Controlling the temperature of the vehicle's electric drive system

Abstract

Aspects and embodiments of the present invention relate to a control system, system, vehicle, method, and computer-readable instructions for controlling the temperature of an electric drive system (208) of a vehicle (1). Each method includes: receiving a first signal indicating the temperature of the electric drive system (208) of the vehicle (1); receiving a second signal indicating the temperature of a thermal management system of the vehicle (1); comparing the first signal with the second signal; and outputting a control signal to control heat exchange between the electric drive system (208) and the thermal management system, wherein the control signal depends on the comparison.

Description

Technical Field

[0001] This disclosure relates to controlling the temperature of an electric drive system for a vehicle. Aspects of the invention relate to control systems, systems, vehicles, methods, and computer-readable instructions. Background Technology

[0002] It is known to provide means for suppressing heat exchange between the electric drive system (e.g., electric drive unit) and the thermal management system (e.g., coolant system) of an electric vehicle based on the absolute temperature of the electric drive system. This allows for rapid preheating of the electric drive system during cold start scenarios. The object of the present invention is to overcome one or more disadvantages associated with the prior art. Summary of the Invention

[0003] The various aspects and embodiments of the present invention provide control systems, systems, vehicles, methods, and computer-readable instructions as claimed in the appended claims.

[0004] According to one aspect of the present invention, a control system for controlling the temperature of an electric drive system of a vehicle is provided, the control system comprising one or more processors, said one or more processors being configured to:

[0005] Receive a first signal indicating the temperature of the vehicle's electric drive system;

[0006] Receive a second signal indicating the temperature of the vehicle's thermal management system;

[0007] Compare the first signal with the second signal; and

[0008] The output control signal controls the heat exchange between the electric drive system and the thermal management system, wherein the control signal depends on the comparison.

[0009] The advantage of using control signals based on a comparison of the temperature of the electric drive system with the temperature of the thermal management system (e.g., a vehicle-grade coolant system), rather than the absolute temperature of the electric drive system, lies in improved thermal management. For example, because the temperatures will deviate from each other, various thermal management scenarios during a driving cycle (trip) can be considered. For instance, the control system can determine whether to guide (start or significantly increase) or inhibit (stop or significantly reduce) the fluid flow through the heat exchanger between the electric drive system and the thermal management system. If one system in the system requires additional thermal energy, and the other system is hotter, flow can be guided through the heat exchanger to operate the hotter system as a heat source. However, if the other system is colder, flow through the heat exchanger can be inhibited. Similarly, if one system in the system needs to remove thermal energy, and the other system is colder, flow can be guided through the heat exchanger to use the colder system as a radiator. However, if the other system is hotter, flow through the heat exchanger can be inhibited.

[0010] The control system includes one or more controllers, which collectively include: at least one electronic processor having electrical inputs for receiving input signals; and at least one memory device electrically coupled to the at least one electronic processor and having instructions stored therein; and wherein the at least one electronic processor is configured to access the at least one memory device and execute the instructions on the at least one memory device to: receive a first signal; receive a second signal; output a control signal; and any one or more of other optional controller functions or method steps described herein.

[0011] Optionally, the thermal management system may include a vehicle-grade coolant system for supplying coolant to several modules, including modules for the electric drive system.

[0012] Optionally, the control signals may include valve control signals and / or pump control signals to control fluid flow through a heat exchanger used to exchange heat energy between the electric drive system and the thermal management system. Optionally, the control signals may be configured to selectively direct or inhibit fluid flow through the heat exchanger.

[0013] The advantage is that the fluid flow through the heat exchanger can be stopped and started, or increased and decreased.

[0014] Optionally, the control signal may include a valve control signal. Optionally, the valve control signal may be configured to control a bypass valve. The bypass valve may be an active bypass valve. Optionally, the valve control signal may be configured to cause the bypass valve to control the fluid flow through the heat exchanger relative to the fluid flow through a bypass passage that bypasses the heat exchanger.

[0015] The advantage of controlling how much fluid flows around the heat exchanger instead of controlling the pump is that the pump can continue to operate, allowing the lubricant to circulate within the electrically driven system.

[0016] Optionally, the valve control signal can be configured to guide fluid flow through the heat exchanger by controlling the state of the bypass valve to select a fluid passage including the heat exchanger. Optionally, the valve control signal can be configured to suppress fluid flow through the heat exchanger by controlling the state of the bypass valve to select a bypass fluid passage to bypass the heat exchanger.

[0017] If the pump is controlled, the pump control signal can optionally be configured to direct the fluid flow through the heat exchanger by controlling the pump to generate a fluid flow through a fluid circuit including the heat exchanger. The pump control signal can optionally be configured to suppress the fluid flow through the heat exchanger by controlling the pump to suppress the fluid flow in the fluid circuit including the heat exchanger.

[0018] Optionally, the first signal may indicate the lubricant temperature of the electric drive system. Optionally, the lubricant temperature may be the oil temperature. Optionally, the electric drive system may be fully oil-cooled or substantially oil-cooled. Optionally, the first signal may depend on a temperature measurement performed by a lubricant temperature sensor of the electric drive system. Optionally, the lubricant temperature sensor may be configured to measure the temperature in the lubricant circuit of the electric drive system.

[0019] The advantage is that the first signal indicates whether the electric drive system is cold, thus affecting efficiency due to factors such as lubricant viscosity and winding temperature. Advantageously, the first signal also indicates whether the electric drive system is overheated, thus affecting efficiency and the durability of components such as windings, bearings, insulation, wiring, and seals.

[0020] Optionally, the second signal can indicate the coolant temperature of the thermal management system. Optionally, the second signal can depend on the temperature measurement of the coolant temperature sensor of the thermal management system. Optionally, the coolant temperature sensor can be configured to measure the temperature in the coolant circuit of the thermal management system.

[0021] The advantage is that the second signal indicates the coolant temperature, and therefore the amount of thermal energy available for any module thermally coupled to the thermal management system, such as the electric drive system, traction battery cooler, and / or climate control module.

[0022] Optionally, the comparison may include a reactivity comparison based on the first and second signals. The temperature may be a real-time temperature.

[0023] The advantage is that the control system can compare the current temperature to determine whether to guide or inhibit the flow of fluid through the heat exchanger.

[0024] Optionally, the control system can be configured to determine whether to trigger a thermal protection condition for regulating the temperature of the electric drive system, wherein the control signal depends on whether the thermal protection condition is triggered. Optionally, the control signal is output based on a positive determination (triggering the thermal protection condition). Optionally, when the determination is negative (not triggered by the thermal protection condition), the control signal can be output based on different conditions or requests.

[0025] The advantage lies in improved thermal protection, because it identifies the need for thermal protection of the electric drive system, and then, as previously described, the control system compares the temperatures on both sides of the heat exchanger to determine whether to guide or inhibit the flow of fluid through the heat exchanger in order to provide thermal protection for the electric drive system.

[0026] Optionally, thermal protection conditions may include overheat protection conditions for detecting and / or predicting overheating of the electric drive system. Additionally or alternatively, thermal protection conditions may include cold protection conditions that depend on the temperature of the electric drive system.

[0027] The advantage is that the temperature of the electric drive system can be optimized under both hot and cold (e.g., freezing) conditions.

[0028] If the overheat protection condition is met, and a comparison indicates that the temperature of the electric drive system is higher than the temperature of the thermal management system, the control signal may optionally be configured to direct the fluid flow through the heat exchanger. If the overheat protection condition is met, and a comparison indicates that the temperature of the thermal management system is higher than the temperature of the electric drive system, the control signal may optionally be configured to suppress the fluid flow through the heat exchanger.

[0029] The advantage is that the heat exchanger will only be used if it is capable of cooling the electric drive unit.

[0030] If the cold protection condition is met, and a comparison indicates that the temperature of the thermal management system is higher than the temperature of the electric drive system, the control signal may optionally be configured to direct the fluid flow through the heat exchanger. If the cold protection condition is met, and a comparison indicates that the temperature of the thermal management system is lower than the temperature of the electric drive system, the control signal may optionally be configured to suppress the fluid flow through the heat exchanger.

[0031] The advantage is that the heat exchanger will only be used if it is capable of preheating the electric drive unit.

[0032] Optionally, the overheat protection condition may include a reactive overheat protection condition that depends on the temperature of the electric drive system. Optionally, the satisfaction of the reactive overheat protection condition may be based on the absolute temperature of the electric drive system. Optionally, the reactive overheat protection condition may depend on a first signal. Optionally, the reactive overheat protection condition may include an overheat temperature threshold, based on the temperature exceeding the threshold to satisfy the condition. Optionally, the threshold may be an absolute temperature threshold based on the absolute temperature.

[0033] Alternatively or additionally, overheat protection conditions may optionally include predictive overheat protection conditions depending on a signal indicating the operating point of the electric drive system. The operating point may optionally indicate a requested load of the electric drive system, such as a power request. Optionally, predictive overheat protection conditions may include an operating point threshold, based on the operating point exceeding the threshold to satisfy the condition.

[0034] The advantage lies in the ability to proactively manage the temperature of the electric drive system, thereby extending the period during which the electric drive system can operate at high operating points (speed, load) without thermal derating. Therefore, by initiating control of heat exchange based on the operating point before exceeding the overheating temperature threshold, the electric drive system can operate at high operating points for an extended period without reaching the overheating temperature threshold or a higher derating threshold.

[0035] Optionally, the satisfaction of the cold protection condition may be based on the absolute temperature of the electric drive system. For example, a reactive cold protection condition may optionally depend on a first signal. The cold protection condition may optionally be a reactive cold protection condition. The cold protection condition may optionally include a cold temperature threshold, based on the condition being satisfied when the temperature drops below the threshold. The cold temperature threshold may optionally be an absolute temperature threshold based on the absolute temperature. The cold temperature threshold may optionally be a value below zero degrees Celsius.

[0036] In summary, based on the examples above, the control signal depends on which of the multiple sub-conditions satisfying the thermal protection condition and the comparison thereof. In some, but not necessarily all, examples, the sub-conditions include one or more of the reactive overheat protection condition, the predictive overheat protection condition, and the cold protection condition described above.

[0037] Optionally, thermal protection conditions may include thresholds set to define a hysteresis control strategy. For example, one or more of the previously described thresholds may optionally depend on whether fluid flow is currently being directed through the heat exchanger or being inhibited through the heat exchanger. For example, one or more of the previously described thresholds may optionally depend on the state of a bypass valve.

[0038] The advantage is that the hysteresis control strategy prevents excessive valve switching, also known as chattering.

[0039] Optionally, the control system can be configured to receive a third signal based on a thermal regulation request. Optionally, the thermal regulation request can be based on an energy efficiency algorithm, and optionally on a vehicle-level energy efficiency algorithm.

[0040] Optionally, whether to output additional control signals for controlling heat exchange based on the thermal regulation request depends on whether the thermal protection condition is triggered. Optionally, additional control signals are output if the determination of whether the thermal protection condition is triggered is negative.

[0041] The advantage is that the control system can accept lower-priority thermal regulation requests as long as thermal protection is not required. Thermal regulation refers to heating or cooling the thermal management system or modules thermally connected to the thermal management system, such as the electric drive system, traction battery cooler, and / or climate control module, for thermal regulation purposes. The purpose of thermal regulation can be energy optimization or comfort, and is unrelated to thermal protection.

[0042] According to another aspect of the invention, a system is provided comprising a control system and an electric drive system, wherein the electric drive system includes a lubricant circuit, a coolant-lubricant heat exchanger thermally connecting the coolant circuit to the lubricant circuit, a bypass passage bypassing the coolant-lubricant heat exchanger, and an active bypass valve capable of being controlled by a control signal based on a comparison to control the fluid flow rate through the coolant-lubricant heat exchanger relative to the fluid flow rate through the bypass passage. Optionally, the system may further include a lubricant temperature sensor. Advantages are as described above.

[0043] According to another aspect of the invention, a vehicle is provided that includes a control system or system.

[0044] According to another aspect of the present invention, a method for controlling the temperature of an electric drive system of a vehicle is provided, the method comprising:

[0045] Receive a first signal indicating the temperature of the vehicle's electric drive system;

[0046] Receive a second signal indicating the temperature of the vehicle's thermal management system;

[0047] Compare the first signal with the second signal; and

[0048] The output control signal controls the heat exchange between the electric drive system and the thermal management system, wherein the control signal depends on the comparison. The advantages are as described above.

[0049] According to another aspect of the invention, a computer-readable instruction is provided, which, when executed by a computer, is configured to perform any or more of the methods described herein. According to another aspect of the invention, a non-transitory computer-readable medium comprising computer-readable instructions, which, when executed by one or more electronic processors, cause the one or more electronic processors to perform any or more of the methods described herein.

[0050] According to another aspect of the invention, a control system for controlling the temperature of an electric drive system of a vehicle is provided, the control system comprising one or more processors configured to:

[0051] Receive a first signal indicating the temperature of the vehicle's electric drive system; and

[0052] Based on a first signal indicating that the temperature is below a threshold, a control signal is output to suppress heat exchange between the vehicle's electric drive system and thermal management system. The advantage is that it defines the cold protection conditions.

[0053] According to another aspect of the invention, a control system for controlling the temperature of an electric drive system of a vehicle is provided, the control system comprising one or more processors configured to:

[0054] Receive a first signal indicating the requested operating point of the electric drive system; and

[0055] Based on the first signal, a control signal is output to control the heat exchange between the vehicle's electric drive system and thermal management system. The advantage is that it defines predictive overheat protection conditions.

[0056] Within the scope of this application, it is expressly intended that the various aspects, embodiments, examples, and alternatives set forth in the preceding paragraphs, in the claims, and / or in the following description and drawings, and in particular their various features, may be adopted independently or in any combination falling within the scope of the appended claims. That is, all embodiments and / or features of any embodiment may be combined in any manner and / or combination falling within the scope of the appended claims, unless such features are incompatible. The applicant reserves the right to amend any originally filed claim or accordingly file any new claim, including the right to modify any originally filed claim to be subordinate to any other claim and / or incorporated into any other claim, although not initially claimed in this manner. Attached Figure Description

[0057] One or more embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:

[0058] Figure 1 A perspective view showing an example of a vehicle is displayed;

[0059] Figure 2 A schematic diagram illustrating an example of an electric vehicle is shown;

[0060] Figure 3 A schematic diagram of an example of the illustrated system is shown;

[0061] Figure 4 A schematic diagram of an example of a control system is shown;

[0062] Figure 5 A schematic diagram illustrating an example of a non-transitory computer-readable storage medium is shown;

[0063] Figure 6A A flowchart illustrating an example of a reactive overheat protection method is shown;

[0064] Figure 6B The illustration is for Figure 6A A graph showing example use cases for the method;

[0065] Figure 7A A flowchart illustrating an example of a reactive cold protection method is shown;

[0066] Figure 7B The illustration is for Figure 7A A graph showing example use cases for the method;

[0067] Figure 8A A flowchart illustrating an example of a predictive overheat protection method is shown;

[0068] Figure 8B The illustration is for Figure 8A A graph showing example use cases for the method; and

[0069] Figure 9 A flowchart illustrating an example of a thermal regulation request method is shown. Detailed Implementation

[0070] This article refers to the appendix Figure 1 Vehicle 1 according to an embodiment of the present invention is described. In some, but not all, examples, vehicle 1 is a passenger vehicle, also referred to as a passenger car or automobile. In other examples, embodiments of the invention can be implemented for other applications, such as commercial vehicles.

[0071] Figure 2 A schematic diagram of vehicle 1 is shown, wherein the vehicle is a battery electric vehicle (BEV) or a hybrid electric vehicle (HEV).

[0072] Figure 2 A vehicle 1 is shown, including a traction battery 202 or an equivalent energy storage device. The traction battery 202 is electrically connected to a DC-DC power converter 204. The DC-DC power converter 204 is electrically connected to an inverter 206 (DC-AC power converter). The inverter 206 is part of the electric drive system and is referred to herein as an electric drive unit (EDU) 208 for illustrative purposes.

[0073] EDU 208 includes a motor 210 capable of operating as a traction motor. The traction motor 210 can operate as both an electric motor and a generator. EDU 208 also includes a transmission 212 associated with the traction motor 210. In use, the traction motor 210 provides torque to one or more wheels of the vehicle 1 via the transmission 212. The traction motor 210 is associated with an inverter 206 for supplying power from the traction battery 202 to the traction motor 210. The transmission 212 provides at least one gear ratio between the output of the traction motor 210 and one or more wheels of the vehicle 1.

[0074] In some embodiments, the traction motor 210 and the transmission 212 may be integrated into a single unit or housing to provide an EDU 208 for vehicle 1. In some embodiments, the traction motor 210 and the transmission 212 are associated with an axle of vehicle 1, the axle being configured to provide torque to a first wheel and a second wheel associated with the axle, the first wheel and the second wheel being respectively located at corresponding ends of the axle. However, it should be understood that the EDU 208 may be associated with only one wheel of vehicle 1.

[0075] Figure 3 An oil circuit 310 and a coolant circuit 350 are shown, which are thermally connected together via a coolant-oil (coolant-lubricant) heat exchanger (“heat exchanger” herein) 324.

[0076] In this example, oil circuit 310 is a lubricant circuit forming part of EDU 208. The oil within oil circuit 310 both lubricates and cools EDU 208. Coolant circuit 350 is part of the vehicle 1's thermal management system, which may be a vehicle-grade coolant system, simply referred to as coolant system 340. In other examples, the fluids are not oil and coolant.

[0077] The coolant system 340 is used to exchange heat between the coolant and various modules that are thermally connected or can be connected to the coolant system 340. Figure 3 Three such modules are depicted. These modules include: a traction battery cooler 360; a climate control module 362 for a heating, ventilation and cooling system (HVAC) (e.g., a coolant-to-coolant heat exchanger); and a heat transfer module 345 for the EDU208.

[0078] The order and number of modules are outside the scope of this disclosure.

[0079] exist Figure 3 The diagram shows components for the heat transfer module 345 of the EDU 208. The heat transfer module 345 includes an inlet 352 and an outlet 358 for receiving and discharging coolant fluid flowing around the coolant loop 350 of the coolant system 340, respectively.

[0080] The heat transfer module 345 includes a coolant temperature sensor 354 located between the inlet 352 and the outlet 358. Therefore, the coolant temperature sensor 354 can locally sense the real-time coolant temperature within the heat transfer module 345. The coolant temperature sensor may alternatively or additionally be located elsewhere in the coolant system 340.

[0081] The heat transfer module 345 also includes an inverter section 356 for thermal connection to the inverter 206. Therefore, the inverter 206 can be coolant-cooled.

[0082] The coolant circuit 350 within the heat transfer module 345 flows through the heat exchanger 324. The oil circuit 310 also flows through the heat exchanger 324. The heat exchanger 324 provides a thermal bridge between the coolant circuit 350 of the coolant system 340 and the oil circuit 310 of the EDU 208. As will be described, the heat exchanger 324 can be selectively bypassed.

[0083] In this implementation, EDU 208 is entirely oil-cooled. Therefore, the heat transfer module 345 does not further include a coolant-filled sheath that circulates coolant around a portion of EDU 208 (e.g., the stator). The stator sheath can alternatively be oil-filled. This means that the temperature of EDU 208 can be managed independently of the coolant temperature by controlling whether heat exchanger 324 is bypassed. This hardware configuration implies that the thermal conditions of the EDU are strongly correlated with the oil temperature therein, where the coolant temperature is not a disturbing variable if heat exchanger 324 is bypassed. In other examples, EDU 208 may be partially and directly cooled by coolant.

[0084] It should be noted that the order of the inverter section 356, heat exchanger 324, and coolant temperature sensor 354 located between inlet 352 and outlet 358 may differ from that of the inverter section 356, heat exchanger 324, and coolant temperature sensor 354. Figure 3 The order shown is not restricted in this way.

[0085] The oil circuit 310 of the EDU 208 shown is now described. This oil circuit 310 circulates oil through both the traction motor 210 and the transmission 212.

[0086] An oil tank 312 is shown, from which oil flows via a pickup to an oil pump 314. The oil pump 314 can be controlled by a pump control signal to change the oil pressure and / or flow rate within the oil circuit 310.

[0087] Then, the oil flows through the oil filter 316 to the active bypass valve 318. The active bypass valve 318 is an electronic valve that can be controlled by a valve control signal to control whether the oil flows through the channel 322, which includes the heat exchanger 324, or through the bypass channel 320 that bypasses the heat exchanger 324.

[0088] When the oil is hotter than the coolant, the active bypass valve 318 closes, meaning the bypass passage 320 is closed and the heat exchanger passage 322 is open. The oil then flows through the heat exchanger 324 and loses its heat to the coolant. The coolant, in turn, heats up. If the active bypass valve 318 is open, meaning the bypass passage 320 is open and the heat exchanger passage 322 is closed, the oil will flow through the bypass passage and will not lose its heat to the coolant. It should be understood that the terms "closed" and "open" are non-limiting and refer only to the first and second states of the active bypass valve 318.

[0089] By extension, if the oil is colder than the coolant and the active bypass valve 318 is closed, the coolant will heat the oil via the heat exchanger 324. However, if the active bypass valve 318 is open, the coolant will not heat the oil.

[0090] The oil temperature can be detected in real time via the oil temperature sensor 326 (lubricant temperature sensor) in the oil circuit 310. The oil temperature sensor 326 may optionally be an OTP (oil temperature and pressure sensor).

[0091] By measuring and comparing the sensed real-time temperatures of the coolant and oil via sensors 354 and 326, the active bypass valve 318 can be controlled with full sensory perception of the effect it will have on the oil and coolant temperatures at a specific location.

[0092] In this example, the active bypass valve 318 is a binary valve, allowing all oil to flow through one or the other of those channels 320, 322. In other examples, the active bypass valve 318 may be controllable to provide a variable ratio of oil flow through each of the channels 320, 322.

[0093] Although in this example, the active bypass valve 318 and bypass passage 320 belong to the oil circuit 310, in other examples they may belong to the coolant circuit 350 to provide the same function by directing coolant through or around the heat exchanger 324.

[0094] Figure 3 The oil stator sleeve 328 in the oil circuit 310 is also shown to allow oil to circulate around the stator of the electric traction machine. A transmission oil sprayer 330 is also shown for spraying oil at the mechanism of the transmission 212. The oil is then conveyed back to the oil sump 312.

[0095] It should be noted that the order of oil pump 314, oil filter 316, active bypass valve 318, heat exchanger 324, oil temperature sensor 326, oil stator sleeve 328, and transmission oil sprayer 330 can be the same as... Figure 3 The order shown is different and is not restricted in this way.

[0096] Reference Figure 4 The diagram shows a control system 400 for vehicle 1. The control system 400 includes one or more controllers 401.

[0097] The control system 400 is configured to receive temperature data from multiple sources, including a coolant temperature sensor 354 and an oil temperature sensor 326, and compare the temperature data. The control system 400 can then output control signals to control the active bypass valve 318 and / or the oil pump 314.

[0098] like Figure 4 The illustrated control system 400 includes a controller 401, although it should be understood that this is merely illustrative. The controller 401 includes a processing device 404 and a memory device 406. The processing device 404 may be one or more electronic processing devices 404 operably executing computer-readable instructions. The memory device 406 may be one or more memory devices 406. The memory device 406 is electrically coupled to the processing device 404. The memory device 406 is configured to store instructions, and the processing device 404 is configured to access the memory device 406 and execute the instructions stored thereon.

[0099] Controller 401 includes an input device 410 and an output device 412. Input device 410 may include an electrical input 410 of controller 401. Output device 412 may include an electrical output 412 of controller 401. Controller 401 may have an interface 402 including electrical input / output I / O 410, 412, or electrical input 410 or electrical output 412 for receiving information and interacting with external components. Input 410 is configured to receive temperature signals from oil temperature sensor 326 and coolant temperature sensor 354, as well as one or more other internal or external controllers 327. The temperature signals are electrical signals indicating the absolute temperatures of the oil and coolant, respectively. Output 412 is configured to output a valve control signal to active bypass valve 318 and / or a pump control signal to oil pump 314, indicating a request to control the state of active bypass valve 318 and / or the flow rate of oil pump 314.

[0100] Figure 3 and Figure 4 Together shown is a system 300 including a control system 400 and an EDU 208. An active bypass valve 318 for the oil circuit 310 of the EDU 208 can be controlled by a valve control signal from the control system 400 to control the flow rate through the heat exchanger 324 relative to the flow rate through the bypass passage 320.

[0101] Figure 5A non-transitory computer-readable storage medium 500 including instructions (computer software) is shown.

[0102] Figure 6A A method 600 according to an embodiment of the present invention is shown. Method 600 is a method for controlling the temperature of an EDU 208 in a vehicle 1. In particular, method 600 is a method for providing reactive overheat protection for the EDU 208. Method 600 can be achieved by... Figure 4 The control system 400 or system 300 shown is used to execute this. In particular, the memory 406 may include computer-readable instructions 408, which, when executed by the processor 404, perform method 600.

[0103] In summary, method 600 includes: determining whether reactive overheat protection for EDU 208 is required, indicating that the absolute oil temperature measured by oil temperature sensor 326 is greater than a threshold. If reactive overheat protection for EDU 208 is required, the oil temperature is compared with the coolant temperature. If the oil temperature is greater than the coolant temperature, guiding the oil through heat exchanger 324 will help reduce the oil temperature. If the oil temperature is less than the coolant temperature, bypassing heat exchanger 324 will prevent the oil from being further heated. Therefore, the control signal sent to active bypass valve 318 depends not only on the requirement for reactive overheat protection but also on the temperature comparison.

[0104] The advantage lies in improved thermal protection, because when thermal protection of EDU 208 is identified, the control system 400 compares the temperatures on both sides of the heat exchanger 324 to determine whether to guide or inhibit oil through the heat exchanger 324, which will be more effective in protecting EDU 208.

[0105] Box 602 indicates the start of method 600.

[0106] At block 604, method 600 includes determining the current state of the active bypass valve 318 as a subcondition. If the active bypass valve 318 is currently in a state where oil flow is directed through bypass channel 320, the flowchart proceeds along a first path (blocks 604, 606, 610, 613, 614, 616) including block 606. If the active bypass valve 318 is in another state where oil flow is directed through channel 322 including heat exchanger 324, the flowchart proceeds along a second path (blocks 604, 608, 610, 613, 614, 616) including block 608. These two paths enable the use of a hysteresis control strategy, which will be described in detail after the first path.

[0107] For example, the current state of the active bypass valve 318 can be determined at block 604 by querying a stored flag or querying a valve status sensor.

[0108] At box 606, method 600 includes determining whether reactive overheat protection for EDU 208 is required based on a signal indicating the temperature of EDU 208 received at input box 605 (e.g., the absolute oil temperature of EDU 208 originating from oil temperature sensor 326). Later in the flowchart, if the coolant is colder than the oil, this causes a change in the state of active bypass valve 318, thereby deselecting bypass passage 320 and instead directing fluid flow through heat exchanger 324 to cool EDU 208.

[0109] Block 606 includes determining whether a reactive overheat protection condition is met, which is configured to identify the type of thermal protection condition for current overheating of EDU 208. In an implementation, the reactive overheat protection condition includes a first overheat temperature threshold. If the oil temperature is greater than the threshold and also greater than the coolant temperature (as determined in subsequent decision block 613), the first overheat temperature threshold can be described as a threshold that changes the state of the active bypass valve 318 to direct oil flow through the heat exchanger 324.

[0110] The first overheating temperature threshold can be a value exceeding 100 degrees Celsius, for example, a range from 130 to 160 degrees Celsius. This is below a separate derating threshold of the control system 400, which, if exceeded, may cause the control system 400 to drate the EDU 208 by limiting its power output. The difference between the first overheating temperature threshold and the derating threshold can be greater than 10 degrees Celsius.

[0111] In the example above, the conditions (box 606) are based on absolute oil temperature, meaning the conditions depend primarily or entirely on the oil temperature of EDU 208. Since EDU 208 is fully or substantially oil-cooled, the oil temperature is closely related to the EDU temperature. Therefore, although the difference between oil temperature and coolant temperature is considered in the next box 613, the coolant temperature, or the difference between coolant temperature and oil temperature, may not be the determining factor for the need for overheat protection for EDU 208.

[0112] If the oil temperature is below the first superheat temperature threshold, the flowchart proceeds to block 610 (no request position), which maintains the current state of the active bypass valve 318 (and modifies it through other different control methods 700, 800, and 900). Block 610 can then be terminated. Figure 6A Method 600. Then, control system 400 can proceed to... Figure 7A , Figure 8A or Figure 9 Methods 700, 800, or 900.

[0113] However, if the oil temperature requiring overheat protection exceeds the first overheat temperature threshold, then a specific position of the bypass valve 318 is requested based on the result of subsequent decision block 613.

[0114] At box 613, method 600 includes comparing a first signal received at input boxes 611 and 612 with a second signal. The first signal indicates the temperature of EDU 208 of vehicle 1 and refers to a signal of the same type as that at input box 605, such as the oil temperature of EDU 208 originating from oil temperature sensor 326. The second signal indicates the temperature of coolant system 340 of vehicle 1, such as the coolant temperature of coolant system 340 originating from coolant temperature sensor 354. Therefore, box 613 compares the temperature of EDU 208 with the temperature of coolant system 340.

[0115] If the first signal indicates oil temperature and the second signal indicates coolant temperature, the comparison is made between the oil temperature and the coolant temperature. Since the sensor is located locally on heat exchanger 324, the comparison indicates the temperature on each side of heat exchanger 324, and therefore indicates in which direction heat energy will be transferred through heat exchanger 324. Advantageously, control system 400 can determine whether to guide or inhibit the flow of oil through heat exchanger 324.

[0116] This comparison can include a responsiveness comparison based on a first signal and a second signal. The signal can indicate the temperature sensed in real time.

[0117] A control signal is output from block 614 or block 616. If the first signal is greater than the second signal (oil temperature greater than coolant temperature), the flowchart proceeds to block 616, which includes configuring the control signal to control the heat exchange between EDU 208 and the coolant system 340 by requesting the active bypass valve 318 to flow through channel 322, which includes heat exchanger 324, instead of bypass channel 320. This triggers reactive thermal protection for EDU 208, as the heat from the oil is transferred to the cooler coolant, thereby cooling EDU 208. This advantageously reduces the likelihood of EDU 208 reaching its derating temperature.

[0118] However, based on the first signal being less than the second signal (oil temperature less than coolant temperature), the flowchart proceeds to block 614, which configures the control signal to control the heat exchange between EDU 208 and coolant system 340 by requesting the active bypass valve 318 to be in the following state: bypassing heat exchanger 324 by directing oil flow through bypass channel 320 instead of channel 322, which includes heat exchanger 324. Since the active bypass valve 318 is already in this state, the control signal effectively requests that this state be maintained.

[0119] In summary, the flowchart will change the state of the active bypass valve 318 from a state where the heat exchanger 324 is bypassed to a state where oil flows through the heat exchanger 324 to cool the EDU 208, unless the coolant is hotter than the oil, in which case the heat exchanger 324 will remain bypassed.

[0120] The requested state of the active bypass valve 318, requested by box 614 or box 616, is maintained (locked) until a subsequent iteration of method 600 detects that the EDU temperature has returned to normal. In other words, the requested state is maintained until a subsequent iteration proceeds to box 610 (no request position). Figure 6A Method 600 can be repeated continuously during the driving cycle of vehicle 1.

[0121] When implemented, method 600 may optionally include additional measures, such as activating a coolant refrigeration system or coolant radiator branch to further reduce the temperature of the coolant, and thus reduce the temperature of the oil.

[0122] The advantage of using a control signal based on comparison rather than solely on the absolute temperature of the EDU 208 is that a wide variety of thermal management scenarios can be considered, especially during driving cycles when coolant and oil temperatures may begin to deviate significantly from each other, for example, when the oil may heat up faster than the coolant.

[0123] The above example relates to a valve control signal, which has the advantage that the active bypass valve 318 is controlled, allowing the oil pump 314 to be independently controlled to maintain the desired oil pressure and flow rate. However, it should be understood that blocks 614 and 616 can also output a pump control signal, either in place of or in addition to the valve control signal. According to the comparison in block 613, the pump control signal can control the oil pump 314 to increase or decrease the oil flow through the heat exchanger 324. For example, when the coolant is colder than the oil, the oil flow rate can be increased at block 616. When the coolant is hotter than the oil, the oil flow rate can be decreased at block 614. Therefore, the pump control signal provides the same technical effect as the valve control signal, but requires changing the operating point of the oil pump 314.

[0124] Now returning to the initial decision box 604, which determines the current state of the active bypass valve 318, we now describe the second path of the flowchart (604, 608, 610, 613, 614, 616), the difference being that decision box 608 is executed instead of box 606. This different path defines the hysteresis control strategy as described now.

[0125] If block 604 determines that the active bypass valve 318 is currently in a state of guiding oil flow through bypass channel 320, then the first path is followed; otherwise, if block 604 determines that the active bypass valve 318 is currently in a state of guiding oil flow through channel 322, which includes heat exchanger 324, then the second path is followed.

[0126] At box 608, method 600 includes determining whether reactive overheat protection for EDU 208 is required based on a signal indicating the temperature of EDU 208 received at input box 607. Input box 607 refers to a signal of the same type as input box 605, such as the absolute oil temperature of EDU 208 originating from oil temperature sensor 326.

[0127] The reactive overheat protection condition defined by block 608 includes a second overheat temperature threshold that is less than the first overheat temperature threshold. This can be described as a threshold used to change the state of the active bypass valve 318 to direct oil flow through the bypass passage 320 when the oil temperature is greater than the second threshold and the coolant temperature is higher than the oil temperature as determined in subsequent decision block 613.

[0128] The second superheat temperature threshold can be a value exceeding 100 degrees Celsius and less than the first superheat temperature threshold to define the hysteresis gap.

[0129] By having a second superheat temperature threshold for bypassing heat exchanger 324 that is lower than the first superheat temperature threshold used for connecting heat exchanger 324, heat exchanger 324 can remain connected until the temperature of EDU 208 is significantly reduced. The advantage is that it defines a hysteresis control strategy; the difference between the thresholds defines the hysteresis gap. This is useful in the example where the active bypass valve 318 is binary (i.e., method 600 is a bang-bang control method) because it prevents excessive valve state switching, also known as jitter.

[0130] If the second overheating temperature threshold is exceeded at box 608, the flowchart proceeds to box 613, which operates as previously described. In other words, if the oil temperature is greater than the coolant temperature, box 616 is selected, which requests the active bypass valve 318 to be in a state where oil flow is directed through channel 322, which includes heat exchanger 324, instead of bypass channel 320. Since the active bypass valve 318 is already in this state, the valve control signal effectively requests that this state be maintained. However, if the oil temperature is less than the coolant temperature, box 614 is selected, which requests the active bypass valve 318 to be in a state where oil is directed through bypass channel 320. This changes the state of the active bypass valve 318, deselecting the current state in which heat exchanger 324 is used.

[0131] Figure 6B It is used for depiction Figure 6AA pair of graphs for example use cases of the reactive overheat protection method 600.

[0132] The graph above depicts the oil temperature "OT" of EDU 208 and the coolant temperature "CT" of coolant system 340. The y-axis represents temperature "T", and the x-axis represents time "t". A first overheating temperature threshold is at level 606, and a second overheating temperature threshold is at level 608, to which the oil temperature OT is compared. They are separated by a hysteresis gap. The thresholds are represented by dashed lines, which become thick solid lines when the threshold is active (i.e., the threshold to which the control system 400 is currently comparing the oil temperature).

[0133] The graph below depicts the requested valve state "VS" of the active bypass valve 318. The y-axis represents the percentage of flow through the heat exchanger 324, which in this example is either 0% or 100% because the active bypass valve 318 is binary. 0% indicates a "bypass open - heat exchanger (HEX) inactive" state, where the guide oil flow is through the bypass passage 320, and 100% indicates a "bypass closed - HEX active" state, where the guide oil flow is through the passage 322 including the heat exchanger 324 (HEX). The requested valve state VS is a dashed line when the valve state is not requested (box 610) and becomes a thick solid line when a particular valve state is requested (boxes 614, 616).

[0134] At time t0, the active bypass valve 318 is determined to be in the bypass open - HEX inactive state (box 604). Therefore, the relevant threshold is the first superheat temperature threshold 606. Since the oil temperature OT is less than the threshold, there is no requested valve position (box 610).

[0135] At time t1, the oil temperature OT exceeds the first overheating temperature threshold 606. In response, the oil temperature OT is compared with the coolant temperature CT (box 613). Since the coolant temperature CT is colder than the oil temperature OT, the control system 400 requests the bypass shutdown-HEX active state (box 616). After time t1, the oil temperature OT reaches its peak and begins to decline.

[0136] Between time t1 and time t3, the active bypass valve 318 is determined to be in the bypass-closed-HEX active state (box 604). Therefore, starting from time t1, the relevant threshold is now the second superheat temperature threshold 608. Since the oil temperature OT is greater than the second superheat temperature threshold 608 and higher than the coolant temperature CT (box 613), the control system 400 maintains the request for the bypass-closed-HEX active state (box 616). It is not important that the oil temperature drops below the first superheat temperature threshold 606 at time t2, because this is not the currently selected threshold.

[0137] At time t3, the oil temperature OT drops below the coolant temperature CT. Even if the oil temperature OT is still hot (hotter than the second overheating temperature threshold 608), the control system 400 requests the bypass activating - HEX inactive state to prevent the coolant from causing the oil to heat up.

[0138] After time t3, at the next loop of method 600, the active bypass valve 318 is determined to be in the bypass open - HEX inactive state (box 604). Therefore, the relevant threshold has now returned to the first superheat temperature threshold 606. Since the oil temperature OT is less than the first superheat temperature threshold 606, there is no requested valve position (box 610) even though the oil temperature remains above the (now inactive) second threshold temperature 608 for at least a period of time after t3.

[0139] Figure 7A A method 700 according to an embodiment of the present invention is shown. Method 700 is a method for controlling the temperature of an EDU 208 in a vehicle 1. In particular, method 700 is a method for providing reactive cold protection for the EDU 208. When the EDU 208 is cold, its efficiency is adversely affected by factors such as lubricant viscosity and winding temperature. Method 700 can be... Figure 4 The control system 400 or system 300 shown in the diagram executes the method 700. In particular, the memory 406 may include computer-readable instructions 408, which, when executed by the processor 404, perform the method 700.

[0140] Optionally, Figure 7A Method 700 can be used with Figure 6A The method is the same as 600, but its advantage is that the EDU 208 temperature can be controlled under both hot and cold (e.g., freezing) conditions.

[0141] Figure 7A Flowcharts and Figure 6A The flowchart is structured similarly. For the sake of brevity, only the differences will be described in detail, not the similarities.

[0142] Box 702 is the start box. If in... Figure 6A Method 600 is executed after Figure 7A If method 700 is executed, then box 610 (no requested position) can trigger the start box 702 of method 700. Alternatively, they can be executed in reverse order, where box 710 (described further below) triggers the start box 602 of method 600.

[0143] Box 704 is the same as box 604, for determining subconditions including the current state of the active bypass valve 318.

[0144] Regarding boxes 705, 706, and 710, the descriptions of boxes 605, 606, and 610 apply, except that box 706 defines reactive cold protection conditions, rather than reactive overheat protection conditions, for determining whether reactive cold protection of EDU 208 is required. Therefore, the condition in box 706 defines a first cold temperature threshold. The first cold temperature threshold can be a value below zero degrees Celsius or below -20 degrees Celsius, for example, approximately -25 degrees Celsius.

[0145] If the absolute oil temperature of EDU 208 is lower than the first cold temperature threshold, then box 706 is satisfied and the flowchart proceeds to box 713. If the absolute oil temperature is higher than the first cold temperature threshold, then box 706 is not satisfied and the flowchart proceeds to box 710 (no request position, equivalent to box 610).

[0146] The descriptions of boxes 711, 712, and 713 apply to boxes 611, 612, and 613. That is, the oil temperature is compared with the coolant temperature. A control signal is output at box 714 or box 716. If the oil temperature is lower than the coolant temperature, the control signal at box 716 is configured to request the active bypass valve 318 to flow through channel 322, which includes heat exchanger 324, instead of bypass channel 320, so that the warmer coolant can heat the oil. However, if the oil temperature is higher than the coolant temperature, the control signal at box 714 is configured to request the active bypass valve 318 to flow through bypass channel 320 instead of channel 322, which includes heat exchanger 324, to prevent the colder coolant from further cooling the oil.

[0147] The advantage is that the heat exchanger 324 will only be used if the heat exchanger 324 is able to make the EDU 208 heat up.

[0148] Figure 7A Method 700 also includes a second path via box 708 instead of box 706. The different path defines the hysteresis control strategy, wherein the threshold for comparing the oil temperature depends on the current state of the active bypass valve 318.

[0149] Regarding box 708, the description of box 608 applies except that box 708 defines the second cold temperature threshold. The second cold temperature threshold can be a value below zero degrees Celsius, such as approximately -20 degrees Celsius, which is higher than the first cold temperature threshold, creating a hysteresis gap between the first and second cold temperature thresholds.

[0150] Therefore, if the absolute oil temperature of EDU 208 is lower than the second cold temperature threshold, then box 708 is satisfied and the flowchart proceeds to box 713. If the absolute oil temperature is higher than the second cold temperature threshold, then box 708 is not satisfied and the flowchart proceeds to box 710 (no-request position, equivalent to box 610), because reactive cold protection is not required.

[0151] Advantageously, this allows the oil temperature to be heated to substantially higher than the first cold temperature threshold before the heat exchanger 324 is bypassed again.

[0152] Figure 7B It is used for depiction Figure 7A A pair of graphs for an example use case of the cold protection method 700. Except that the thresholds are a first cold temperature threshold "706" and a second cold temperature threshold "708", the format of the graphs is the same as... Figure 6B same.

[0153] At time t4, the active bypass valve 318 is determined to be in the bypass open - HEX inactive state (box 704). Therefore, the relevant threshold is the first cold temperature threshold 706. Since the oil temperature OT is higher than the threshold, there is no requested valve position (box 710).

[0154] At time t5, the oil temperature OT becomes lower than the first cold temperature threshold 706. In response, the oil temperature OT is compared with the coolant temperature CT (box 713). Since the depicted coolant temperature CT is higher than the oil temperature OT, the control system 400 requests the bypass shutdown-HEX active state (box 716). After time t5, the oil temperature OT begins to rise.

[0155] Between time t5 and time t6, the active bypass valve 318 is determined to be in the bypass closed-HEX active state (box 704). Therefore, the relevant threshold is now the second cold temperature threshold 708. Since the oil temperature OT is lower than the second cold temperature threshold 708 and lower than the coolant temperature CT (box 713), the control system 400 maintains the request for the bypass closed-HEX active state (box 716).

[0156] At time t6, the oil temperature OT rises above the second cold temperature threshold 708. Therefore, there is no request valve position (box 710) because reactive cold protection is no longer needed.

[0157] Figure 8A A method 800 according to an embodiment of the present invention is shown. Method 800 is a method for controlling the temperature of an EDU 208 in vehicle 1. Specifically, method 800 is a method for providing predictive overheat protection for the EDU 208. Method 800 can be... Figure 4The control system 400 or system 300 shown in the diagram executes the method 800. In particular, the memory 406 may include computer-readable instructions 408, which, when executed by the processor 404, perform the method 800.

[0158] Optionally, Figure 8A Method 800 can be like Figure 6A and Figure 7A It can be performed in the manner of one or both of methods 600 and 700, with the advantage that the EDU temperature can be preemptively controlled to further reduce the chance of derating the EDU 208.

[0159] Box 802 is the start box. If in... Figure 6A or Figure 7A Execute after method 600 and method 700 Figure 8A If method 800 is executed, then box 610 or box 710 (no requested position) can trigger the start box 802 of method 800. Alternatively, they can be executed in reverse order, where box 810 (described further below) is a trigger for either method 600 or method 700.

[0160] At box 806, method 800 determines sub-conditions that satisfy the predictive overheat protection condition to determine the need for predictive thermal protection of EDU 208. This determination depends on a signal received at input box 805 indicating a requested operating point of EDU 208. This signal may indicate a requested load of EDU 208, such as a power request (kW or equivalent unit). The signal may originate from an internal or external controller 327 used to control the operating point of EDU 208. The signal may be a feedforward signal or a feedback signal.

[0161] Since the temperature of EDU 208 increases with its operating point, with a delay in between, a rapid and significant increase in the requested operating point will cause the EDU temperature to quickly reach the derating threshold and / or trigger [a certain condition]. Figure 6A A suitable predictor for reactive overheat protection.

[0162] Predictive overheat protection conditions may include an operating point threshold, based on the operating point exceeding the threshold to satisfy the condition. The operating point threshold may be a value greater than 30 kW, greater than 60 kW, or greater than 90 kW. Under normalized conditions, the threshold may be greater than 30%, 60%, or 80% of the maximum requestable operating point of EDU 208.

[0163] Since the operation point is less than the operation point threshold, the flowchart proceeds to box 810 (no request position). Box 810 allows the current state of the active bypass valve 318 to be maintained. Box 810 can be terminated. Figure 8AMethod 800. Then, the control system 400 can proceed to another method according to the order / priority of the methods, for example... Figure 9 Method 900 or the methods 600 and 700 described above.

[0164] The descriptions of blocks 811, 812, and 813 apply to blocks 611, 612, and 613. That is, the oil temperature is compared with the coolant temperature. A control signal is output at block 814 or block 816. If the oil temperature is greater than the coolant temperature, the control signal at block 816 is configured to request the active bypass valve 318 to direct oil flow through channel 322, which includes heat exchanger 324, instead of bypass channel 320, so that the cooler coolant can cool the oil. However, if the oil temperature is less than the coolant temperature, the control signal at block 814 is configured to request the active bypass valve 318 to direct oil flow through bypass channel 320 instead of channel 322, which includes heat exchanger 324, to prevent the hotter coolant from heating the oil. Blocks 814 and 816 are executed before the absolute oil temperature exceeds the relevant thresholds 606, 608, or the derating threshold.

[0165] The advantage is that the heat exchanger 324 can be used only when the heat exchanger 324 can anticipate the expected temperature rise of the EDU at the requested operating point and preemptively cool the EDU 208.

[0166] Figure 8B The depiction uses Figure 8A Three graphs illustrating example use cases of the predictive overheat protection method 800. The middle and bottom graphs have the same characteristics as... Figure 6B and Figure 7B Same format. The top graph depicts the operation point "OP" (solid line) of EDU 208 relative to the operation point threshold of 806 (dotted line).

[0167] At time t7, the operation point OP of EDU 208 is less than the operation point threshold 806. Therefore, there is no request valve position (box 810).

[0168] At time t8, the operating point OP of EDU 208 exceeds the operating point threshold 806. In response, the oil temperature OT is compared with the coolant temperature CT (box 813). Since the depicted oil temperature OT is higher than the coolant temperature CT, the control system 400 requests the bypass shutdown-HEX active state (box 816) to allow the coolant to cool the oil. After time t8, the oil temperature OT reaches its peak and begins to decline.

[0169] At time t9, for example, due to a rise in coolant temperature, the oil temperature OT drops below the coolant temperature CT. However, the operating point OP still exceeds the operating point threshold 806. Nevertheless, the control system 400 requests the bypass activating - HEX inactive state (box 814) to prevent the now hotter coolant from causing the oil to heat up.

[0170] At time t10, the operating point OP drops below the operating point threshold 806 or another lower hysteresis threshold. Therefore, there is no requested valve position (box 810) because preheating protection is not required.

[0171] Figure 9 A method 900 according to an embodiment of the present invention is shown. Method 900 is a method for controlling the temperature of EDU 208 of vehicle 1. In particular, method 900 is a method for controlling an active bypass valve 318 based on a thermal regulation request. Method 900 can be... Figure 4 The control system 400 or system 300 shown in the diagram executes the method 900. In particular, the memory 406 may include computer-readable instructions 408, which, when executed by the processor 404, perform the method 900.

[0172] Thermal regulation refers to heating or cooling one of the coolant system 340 or modules 208, 360, and 362 thermally connected to the coolant system 340 for thermal regulation purposes. The purpose of thermal regulation may be energy optimization or comfort, and is unrelated to thermal protection such as overheating or overcooling.

[0173] Thermal regulation requests can be determined using energy efficiency algorithms. These algorithms can be vehicle-level energy efficiency algorithms, which consider the overall vehicle energy consumption as a variable.

[0174] For example, thermal regulation during a driving cycle may include using EDU 208 as a heat source to heat the coolant to supply additional heat to the climate control module 362. This can help warm the passenger compartment.

[0175] Thermal conditioning may also be required outside of driving cycles. A specific example of thermal conditioning is pre- or post-conditioning the oil in EDU 208 before or after a driving cycle. For instance, if vehicle 1 is connected to a charger and the traction battery 202 has reached a suitable state of charge, an electric heater, cooling system, or coolant radiator branch can heat or cool the coolant to supply heat to or remove heat from EDU 208 or other modules. Pre-conditioning EDU 208 can serve as a preheater (or precooler) for EDU 208 to improve its efficiency.

[0176] Optionally, Figure 9 Method 900 can be like Figures 6A to 8AIt can be executed as in one or more of methods 600, 700, and 800, wherein it has a lower priority than the methods mentioned above. This has the advantage that, if thermal protection is not required, the active bypass valve 318 can be used to optimize the controller for thermal regulation purposes.

[0177] Box 902 is the start box. If... Figure 9 Method 900 in Figure 6A , Figure 7A or Figure 8A If methods 600, 700, and 800 are executed after these methods, then box 610, box 710, or box 810 (without a requested position) can trigger the start box 902 of method 900. This means... Figure 9 Method 900 is a lower / lower priority method than the aforementioned methods, and only when the aforementioned higher priority thermal protection methods enable the current state of the active bypass valve 318 to be, for example... Figure 9 Method 900 can only be executed if other lower priority control methods are modified (i.e., in a state without a request).

[0178] At box 904, method 900 includes: determining whether thermal adjustment has been requested based on a signal indicating a thermal adjustment request received at input box 905.

[0179] In a non-limiting example, the signal might require a specific state of the active bypass valve 318, originating from an external controller 327 of the vehicle 1, such as the vehicle system controller (VSC). The VSC may host an energy efficiency algorithm configured to determine the thermal regulation requirements of the module, causing the VSC to output a signal to the control system 400 requesting a specific state of the active bypass valve 318. It should be understood that the determination can be made within the control system 400, where the energy efficiency algorithm is hosted by the control system 400, or where the control system 400 includes the VSC.

[0180] Based on the bypass closed-HEX active state of the active bypass valve 318 which has not yet been requested by the thermal regulation request (block 904), method 900 proceeds to block 914, which includes another state of the active bypass valve 318 (bypass open-HEX inactive) that requests to guide oil flow through the bypass passage 320.

[0181] For example, if no thermal adjustment request is received, or if a thermal adjustment request for the valve state has been received, the valve position can be requested.

[0182] Based on the bypass-closed-HEX active state of the active bypass valve 318 requested by the thermal regulation request (block 904), method 900 proceeds to block 906, block 906 outputs a pump control signal to the oil pump 314 to request a target oil flow rate or a minimum oil flow rate, and then proceeds to block 916, in which a valve control signal is output to request the bypass-closed-HEX active state of the active bypass valve 318 to guide the oil flow through the heat exchanger 324.

[0183] The pump control signal advantageously allows heat to circulate within EDU 208 even when there is no oil flow normally, even outside the driving cycle of vehicle 1. In other examples, oil pump 314 may already be running, and its flow rate may not vary as part of method 900.

[0184] The target oil flow rate or minimum oil flow rate can be a default value, or it can depend on the information included in the thermal regulation request.

[0185] Although not shown, the specific request state of the active bypass valve 318 can depend on the comparison between the oil temperature and the coolant temperature to determine whether the EDU 208 will be used as a heat source for the coolant or as a radiator if the heat exchanger 324 is connected.

[0186] In the example implementation:

[0187] - If the thermal regulation request in block 904 is for heating the climate control module 362, the control signal can induce thermal regulation by changing the state of the active bypass valve 318 to select the heat exchanger 324 so that heat can be transferred from EDU 208 to the coolant system 340. Alternatively, if the oil is colder than the coolant, the bypass channel 320 can be selected to inhibit heat transfer from the coolant system 340 to the EDU 208.

[0188] - If the thermal regulation request in block 904 is for cooling the climate control module 362, the control signal can induce thermal regulation by changing the state of the active bypass valve 318 to select the heat exchanger 324 so that heat can be transferred from the coolant system 340 to the EDU 208. Alternatively, if the oil is hotter than the coolant, the bypass channel 320 can be selected to inhibit heat transfer from the EDU 208 to the coolant system 340.

[0189] - If the thermal regulation request is for heating EDU 208 (e.g., pre- or post-conditioning of the oil), the control signal can induce thermal regulation by changing the state of the active bypass valve 318 to select heat exchanger 324 to cause heat transfer from coolant system 340 to EDU 208. Alternatively, if the oil is hotter than the coolant, the bypass channel 320 can be selected to suppress heat transfer from EDU 208 to coolant system 340.

[0190] In the example, method 900 is executed in a loop for minimizing vehicle-level energy consumption. The energy efficiency algorithm controls via thermal regulation requests: a) the direction of heat transfer; and b) the amount of heat transfer (e.g., the duration of actuation of the active bypass valve 318). This request may be able to request 0 (zero) transfer to achieve optimal EDU efficiency in the cold region.

[0191] To summarize the foregoing description, Figure 6A , Figure 7A and Figure 8A The common aspects of methods 600, 700, and 800 include:

[0192] Receive the first signals 605, 705, and 805 indicating the temperature of EDU 208 of vehicle 1;

[0193] Receive second signals 611, 711, and 811 indicating the temperature of the coolant system 340 of vehicle 1;

[0194] Compare the first and second signals of 613, 713, and 813; and

[0195] Output control signals 614, 616, 714, 716, 814, 816 to control the heat exchange between EDU 208 and coolant system 340, wherein the control signals depend on the comparison.

[0196] The preceding description demonstrates the advantage of the control signal being based on a comparison of the system's temperature rather than on the absolute temperature of EDU 208. Various thermal management scenarios can be considered during a driving cycle (journey), as temperatures will deviate from each other during the driving cycle. The control system 400 can determine whether to guide (start or significantly increase) or inhibit (stop or significantly reduce) the fluid flow through heat exchanger 324. If one system in the system requires additional thermal energy, and the other system is hotter, flow can be guided through heat exchanger 324 to operate the hotter system as a heat source. However, if the other system is colder, flow through heat exchanger 324 can be inhibited. Similarly, if one system in the system needs to remove thermal energy, and the other system is colder, flow can be guided through heat exchanger 324 to use the colder system as a radiator. However, if the other system is hotter, flow through heat exchanger 324 can be inhibited.

[0197] The above description Figure 7A The settings independently provide a method 700 for providing cold protection for the EDU 208 in the following manner:

[0198] Receive a first signal indicating the temperature of EDU 208 of vehicle 1; and

[0199] Based on a first signal indicating that the temperature is below a threshold, a control signal is output to suppress heat exchange between the EDU 208 of vehicle 1 and the coolant system 340.

[0200] Similarly, the above description Figure 8A The settings independently provide a method 800 for providing predictive overheat protection for EDU 208 in the following manner:

[0201] Receive the first signal indicating the request operation point for EDU 208; and

[0202] Based on the first signal, a control signal is output to control the heat exchange between the EDU 208 of vehicle 1 and the coolant system 340.

[0203] It should be understood that controller 401 or each controller 401 may include control units or computing devices having one or more electronic processors (e.g., microprocessors, microcontrollers, application-specific integrated circuits (ASICs), etc.), and may include a single control unit or computing device, or alternatively, different functions of controller 401 or each controller 401 may be embodied in or hosted in different control units or computing devices. As used herein, the terms “controller,” “control unit,” or “computing device” will be understood to include a single controller, control unit, or computing device, as well as multiple controllers, control units, or computing devices that operate together to provide the desired control functions. An instruction set may be provided that, when executed, causes controller 401 to implement some or all of the control techniques described herein (including some or all of the functions required by methods 600, 700, 800, and 900 described herein). Instruction set 408 may be embedded in the one or more electronic processors 404 of controller 401; or alternatively, instruction set 408 may be provided as software to be executed in controller 401. The first controller or control unit may be implemented as software running on one or more processors. One or more additional controllers or control units can be implemented using software running on one or more processors, optionally the same processors as the first controller or control unit. Other settings are also useful.

[0204] Electronic processor 404, or each electronic processor 404, may include any suitable electronic processor (e.g., microprocessor, microcontroller, ASIC, etc.) configured to execute electronic instructions 408. Electronic memory device 406, or each electronic memory device 406, may include any suitable memory device and may store various data, information, thresholds, lookup tables, or other data structures and / or instructions therein or on it. In embodiments, memory device 406 has information and instructions stored therein or on it for software, firmware, programs, algorithms, scripts, applications, etc., which may control all or part of the methods described herein. Processor or each electronic processor 404 may access memory device 406 and execute and / or use the instructions and information, or those instructions and information, to perform or carry out some or all of the functions and methods described herein.

[0205] At least one memory device 406 may include a computer-readable storage medium (e.g., a non-transitory or non-transient storage medium) that may include any mechanism for storing information in a form readable by a machine or electronic processor / computing device. Examples of such forms include, but are not limited to: magnetic storage media (e.g., floppy disks); optical storage media (e.g., CD-ROMs); magneto-optical storage media; read-only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROMs and EEPROMs); flash memory; or electrical or other types of media for storing such information / instructions.

[0206] It will be understood that embodiments of the present invention can be implemented in any suitable form, in hardware, in software, or in a combination of hardware and software. For example, it is contemplated that the invention is not limited to implementation by a programmable processing device, and that at least some, and in some embodiments all, of the functions and / or method steps of the invention can be equivalently implemented by non-programmable hardware, such as a non-programmable ASIC, a Boolean logic circuit system, etc. It will be understood that various changes and modifications can be made to the invention without departing from the scope of this application. Figure 6A , Figure 7A , Figure 8A , Figure 9 The boxes shown may represent steps in the method and / or code portions in computer program 408. The description of a particular order of boxes does not necessarily imply a desired or preferred order for the boxes, and the order and arrangement of the boxes can vary. Furthermore, some steps may be omitted.

[0207] The features described in the foregoing description may be used in combinations other than those explicitly described. Although functionality has been described with reference to certain features, those functions may also be performed by other features, whether or not they have been described. Although features have been described with reference to certain embodiments, those features may also exist in other embodiments, whether or not they have been described.

Claims

1. A control system for controlling the temperature of an electric drive system of a vehicle, the control system comprising one or more processors, said one or more processors being configured to: Receive a first signal indicating the temperature of the electric drive system of the vehicle; Receive a second signal indicating the temperature of the vehicle's thermal management system; Compare the first signal with the second signal; and Output control signals to control the heat exchange between the electric drive system and the thermal management system, wherein, The control signal depends on the comparison.

2. The control system according to claim 1, wherein, The control signals include valve control signals and / or pump control signals to control the fluid flow through a heat exchanger used to exchange heat energy between the electric drive system and the thermal management system.

3. The control system according to claim 1 or 2, wherein, The first signal indicates the lubricant temperature of the electric drive system, and the second signal indicates the coolant temperature of the thermal management system.

4. The control system according to claim 1, 2, or 3, wherein the control system is configured to determine whether a thermal protection condition for regulating the temperature of the electric drive system is triggered, wherein, The control signal depends on whether the thermal protection condition is triggered.

5. The control system according to claim 4, wherein, Whether to output additional control signals to control the heat exchange based on the heat regulation request depends on whether the heat protection condition is triggered.

6. The control system according to claim 4 or 5, wherein, The control signal depends on which of the multiple sub-conditions satisfying the thermal protection condition, and also on whether the comparison indicates that the temperature of the electric drive system is higher or lower than the temperature of the thermal management system.

7. The control system according to claim 4, 5 or 6, wherein, The thermal protection conditions include thresholds that are set to limit the hysteresis control strategy.

8. The control system according to any one of claims 4 to 7, wherein, The thermal protection conditions include overheat protection conditions for detecting and / or predicting overheating of the electric drive system.

9. The control system according to claim 8, wherein, The overheat protection conditions include reactive overheat protection conditions that depend on the temperature of the electric drive system.

10. The control system according to claim 8 or 9, wherein, The overheat protection conditions include predictive overheat protection conditions that depend on signals indicating the operating point of the electric drive system.

11. The control system according to any one of claims 4 to 10, wherein, The thermal protection conditions include cold protection conditions that depend on the temperature of the electric drive system.

12. A system comprising a control system according to any one of the preceding claims and the electric drive system, wherein, The electric drive system includes a lubricant circuit, a coolant-lubricant heat exchanger thermally connected to the lubricant circuit, a bypass passage bypassing the coolant-lubricant heat exchanger, and an active bypass valve that can be controlled by the control signal according to the comparison to control the fluid flow through the coolant-lubricant heat exchanger relative to the fluid flow through the bypass passage.

13. A vehicle comprising a control system according to any one of the preceding claims or a system according to claim 12.

14. A method for controlling the temperature of an electric drive system of a vehicle, the method comprising: Receive a first signal indicating the temperature of the electric drive system of the vehicle; Receive a second signal indicating the temperature of the vehicle's thermal management system; Compare the first signal with the second signal; as well as An output control signal is provided to control the heat exchange between the electric drive system and the thermal management system, wherein the control signal depends on the comparison.

15. A computer-readable instruction, which, when executed by a computer, is configured to perform the method according to claim 14.

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