Apparatus and method for integrated control of a thermal management system

Abstract

An integrated device and method for controlling a fluid pump and a valve connected to a coolant loop are disclosed. A fluid pump for circulating fluid through the coolant loop, and a valve positionable between a first and a second position. A controller generates control signals transmitted to the fluid pump and the valve to regulate the speed of the fluid pump and the flow of the fluid circulated through the coolant loop, and to position the valve in either the first or the second position.

Description

Technical Field

[0001]

[0001] This disclosure generally relates to thermal management systems. More particularly, this disclosure relates to apparatus and methods for providing integrated control of fluid pumps and valves used in thermal management systems.

Background Art

[0002]

[0002] Electric fluid pumps are known and are widely used to move fluids within thermal management systems, such as coolant within a vehicle. One example of a thermal management system is the cooling of a battery system in a hybrid or fully electric vehicle. Fluid pumps are operated at various speeds to increase or decrease the flow of coolant through the thermal management system based on requests from a vehicle central computer. Valves can be used downstream of the fluid pump to regulate the flow from the pump to ensure the distribution of coolant throughout the thermal management system. Valves can also be used to switch the start and stop of the use of various devices, such as a cooling device for cooling 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 valve components to switch the flow through various passages within the valve using control signals from the vehicle central computer. The electrical and control connections between each fluid pump and valve in the thermal management system and the vehicle central computer use separate wiring harnesses to various locations where the pumps and valves are located, resulting in wiring complexity and high component costs.

Summary of the Invention

[0003]

[0003] This disclosure relates to apparatus and methods for providing integrated control of fluid pumps and valves used in thermal management systems.

[0004] In a first embodiment, there is disclosed an apparatus comprising a fluid pump connected to a coolant loop for circulating a fluid through the coolant loop, and a valve connected to the coolant loop and arranged to be positionable between a first and a second position. A controller is operable to generate a control signal for the fluid pump that sets the flow rate of the fluid through the coolant loop, and a control signal for the valve that positions the valve in either the first or the second position.

[0004]

[0005] In a second embodiment, a method for controlling a fluid pump and a valve connected to a coolant loop is disclosed, the fluid pump being for circulating a fluid through the coolant loop, the valve being positionable between a first and a second position, the method comprising the step of generating, by a controller, control signals transmitted to the fluid pump and the valve that regulate the speed of the fluid pump and the flow of the fluid circulating through the coolant loop and position the valve in either the first or the second position.

[0005]

[0006] Other technical features may become readily apparent to those skilled in the art from the following figures, description, and claims.

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

Brief Description of the Drawings

[0006]

Figure 1

[0008] It is a block diagram of an exemplary thermal management system of the present disclosure.

Figure 2

[0009] It is a diagram illustrating an example of an apparatus that can be used for integrated control of a fluid pump and a valve used in the thermal management system of the present disclosure.

Figure 3

[0010] It is a diagram illustrating an example of a process controller of the present disclosure.

Figure 4

[0011] It is a flowchart illustrating an example of the operation steps of the operation program of the present disclosure.

Figure 5

[0012] FIG. is an example of control block firmware executable by a process controller of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0007]

[0013] The figures discussed below, and the various embodiments used to explain the principles of the present invention within this patent document, are for illustrative purposes only and should not be construed in any way as limiting the scope of the present invention. Those skilled in the art will understand that the principles of the present invention can be implemented in any type of suitably arranged device or system.

[0008]

[0014] It may be useful to describe a thermal management system in which the devices and methods of the present disclosure can be used. FIG. 1 illustrates a block diagram of an exemplary thermal management system 10 for cooling a battery of a hybrid or fully electric vehicle. The thermal management system 10 uses a coolant loop to maintain desired temperature conditions of the vehicle's battery 16. In this example, the coolant flow and direction of flow are controlled by one independent electric fluid pump 12 and one independent electrically actuated 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 conduit 19 downstream of the heat exchanger 18. The cooling device module 25 is connected to the outlet port A of the valve 20 downstream of the valve 20 via a conduit 21. The conduit 21 passes through the cooling device 25 and is connected to the conduit 29 and the inlet input or suction input of the fluid pump 12. The valve 20 can also be operated to switch the flow exiting from the outlet port B to the conduit 27, switching the coolant loop to flow to the auxiliary heat exchanger 28. The fluid pump 12 receives fluid from the auxiliary heat exchanger 28 to the suction input of the fluid pump via the conduit 29.

[0009]

[0015] The battery heat exchanger 18 transfers the heat generated by the battery 16 to the coolant fluid flowing through the heat exchanger 18. The electric pump motor 65 drives the fluid pump 12. The pump motor 65 is electrically operated to rotate when turned off, turned on, and turned on at various speeds by adjusting the pulse width modulation (PWM) of the voltage applied across the motor terminals. The electric pump motor 65 receives fluid from the coolant loop at the suction input connected to the conduit 29 and discharges the fluid from the outlet connected to the conduit 13 to the pumping component of the fluid pump 12, such as an impeller. The sensor 14 mounted on the conduit 13 measures the temperature of the coolant fluid entering the battery heat exchanger 18 and determines the speed (flow) of the fluid pump 12 required to reach the operating settings for the valve 20 outlet port and the desired temperature condition. The flow from the heat exchanger 18 arrives at the valve 20 via the conduit 19. In the example of FIG. 1, the valve 20 is shown having a first outlet port A connected to the conduit 21 that connects the cooling device module 25 to the cooling loop in the first position. With the valve 20 in the first position, the flow is directed towards the cooling device module 25 that lowers the temperature of the coolant. The cooled coolant then returns to the fluid pump 12 via the conduits 21 and 29 so as to be further moved across the battery heat exchanger 18 by the fluid pump 12 to continue the cooling cycle.

[0010]

[0016] When the battery 16 does not require substantial cooling, the valve 20 can be operated to a second position that connects the cooling loop from the outlet port B of the valve 20 to the auxiliary heat exchanger 28. The auxiliary heat exchanger 28 may be part of a cabin heater system, part of a window anti-fogging system, or part of a cooling system that passes air through the heat exchanger 28 to reduce the heat contained in the coolant without the need for cooling. The cooled coolant then returns to the fluid pump 12 via the conduits 27 and 29 so as to be further moved across the battery heat exchanger 18.

[0011]

[0017] FIG. 1 illustrates one example of a thermal management system 10, but various changes can be made to FIG. 1. For example, the thermal management system can include any number of pumps, valves, heat exchangers, cooling devices, and other components. Also, the configuration and arrangement of system 10 within FIG. 1 are for illustration purposes only. Components can be added, omitted, combined, or placed in any other suitable configuration according to specific requirements. Further, specific functions are described as being performed by specific components of system 10. This is for illustration purposes only. Generally, the thermal management system is highly configurable and can be configured in any suitable manner according to specific requirements.

[0012]

[0018] FIG. 2 illustrates an example of an apparatus that can be used to effect integrated control of a fluid pump 12 and a valve 20 of the thermal management system 10 of the present disclosure. The integrated control of the fluid pump 12 and the valve 20 is provided by a control system 50. The control system 50 can include a process controller 55, as well as motor drive devices 60 and 70. The control system 50 is communicatively coupled to one or more motors 65 and 75 via motor drive devices 60 and 70, respectively. Motors 65 and 75 can include a pump motor, a valve actuator, an operable switch (e.g., a solenoid), a positioning device, and the like. In the present disclosure, device drive device 60 provides power and control signals to an electric motor 65 that drives fluid pump 12. Similarly, device drive device 70 provides power and control signals to an electric motor 75 that acts as a valve actuator to position valve 20.

[0013]

[0019] The position sensor 76 is electrically or mechanically connected to the valve actuator motor 75 that provides a feedback signal of the current position of the valve actuator motor 75 to the process controller 55 via line 77. The sensor 76 may be an electrical device that generates an electrical DC voltage representing the position of the valve actuator motor 75 corresponding 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 from the outlet port A, and the valve sensor 76 may provide a voltage of 4vDC to the process controller 55 as a feedback signal indicating that the valve outlet port A is open and the valve outlet port B is closed. Similarly, a feedback signal of 1vDC may indicate that the valve outlet port A is closed and the valve outlet port B is open.

[0014]

[0020] An RPM sensor 66, such as a magnetic pickup, a Hall effect device, or an optical sensor device, may be mounted on the pump motor 65 to provide a voltage or current (ampere) feedback signal of the RPM of the pump motor 65. The RPM feedback signal represents the actual speed of the pump motor 65. The RPM signal is returned from the sensor 66 to the process controller 55 via line 67. The vehicle computer 80 is connected to the process controller 55 via the communication bus 85. The vehicle computer 80 transmits control commands to the process controller 55. The vehicle computer also receives diagnostic data representing the progress report of the valve position, the pump motor speed and power, and the errors detected by the control system 50.

[0015]

[0021] Figure 3 illustrates an example process controller 55 according to the present disclosure. As shown in FIG. 3, 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 read into memory 330 or persistent storage 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 processing devices 310 include microprocessors, microcontrollers, digital signal processors, field programmable gate arrays, application specific integrated circuits, and discrete circuits.

[0016]

[0022] Memory 330 and persistent storage 335 are examples of storage device 315 that represents any structure capable of temporarily or persistently storing information (such as data, program code, and / or other suitable information) or facilitating retrieval of information. Memory 330 may represent random access memory (RAM) or any other suitable volatile or non-volatile storage device. Persistent storage 335 may include one or more components or devices that support long-term storage of data, such as read-only memory (ROM) or flash memory. The storage device 315 may include computer programs 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. Memory 330 or persistent storage 335 may further include computer programs 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.

[0017]

[0023] The communication unit 320 supports communication with other systems or devices. For example, the communication unit 220 may include a network interface for communication to the vehicle computer 80 through the network 85. Control data in the form of serial control signals or packets of control signals may be transmitted 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 verifying receipt of commands and control signals transmitted from the vehicle computer 80 to the process controller 55, and return a report verifying 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 transmit diagnostic data on the operating health of the motors 65 and 75 to the vehicle computer 80.

[0018]

[0024] The I / O unit 325 enables the input and output of control signals and data between the process controller 55 and external devices. For example, the I / O unit 325 connects to the device drivers 60 and 70 to issue commands for driving and controlling the operation of the pump motor 65 and the valve actuator motor 75. The device drivers 60 and 70 are shown as two separate devices in FIG. 3, but the device drivers may be a single device having driver regions 60 and 70 that are electrically isolated from each other. Additionally, the I / O unit 325 is communicatively connected to feedback signals generated by the RPM sensor 66 and the position sensor 76.

[0019]

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

[0020]

[0026] The operation program 400 stored in the memory 330 and shown in FIG. 4 is executed by the CPU 310 to provide integrated control of both the fluid pump 12, the pump motor 65 and the valve 20, the valve actuator motor 75. Both the speed value of the pump motor 65 and the position value of the valve actuator motor 75 are included in a plurality of control blocks stored in the memory 330. FIG. 5 illustrates an example of control block firmware 500 that can be executed by the process controller 55. Control blocks 510, arbitrarily identified further as 1.00 - 2.00 and 3.00 - 4.00, provide a plurality of 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 open values. Each increment represents a block of control values for both the pump motor 65 and the valve actuator motor 75. The process controller 55 can receive a command input from the vehicle computer 80 to identify the control block to be used by the operation program of FIG. 4. The operation program 400 uses the data included in the control blocks of the firmware 500 to set the pump motor 65 speed, and the position of the valve actuator motor 75 that positions the outlet ports A and B of the valve 20 as a result.

[0021]

[0027] It should be further noted that only a small set of increment control blocks are shown in the example of FIG. 5 to facilitate the description of the present disclosure. It is to be understood by those skilled in the art that the control blocks can be subdivided into more increments. For example, the increments can be subdivided to provide control values every 5% or 10% of the pump motor PWM. The control blocks can also include control blocks for two or more pump motors or two or more actuator motors that can be used in a thermal management system. Additionally, the increment control block can be provided for valve port settings that enable a mixed output flow from both valve outlet ports A and B, which can be used in a complex thermal management system.

[0022]

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

[0023]

[0029] First, in operation 415, the CPU 310 obtains the current set speed of the pump motor 65. This can be done either by reading the RPM of the pump motor from the RPM sensor 66 or from the pump motor data stored in the memory 330 from the last executed control block. If the required motor speed is different from the currently set pump motor speed, a control signal is sent to the pump motor drive 60 in operation 420 to establish a new pump speed. For example, if the input command from the vehicle computer 80 requests that control block 1.40 be implemented, as seen in FIG. 5, the pump motor 65 needs to be set to a pump speed of 40%.

[0024]

[0030] In the case of the current motor pump speed provided by the RPM sensor 66, or when the pump speed set since the last data block execution is different from the newly requested pump speed, the motor drive 60 is signaled to increase or decrease the pump motor PWM until 40% of the new pump speed is achieved. As reported by the feedback signal from the RPM sensor 66, when the pump motor speed reaches the new pump speed, the program immediately moves to operation 425. If the new command input requests a pump speed that is the same as the currently set pump speed, the program continues to operation 425 without executing operation 420.

[0025]

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

[0026]

[0032] If the required valve position is different from the currently set valve position, the program determines the currently set valve actuator motor polarity to rotate the valve appropriately in the correct direction. For example, valve 20 shown in FIG. 1 is shown placed in a first position directing the coolant flow through outlet port A. In the previous operation, a forward voltage polarity to valve actuator motor 75 was applied to place the valve outlet from outlet port B to outlet port A, rotating valve actuator motor 75 in the clockwise direction. To place the valve in a second position directing the flow through outlet port B, valve actuator motor 75 must rotate counterclockwise. Therefore, a reverse voltage polarity must be applied to valve actuator motor 75 to rotate it counterclockwise. Data stored in memory 330 from the last executed command input also stores the current polarity of valve actuator motor 75 that can be used to determine the appropriate rotation to position valve 20.

[0027]

[0033] Once the motor polarity is established, the control signal is sent to the valve actuator motor drive 70 in operation 435 to rotate the valve actuator motor 75 in the appropriate direction to achieve a new valve position. For example, in an example of the present invention where the vehicle computer 80 requests that control block 1.40 be implemented, the valve actuator motor 75 needs to be set to have a fully open valve outlet port B as seen in FIG. 5. If the current differential voltage provided by the valve position sensor 76 is different from the required valve position defined in control block 1.40, the valve actuator motor 70 is signaled to rotate in the direction established in operation 430 to place the valve in a second position and pass 100% of the flow of valve 20 to outlet port B. When the motor actuator 76 reaches valve position B, the valve position sensor 76 provides a 1vDC feedback signal to the CPU 310 establishing that the valve is now in the second position, and the program immediately moves to operation 440. If a new command input requests a valve position that is the same as the currently set valve position, the program continues to operation 440 without executing operations 430 and 435. In step 440, the process controller 55 sends a report to the vehicle computer 80 verifying the valve 20 position and the speed (flow rate) of the fluid pump 12.

[0028]

[0034] It may be advantageous to define certain terms and expressions used throughout this patent document. The term "communicate", and its derivatives, encompasses both direct and indirect communication. The terms "include" and "comprise", and their derivatives, mean inclusion without limitation. The term "or" is inclusive and means and / or. The expression "associated with", and its derivatives, may mean "including", "included within", "interconnected with", "containing", "contained within", "connected to or with", "coupled to or with", "capable of communicating with", "cooperating with", "interleaving", "parallelizing", "proximal to", "tied to or with", "having the property of", "relating to or having a relationship with", or the like. The expression "at least one of" when used with a list of items means that one or more different combinations of the listed items may be used and that only one of the items in the list may be required. For example, "at least one of A, B, and C" includes any of the combinations: A, B, C, A and B, A and C, B and C, and A and B and C.

[0029]

[0035] The description in this application should not be read as suggesting that any particular element, step, or function is an essential or critical element that must be included in the claims. The scope of the claimed subject matter is defined only by the allowed claims. Further, no claim is intended to invoke 35 U.S.C. § 112, ¶ 6, with respect to any appended claim or claim element, unless the exact phrase "means for" or "step for" is expressly used in that claim before the clause that recites the identified function. The use of terms such as "mechanism", "module", "device", "unit", "component", "element", "member", "apparatus", "machine", "system", or "controller" (but not limited to these) within a claim is understood and intended to refer to structures known to those of ordinary skill in the art such that the claim itself is further amended or enhanced by the characteristics of the claim, and no claim is intended to invoke 35 U.S.C. § 112, ¶ 6.

[0030]

[0036] This disclosure describes particular embodiments and generally associated methods, but alternatives and modifications of these embodiments are to be understood as being apparent to those of ordinary skill in the art. Accordingly, the foregoing description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alternatives are also possible without departing from the spirit and scope of this disclosure as defined by the following claims.

Claims

1. A fluid pump connected to the coolant loop for circulating fluid through the coolant loop, A valve connected to the coolant loop, arranged to be positionable between a first position and a second position, A controller operable to generate a control signal for the fluid pump to set the flow rate of the fluid through the coolant loop and a control signal for the valve to position the valve in either the first position or the second position An apparatus comprising.

2. The controller comprises A central processing unit (CPU), A memory connected to the CPU, An operation program stored in the memory, which, when executed by the CPU, generates the control signal to set the flow rate of the fluid through the coolant loop and position the valve in either the first position or the second position. The apparatus according to claim 1.

3. The controller further comprises A communication unit connected to a vehicle computer, the vehicle computer being arranged to transmit commands to the controller, An I / O unit arranged to receive the control signal generated by the operation program. The apparatus according to claim 3.

4. The memory further comprises control block firmware configured within an increment block of control values, and the command from the vehicle computer selects the control block and its values to be executed by the operation program. The apparatus according to claim 2.

5. The control value includes data for setting the flow rate of the fluid provided by the pump motor. The apparatus according to claim 4.

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

7. The fluid pump is driven by an electric pump motor connected to a pump motor drive device and an I / O unit communicably connected to the pump motor drive device. The pump motor drive device is arranged to receive the control signal from the I / O unit and transmit to the pump motor the speed of the pump motor and the voltage for setting the flow rate through the coolant loop. The apparatus according to claim 6.

8. The valve is driven by an electric actuator motor connected to an actuator motor drive device and an I / O unit communicably connected to the actuator motor drive device. The actuator motor drive device is arranged to receive the control signal from the I / O unit and transmit a voltage for positioning the valve in either the first position or the second position to the valve actuator motor. The device according to claim 6.

9. The pump motor is connected to a pump motor sensor that provides a feedback signal of the actual speed of the pump motor to the I / O unit. The device according to claim 7.

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

11. The controller determines a direction for rotating the actuator motor and transmits a control signal to the actuator motor drive device that generates a voltage polarity for rotating the actuator motor clockwise or a voltage polarity for rotating the actuator motor counterclockwise before positioning the valve in either the first position or the second position. The device according to claim 8.

12. The operation program uses a communication unit to send a report to the vehicle computer to check the speed of the pump motor and the first or second position of the valve. The device according to claim 10.

13. The feedback signal transmitted by the pump motor sensor communicates the RPM of the pump motor. The device according to claim 9.

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

15. A method for controlling a fluid pump and a valve connected to a coolant loop, the fluid pump for circulating fluid through the coolant loop, the valve being positionable between a first position and a second position. A method comprising the steps of generating, by a controller, a control signal to adjust the speed of the fluid pump and the flow of fluid circulating through the coolant loop, and to position the valve in either the first position or the second position, and transmitting the control signal to the fluid pump and the valve.

16. The controller comprises a central processing unit (CPU), and a memory connected to the CPU, and the method further comprises executing, by the CPU, an operating program stored in the memory to generate the control signal for adjusting the speed of the fluid pump, the fluid flow through the coolant loop, and the position of the valve to either the first position or the second position, the method according to claim 15.

17. The CPU receives commands from a vehicle computer, the memory further comprises control block firmware stored in the memory configured within an increment block of control values, and the method further comprises selecting a control block and its values based on the commands received by the CPU from the vehicle computer, and using the control block values to generate the control signal by the operating program, the method according to claim 16.

18. The control values include data for setting the flow rate of the fluid through the coolant loop provided by the fluid pump, the method according to claim 17.

19. The control values include data for positioning the valve in the first or second position, the method according to claim 17.

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