block diagram of an exemplary thermal management system of the present invention is shown;

[0009] Figure 2 An exemplary apparatus that may be used to perform integrated control of a fluid pump and valve used in the thermal management system of the present invention is shown;

[0010] Figure 3 An exemplary process controller of the present invention is shown;

[0011] Figure 4 an example flow chart showing the operational steps of the operating procedure of the present invention; and

[0012] Figure 5 An example of control block firmware that may be executed by the process controller of the present invention is shown. DETAILED DESCRIPTION

[0013] In this patent document, the accompanying drawings discussed below and the various embodiments used to describe the principles of the present invention are merely illustrative and should not be interpreted in any way as limiting the scope of the present invention. Those skilled in the art will appreciate that the principles of the present invention can be implemented in any type of appropriately arranged device or system.

[0014] It may be useful to describe a thermal management system in which the apparatus and methods of the present invention may be used. Figure 1 An exemplary thermal management system 10 for cooling a battery of a hybrid or pure electric vehicle is shown in a block diagram. The thermal management system 10 uses a coolant loop to maintain desired temperature conditions of a vehicle battery 16, in which the coolant flow rate and flow direction are controlled by a separate electrically driven fluid pump 12 and a separate electrically driven valve 20, respectively. The coolant loop of the thermal management system 10 positions the fluid pump 12 and the temperature sensor 14 upstream of a battery heat exchanger 18 attached to the vehicle battery 16. The valve 20 has an input connected to a line 19 downstream of the heat exchanger 18. A cooler module 25 is connected to an outlet port A of the valve 20 via a line 21 downstream of the valve 20. The line 21 passes through the cooler 25 and is connected to a line 29 and a downstream input or suction input of the fluid pump 12. The valve 20 can also be operated to switch the fluid flow leaving the outlet port B to the line 27, thereby switching the coolant loop to flow to the auxiliary heat exchanger 28. The fluid pump 12 receives a suction input of fluid to the fluid pump from the auxiliary heat exchanger 28 via a line 29 .

[0015] The battery heat exchanger 18 transfers heat generated by the battery 16 to the coolant fluid flowing through the heat exchanger 18, and the pump motor 65 drives the fluid pump 12. The pump motor 65 is electrically operated to close, open, and rotate when turned on at a variety of different speeds by regulating pulse width modulation (PWM) of the voltage applied to the motor terminals. The pump motor 65 causes the pumping components of the fluid pump 12, such as the impeller, to receive fluid from the coolant circuit at the suction port connected to line 29 and discharge the fluid from the outlet connected to line 13. The sensor 14 attached to line 13 measures the temperature of the coolant fluid entering the battery heat exchanger 18 and provides readings that determine the operating settings for the outlet port of the valve 20 and the speed (flow) of the fluid pump 12 required to achieve the desired temperature state. The fluid flow from the heat exchanger 18 reaches the valve 20 via line 19. At Figure 1 In the example of FIG. 1 , valve 20 is shown with its first outlet port A connected to line 21, which connects a cooler module 25 to the cooling circuit in a first position. With valve 20 in the first position, fluid flow is directed to cooler module 25, which will reduce the temperature of the coolant. The cooled coolant is then returned to fluid pump 12 via lines 21 and 29 to be further moved by fluid pump 12 through battery heat exchanger 18, thereby continuing the cooling cycle.

[0016] If the battery 16 does not require adequate cooling, the valve 20 can be operated to a second position in which the cooling circuit is connected from the outlet port B of the valve 20 to the auxiliary heat exchanger 28. The auxiliary heat exchanger 28 can be part of a cabin heater system, part of a window defog system, or simply part of a cooling system that passes air through the heat exchanger 28 to reduce the heat contained in the coolant without requiring cooling. The cooled coolant is then returned to the fluid pump 12 via lines 27 and 29 to move further through the battery heat exchanger 18.

[0017] Although Figure 1 One example of a thermal management system 10 is shown, but other examples may be used. Figure 1 Many variations are possible. For example, the thermal management system may include any number of pumps, valves, heat exchangers, coolers, and other components. Furthermore, Figure 1 The composition and arrangement of system 10 in FIG. 1 are for illustrative purposes only. Components may be added, omitted, combined, or placed in any other suitable configuration, depending on particular needs. In addition, specific functions have been described as being performed by specific components of system 10, which is for illustrative purposes only. In general, thermal management systems are highly configurable and may be configured in any suitable manner, depending on particular needs.

[0018] Figure 2An exemplary device is shown that can be used to implement the integrated control of the fluid pump 12 and the valve 20 of the thermal management system 10 of the present invention. The integrated control of the fluid pump 12 and the valve 20 is provided by a control system 50. The control system 50 may include a process controller 55 and motor drivers 60 and 70, and the control system 50 is communicatively connected to one or more motors 65 and 75 through the motor drivers 60 and 70, respectively. The motors 65 and 75 may include pump motors, valve actuators, actuable switches (e.g., solenoids), positioners, etc. In the present invention, the motor driver 60 provides power and control signals to the motor 65 that drives the fluid pump 12. Similarly, the motor driver 70 provides power and control signals to the motor 75 used as a valve actuator to position the valve 20.

[0019] The position sensor 76 is electrically or mechanically connected to the valve actuator motor 75, and provides a feedback signal of the current position of the valve actuator motor 75 to the process controller 55 through the line 77. The sensor 76 can be an electrical device that generates a DC voltage representing the position of the valve actuator motor 75, which corresponds to the outlet port A or the outlet port B of the valve 20. For example, when the valve 20 is in the first position, the coolant flows out of the outlet port A, and the valve sensor 76 can provide a 4V DC voltage as a feedback signal to the process controller 55, indicating that the valve outlet port A is open and the valve outlet port B is closed. Similarly, the feedback signal is a 1V DC voltage can indicate that the valve outlet port A is closed and the valve outlet port B is open.

[0020] A speed (RPM) sensor 66, such as a magnetic pickup, a Hall Effect device, or an optical sensor device, may be attached to the pump motor 65 to provide a voltage or current (amperage) feedback signal of the RPM of the pump motor 65, which is indicative of the actual speed of the pump motor 65. The RPM signal is fed back from the sensor 66 to the process controller 55 via line 67. A vehicle computer 80 is connected to the process controller 55 via a communications bus 85, and the vehicle computer 80 sends control commands to the process controller 55. The vehicle computer also receives status reports of valve position, pump motor speed and power, and diagnostic data indicative of errors detected by the control system 50.

[0021] Figure 3 An exemplary process controller 55 according to the present invention is shown. Figure 3As shown, the process controller 55 may include a bus system 305 that supports communication between at least one central processing unit (CPU) 310, at least one storage device 315, at least one communication unit 320, and at least one input / output (I / O) unit 325. The CPU 310 executes instructions that may be loaded into a memory 330 or a permanent storage device 335 of the storage device 315. The CPU 310 may include any suitable number and type of processors or other devices in any suitable arrangement. Example types of central processing units 310 include microprocessors, microcontrollers, digital signal processors, field programmable gate arrays, application specific integrated circuits, and discrete circuits.

[0022] The memory 330 and the permanent storage device 335 are examples of the storage device 315, which represent any structure capable of storing information (such as data, program code and / or other suitable temporary or permanent information) and facilitating retrieval of the information. The memory 330 may represent a random access memory (RAM) or any other suitable volatile or non-volatile storage device, and the permanent storage device 335 may include one or more components or devices that support long-term storage of data, such as a read-only memory (ROM) or flash memory. The storage device 315 may include a computer program or instructions executable by the CPU 310 and suitable for controlling the pump motor 65 of the fluid pump 12 and the valve actuator motor 75 of the valve 20. The memory 330 or the permanent storage device 335 may also include a computer program or instructions executable by the CPU 310 and suitable for detecting the actual position of the valve actuator motor 75 and the actual RPM of the motor 65 generated by the sensors 76 and 66, respectively.

[0023] The communication unit 320 supports communication with other systems or devices. For example, the communication unit 220 may include a network interface for communicating with the vehicle computer 80 via the network 85. Control signals in the form of serial control signals or control packets may be sent from the vehicle computer 80 to the communication unit 320 for use by the CPU 310. Similarly, the communication unit 320 may transmit data and reports from the CPU 310 or the storage device 315 to the vehicle computer 80. For example, the process controller 55 may send a report confirming receipt of commands and control signals sent from the vehicle computer 80 to the process controller 55, and return a report confirming the actual position of the valve 20 and the speed of the fluid pump 12 to the vehicle computer 80. The communication unit 320 may also send diagnostic data of the operating conditions of the motors 65 and 75 to the vehicle computer 80.

[0024] The I / O unit 325 allows control signals and data to be input and output between the process controller 55 and external devices. For example, the I / O unit 325 is connected to the device drivers 60 and 70 to issue commands to the device drivers 60 and 70 to drive and control the operation of the pump motor 65 and the valve actuator motor 75. The device drivers 60 and 70 are connected to the device drivers 60 and 70 to drive and control the operation of the pump motor 65 and the valve actuator motor 75. Figure 3 3. Although shown as two separate devices in FIG. 3, however, the device driver may also be a single device having driver sections 60 and 70 electrically separated from each other. In addition, the I / O unit 325 is communicatively connected to feedback signals generated by the rotation speed sensor 66 and the position sensor 76.

[0025] It should be noted that the present invention uses the process controller 55 and individual components as examples to explain the invention of the present invention, and those skilled in the art will understand that other devices can also be used for the process controller 55, such as a microcontroller, or an application specific integrated circuit (ASIC) that can combine the CPU 310, memory 330, and I / O units into a single integrated device.

[0026] stored in memory 330 and Figure 4 The operating program 400 shown in FIG. 4 is executed by the CPU 310 to provide integrated control of the pump motor 65 of the fluid pump 12 and the valve actuator motor 75 of the valve 20. The speed value of the pump motor 65 and the position value of the valve actuator motor 75 are both contained in a plurality of control blocks stored in the memory 330. Figure 5 An example of control block firmware 500 that may be executed by the process controller 55 is shown. Control blocks 510, further arbitrarily identified as 1.00 to 2.00 and 3.00 to 4.00, provide multiple increment blocks of pump motor PWM values, valve motor on / off values, valve sensor position values, and valve outlet port A and valve outlet port B opening values. Each increment represents a control value block for the pump motor 65 and valve actuator motor 75. The process controller 55 may receive a command input from the vehicle computer 80 that identifies the control values ​​to be generated by the pump motor 65 and the valve actuator motor 75. Figure 4 The operating program 400 will use the data contained in the control block of the firmware 500 to set the speed of the pump motor 65 and the position of the valve actuator motor 75 to position the outlet ports A and B of the valve 12.

[0027] It should also be noted that for the purpose of explaining the present invention, Figure 5Only a small set of incremental control blocks are shown in the example of . Those skilled in the art will appreciate that the control blocks can be subdivided into more increments. For example, the increments can be subdivided to provide control values ​​for every 5% or 10% of the pump motor PWM. The control blocks can also include control blocks for more than one pump motor or more than one actuator motor that can be used in a thermal management system. In addition, incremental control blocks can be provided for valve port settings that allow mixed output flows from valve outlet ports A and B, which can be used in complex thermal management systems.

[0028] Figure 4 The example method of FIG. 4 shows the operation steps of the operating program 400 executed by the CPU 310. In operation step 410, the process controller receives a command input from the vehicle computer 80 via the communication unit 320, and the CPU 310 interprets the command input and locates the firmware 500 control block associated with the input command stored in the memory 330.

[0029] First, in operation 415, the CPU 310 retrieves the currently set speed of the pump motor 65. This can be accomplished by reading the RPM of the pump motor from the RPM sensor 66 or by reading the pump motor data stored in the memory 330 from the last executed control block. If the requested motor speed is different from the currently set pump motor speed, then in operation 420, a control signal is sent to the pump motor driver 60 to establish a new pump speed. For example, if the input command from the vehicle computer 80 requests execution of control block 1.40, then the pump motor 65 will need to be set to a pump speed of 40%, see Figure 5 .

[0030] If the current motor pump speed provided by the RPM sensor 66 or if the set pump speed from the last data block execution is different than the new requested pump speed, the motor driver 60 is signaled to increase or decrease the pump motor PWM until 40% of the new pump speed is reached. When the pump motor speed reaches the new pump speed, as reported by the feedback signal from the RPM sensor 66, the program jumps to operation 425. If the new command input requests the same pump speed as the currently set pump speed, the program continues to operation 425 without performing operation 420.

[0031] Next in operation 425, the current position of the valve 20 is determined. This can be accomplished by reading a feedback signal from the sensor 76, which provides a sensor voltage that is different from the voltage reference, as described above. The difference in the sensed voltages represents the actual position of the actuator motor 75. The current position of the valve 20 can also be determined by using the last sensed sensor voltage stored in the memory 330 from the last executed control block.

[0032] If the requested valve position is different from the currently set valve position, the program determines the currently set valve actuator motor polarity in order to properly turn the valve in the correct direction. Figure 1 The illustrated valve 20 is shown placed in a first position directing coolant flow through outlet port A. To place the valve outlet from outlet port B to outlet port A in the previous operation, a forward voltage polarity would have been applied to the valve actuator motor 75, causing the valve actuator motor 75 to rotate in a clockwise direction. To place the valve in a second position directing fluid through outlet port B, the valve actuator motor 75 must rotate counterclockwise. Therefore, a reverse voltage polarity must be applied to the valve actuator motor 75 to cause the valve actuator motor 75 to rotate counterclockwise. The data stored in the memory 330 from the last executed command input will also save the current polarity of the valve actuator motor 75, which can be used to determine the correct rotation for positioning the valve 20.

[0033] Once the motor polarity is established, a control signal is sent to the valve actuator motor driver 70 in operation 435 to turn the valve actuator motor 75 in the correct direction to achieve the new valve position. For example, in our example where the vehicle computer 80 requests execution of control block 1.40, the valve actuator motor 75 needs to be set to open valve outlet port B 100%, see Figure 5 If the current differential voltage provided by the valve position sensor 76 is different from the requested valve position defined in control block 1.40, the valve actuator motor 70 is signaled to turn in the direction established in operation 430 to place the valve in the second position and allow 100% flow from the valve 20 through outlet port B. When the motor actuator 76 reaches valve position B, the valve position sensor 76 provides a 1 volt DC voltage feedback signal to the CPU 310, establishing that the valve is now in the second position and the program jumps to operation 440. If the new command input requests the same valve position as the currently set valve position, the program continues to operation 440 without performing operations 430 and 435. In step 440, the process controller 55 sends a report to the vehicle computer 80 to confirm the position of the valve 12 and the speed (flow rate) of the fluid pump 12.

[0034] It may be advantageous to clarify the definitions of certain words and phrases used throughout this patent document. The term "connected" and its derivatives include direct and indirect connections. The terms "include" and "comprises" and their derivatives mean including but not limited to. The term "or" is inclusive and means and / or. The phrase "associated with..." and its derivatives may mean including, included within, interconnected, containing, contained within, connected to or connected with, connected to or connected with, communicable with, coordinated with, interlaced, juxtaposed, close to, combined with or combined with, having, having the attributes of, having a relationship with, etc. When used with a list of items, the phrase "at least one" means that different combinations of one or more of the listed items may be used, and only one item in the list may be required. For example, "at least one of A, B, C" includes any combination of: A, B, C, A and B, A and C, B and C, A and B and C.

[0035] The description in this application should not be construed as implying that any particular element, step, or function is an essential or critical element that must be included within the scope of the claims. The scope of the subject matter for which patent rights are claimed is limited only by the claims that allow. In addition, no claim is intended to invoke 35 U.S.C. §112(f) with respect to any appended claim or claim element unless the exact words "means for..." or "step for..." are expressly used in a particular claim, followed by a participle phrase identifying the function. The use of terms such as (but not limited to) "mechanism", "module", "device", "unit", "component", "element", "member", "device", "machine", "system", or "controller" in the claims shall be understood and intended to refer to structures known to those skilled in the relevant art, further modified or enhanced by the features of the claims themselves, and are not intended to invoke 35 U.S.C. §112(f).

[0036] Although the present invention has described certain embodiments and generally associated methods, the changes and arrangements of these embodiments and methods will be apparent to those skilled in the art. Therefore, the above description of the exemplary embodiments does not define or restrict the present invention. Other changes, substitutions and variations are also possible without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A device comprising: a fluid pump connected to the coolant circuit for circulating a fluid through the coolant circuit; a valve connected to the coolant circuit, the valve being arranged to be positionable between a first position and a second position; and A controller is operable to generate a control signal to the fluid pump to set a rate at which fluid flows through the coolant circuit and to generate a control signal to the valve to position the valve to a first position or a second position.

2. The device according to claim 1, wherein: The controller comprises: Central Processing Unit (CPU); a memory connected to the central processing unit; and An operating program stored in the memory, the operating program, when executed by the central processing unit, generates a control signal for setting a rate of fluid flow through the coolant circuit and a control signal for positioning the valve to the first position or the second position.

3. The device according to claim 3, wherein: The controller also includes: a communication unit connected to a vehicle computer arranged to transmit commands to the controller; and An input / output unit is arranged to receive control signals generated by the operating program.

4. The device according to claim 2, wherein: The memory also includes control block firmware organized in incremental blocks of control values, wherein the commands from the vehicle computer select control blocks and control block values ​​to be executed by the operating program.

5. The device according to claim 4, wherein: The control values ​​include data for setting a rate of fluid flow produced by the pump motor.

6. The device according to claim 5, wherein: The control value includes data for positioning the valve in the first position or the second position.

7. The device according to claim 6, wherein: The fluid pump is driven by a pump motor connected to a pump motor driver, the input / output unit being communicatively connected to the pump motor driver, wherein the pump motor driver is arranged to receive control signals from the input / output unit and to send a voltage to the pump motor, the voltage setting the speed of the pump motor and the rate of fluid flow through the coolant circuit.

8. The device according to claim 6, wherein: The valve is driven by an electric actuator motor connected to an actuator motor driver, and the input / output unit is communicatively connected to the actuator motor driver, wherein the actuator motor driver is arranged to receive control signals from the input / output unit and to send a voltage to the valve actuator motor for positioning the valve in the first position or the second position.

9. The device according to claim 7, wherein: The pump motor is connected to a pump motor sensor which provides a feedback signal of the actual speed of the pump motor to the input / output unit.

10. The device according to claim 8, wherein: The actuator motor is connected to an actuator motor sensor that provides a feedback signal to the controller that the valve is in a first position or a second position.

11. The device according to claim 8, wherein: Before positioning the valve in the first position or the second position, the controller determines the rotation direction of the actuator motor and sends a control signal to the actuator motor driver to cause the actuator motor driver to generate a voltage polarity for rotating the actuator motor clockwise or a voltage polarity for rotating the actuator motor counterclockwise.

12. The device according to claim 10, wherein: The operating program sends a report to the vehicle computer using the communication unit to confirm the speed of the pump motor and the first position or the second position of the valve.

13. The device according to claim 9, wherein: The feedback signal sent by the pump motor sensor communicates the rotational speed of the pump motor.

14. The device according to claim 10, wherein: The feedback signal generated by the actuator motor is represented by a DC voltage based on the position of the valve.

15. A method for controlling a fluid pump and a valve connected to a coolant circuit, the fluid pump for circulating a fluid through the coolant circuit, the valve being positionable between a first position and a second position, the method comprising; Control signals are generated by a controller and transmitted to the fluid pump and the valve for adjusting the speed of the fluid pump and the speed of the fluid flow circulating through the coolant circuit and for positioning the valve to the first position or the second position.

16. The method according to claim 15, wherein: The controller comprises: Central Processing Unit (CPU); and A memory connected to the central processing unit, the method further comprising: An operating program stored in memory is executed by the central processing unit, which generates the control signal, which adjusts the speed of the fluid pump and the speed of fluid flow through the coolant circuit and adjusts the position of the valve to the first position or the second position.

17. The method according to claim 16, wherein: The central processing unit receives commands from a vehicle computer, the memory further comprising control block firmware stored in the memory, the control block firmware being organized in incremental blocks of control values, the method further comprising: selecting control blocks and values ​​for control blocks based on commands received by the central processing unit from the vehicle computer; and The control signal is generated by the operating program using the value of the control block.

18. The method according to claim 17, wherein: The control values ​​include data for setting a rate of fluid flow through the coolant circuit produced by the fluid pump.

19. The method according to claim 17, wherein: The control value includes data for positioning the valve in the first position or the second position.

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