Control method, electric drive thermal management system and vehicle

Abstract

The application provides a control method, an electric drive heat management system and a vehicle. The control method comprises the following steps: selecting a heat management operation mode of the electric drive heat management system based on a vehicle working condition, the heat management operation mode comprising a rapid cooling mode, the rapid cooling mode comprising a battery and electric drive double rapid cooling mode, wherein the electric drive heat management system comprises a driving unit, a multi-way valve, a radiator and a cooling liquid heat exchanger, the radiator and the cooling liquid heat exchanger are arranged upstream of the driving unit, the radiator is used for heat exchange with the cooling liquid in a wind cooling mode, the cooling liquid heat exchanger is used for heat exchange between the cooling liquid and refrigerant of an air conditioning refrigerant system, and the multi-way valve is connected to the radiator, the cooling liquid heat exchanger and the driving unit; in the battery and electric drive double rapid cooling mode, the cooling liquid flows through the driving unit in sequence via the radiator, the cooling liquid heat exchanger and the multi-way valve. The application meets the rapid heat dissipation requirement of the electric drive system in a cost-effective manner and fully utilizes the existing heat management resources of the vehicle.

Description

Technical Field

[0001] This invention relates to the field of vehicle electric drive systems, and more specifically, to a control method, an electric drive thermal management system, and a vehicle. Background Technology

[0002] This section aims to provide background information relevant to understanding the various techniques described herein. As the title of this section implies, this is a discussion of related techniques that should in no way imply that they are necessarily prior art. Therefore, it should be understood that any statement in this section should be read in this context, rather than as an admission of any prior art.

[0003] With the rapid development of new energy vehicles towards high power density, long driving range, and fast charging technology, their core electric drive components (including drive motors, power inverters, DC-DC converters, etc.) are facing increasingly severe thermal management challenges. Especially under conditions of short-term high power output (such as rapid acceleration, high-speed climbing, and continuous overtaking), continuous high-load operation (such as ultra-high-speed cruising and towing), or rapid DC and boost charging, electric drive system components generate a large amount of waste heat, causing their internal temperatures to rise sharply, seriously affecting system stability and potentially impacting the vehicle's lifespan. Traditional electric drive thermal management systems mainly rely on liquid cooling circuits combined with front radiators (air cooling) for heat dissipation. This approach has the following inherent limitations: Heat dissipation capacity is limited by ambient temperature: the final heat dissipation efficiency of a radiator is highly dependent on the ambient air temperature. In high-temperature environments (such as hot summers or tropical regions) or when airflow is limited on the radiator's front side (such as during low-speed congestion or charging), the coolant's heat dissipation efficiency is low. Furthermore, in these situations, the coolant system cannot provide cooling below ambient temperature, becoming a heat dissipation bottleneck.

[0004] Traditional electric drive thermal management circuits cannot decouple their heat dissipation capacity from ambient temperature, nor can they meet the driver's need to actively reduce coolant temperature quickly through mode switching (such as switching to Sport mode) to achieve a short-term surge in vehicle performance. Radiator cooling relies on convective heat transfer between air and coolant, which has significant thermal inertia and a relatively slow response speed. When electric drive components encounter high-power loads and experience continuous short-term thermal shocks, traditional circuits struggle to dissipate heat effectively and promptly, potentially leading to short-term overheating of components, triggering power derating, impacting vehicle performance and driving experience, and even accelerating component aging.

[0005] Unable to provide “overcooling” capability to optimize efficiency and performance: Electric drive components (especially power semiconductors such as IGBT / SiC MOSFETs) have advantages in operating at room temperature: power module components can significantly reduce semiconductor on-resistance, and motor components can reduce copper winding losses, thus significantly improving system efficiency; at the same time, lower operating temperature allows the system to maintain high power output for longer periods within safe boundaries, improving the vehicle’s sustained high-speed or sustained torque performance. Summary of the Invention

[0006] The purpose of this invention is to meet the rapid heat dissipation requirements of electric drive systems in a cost-effective manner and to make full use of the vehicle's existing thermal management resources.

[0007] Furthermore, the purpose of this invention is to solve or at least alleviate one or more problems existing in the prior art.

[0008] The present invention solves the above problems by providing a control method, an electric-driven thermal management system, and a vehicle. Specifically, according to one aspect of the present invention, the following is provided: A control method for an electric drive thermal management system, wherein the control method includes the following steps: The thermal management operation mode of the electric drive thermal management system is selected based on the vehicle's operating conditions. This thermal management operation mode includes a rapid cooling mode, which further includes a dual rapid cooling mode for both the battery and electric drive. The electric thermal management system includes a drive unit, a multi-way valve, a radiator, and a coolant heat exchanger. The radiator and the coolant heat exchanger are located upstream of the drive unit. The radiator exchanges heat with the coolant via air cooling, and the coolant heat exchanger exchanges heat between the coolant and the refrigerant in the air conditioning system. The multi-way valve is connected to the radiator, the coolant heat exchanger, and the drive unit. In the battery-driven dual rapid cooling mode, the coolant flows through the drive unit sequentially via the radiator, the coolant heat exchanger, and the multi-way valve.

[0009] Optionally, according to one embodiment of the present invention, in response to one or more of the following conditions: the coolant temperature rise rate is greater than a temperature rise rate threshold, the ambient temperature is greater than a temperature threshold and the temperature difference between the output temperature of the drive unit and the ambient temperature is greater than or equal to a first temperature difference threshold, or a user command, the electric drive thermal management system is switched to the rapid cooling mode.

[0010] Optionally, according to one embodiment of the present invention, in the rapid cooling mode, one or more of the following actions are performed: Start the air conditioner compressor or adjust the speed of the air conditioner compressor; Open the electronic expansion valve of the circuit containing the coolant heat exchanger; Maintain or increase the flow rate of coolant; Turn on the heat sink.

[0011] Optionally, according to one embodiment of the present invention, the control method includes the following steps: In the rapid cooling mode, in response to the temperature difference between the output temperature of the coolant heat exchanger and the target temperature exceeding a second temperature difference threshold, the opening of the electronic expansion valve in the circuit containing the coolant heat exchanger is adjusted, wherein the target temperature is determined based on the ambient temperature.

[0012] Optionally, according to one embodiment of the present invention, the control method further includes the following steps: In response to one or more of the following conditions: the coolant temperature rise rate is less than or equal to the temperature rise rate threshold and the temperature difference between the output temperature of the drive unit and the target temperature is less than a third temperature difference threshold or the temperature difference between the output temperature and the ambient temperature is less than a fourth temperature difference threshold, a system fault, or a user command, the rapid cooling mode is exited.

[0013] Optionally, according to one embodiment of the present invention, the multi-port valve includes a first valve port, a second valve port, a third valve port, a fourth valve port, and a fifth valve port. The first valve port is connected to the coolant heat exchanger, the third valve port is connected to the radiator, the second valve port and the fifth valve port are connected to the output end of the drive unit, and the fourth valve port is connected to the input end of the drive unit.

[0014] Optionally, according to one embodiment of the present invention, the drive unit includes one or more of a power battery, a power distribution controller, and an electric drive component.

[0015] Optionally, according to one embodiment of the present invention, the power distribution controller and electric drive components for the front wheels are connected in series to form a front wheel electric drive group, and the power distribution controller and electric drive components for the rear wheels are connected in series to form a rear wheel electric drive group, wherein the front wheel electric drive group and the rear wheel electric drive group are connected in parallel, or... The power battery is connected in series with the power distribution controller for the rear wheels, and the electric drive components for the front wheels and the electric drive components for the rear wheels are connected in parallel, or... The power distribution controller for the rear wheels, the electric drive unit for the front wheels, and the electric drive unit for the rear wheels are connected in parallel.

[0016] Optionally, according to one embodiment of the present invention, in the battery-driven dual rapid cooling mode, the second valve port is connected to the third valve port, the fifth valve port is connected to the third valve port, the first valve port is connected to the output end of the coolant heat exchanger, and the fourth valve port is connected to the input end of the drive unit.

[0017] Optionally, according to one embodiment of the present invention, the electric drive thermal management system includes one or more of the following: a conventional cooling mode for the power battery, a self-circulation mode for the power battery, a rapid cooling mode for the power battery, a conventional cooling mode for the electric drive components, and a rapid cooling mode for the electric drive components, wherein the rapid cooling mode for the power battery and the rapid cooling mode for the electric drive components belong to the rapid cooling mode. In the normal cooling mode of the power battery, the fifth valve port is connected to the third valve port; In the power battery self-circulation mode, the fifth valve port is connected to the fourth valve port; In the rapid cooling mode of the power battery, the fifth valve port is connected to the first valve port; In the normal cooling mode of the electric drive component, the second valve port is connected to the third valve port; In the rapid cooling mode of the electric drive component, the second valve port is connected to the first valve port.

[0018] According to another aspect of the present invention, an electric thermal management system for performing any of the above-described control methods is provided.

[0019] According to another aspect of the present invention, a vehicle is provided, wherein the vehicle includes the above-described electric thermal management system. Attached Figure Description

[0020] Referring to the accompanying drawings, the above and other features of the present invention will become apparent, wherein, Figure 1 A schematic diagram of the operation of an electric thermal management system according to the present invention under parking charging slow charging conditions is shown. Figure 2 A schematic diagram of the operation of an electric thermal management system according to the present invention under parking charging slow charging conditions is shown. Figure 3 This diagram illustrates the operation of an electric thermal management system according to the present invention under common parking and fast charging conditions. Figure 4 This diagram illustrates the operation of an electric thermal management system according to the present invention under common parking and fast charging conditions. Figure 5 A schematic diagram of the operation of an electric thermal management system according to the present invention under DC fast charging conditions during parking is shown. Figure 6 A schematic diagram of the operation of an electric thermal management system according to the present invention under normal driving conditions is shown. Figure 7 A schematic diagram of the operation of an electric thermal management system according to the present invention under normal driving conditions is shown. Figure 8 A schematic diagram of the operation of an electric thermal management system according to the present invention under normal driving conditions is shown. Figure 9 A schematic diagram of the operation of an electric-driven thermal management system according to the present invention under harsh driving conditions is shown. Figure 10 A schematic diagram of the operation of an electric-driven thermal management system according to the present invention under harsh driving conditions is shown. Figure 11 A schematic diagram of the operation of an electric thermal management system according to the present invention under another harsh driving condition is shown; Figure 12 This diagram illustrates the adaptation of different types of drive units in an electric thermal management system according to the present invention. Figure 13 A schematic diagram illustrating the adaptation of different forms of drive units in an electric drive thermal management system according to the present invention is shown. Detailed Implementation

[0021] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0022] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive. Furthermore, the terms "first," "second," "third," and similar expressions are used for descriptive and distinguishing purposes only and should not be construed as indicating or implying the relative importance of the corresponding components.

[0023] Figure 1 A schematic diagram of the operation of an electric thermal management system according to the present invention under parking charging slow charging conditions is shown. Figure 11 A schematic diagram of the operation of an electric thermal management system according to the present invention under another harsh driving condition is shown. Arrows indicate the direction of coolant flow, red indicates hot coolant, blue indicates cooled coolant, and gray indicates no flow.

[0024] The applicant recognizes that, in order to overcome the limitations of the prior art and meet the higher requirements of high-performance electric vehicles for the thermal management of electric drive components, the next-generation thermal management system urgently needs to achieve the following key changes: Overcoming ambient temperature limitations and providing active cooling capabilities: The system must have the ability to actively cool the coolant to below ambient temperature, completely eliminating the reliance on single air cooling and providing strong "overcooling" protection for electric drive components in high-temperature environments or extreme operating conditions.

[0025] Achieving rapid response and powerful heat dissipation: The system needs to have extremely low thermal inertia and extremely high short-term heat dissipation power, so that it can intervene in the early stage when the temperature of the electric drive components rises rapidly (it is recommended that the driver switch driving modes to trigger this), quickly transfer the heat of the electric drive system, effectively suppress temperature rise, avoid derating, ensure the continuity and stability of power output, and improve the driving experience.

[0026] Intelligent on-demand active rapid cooling: The system not only needs to provide powerful cooling, but also needs to intelligently and precisely control the cooling intensity, dynamically maintaining the coolant temperature within an optimal target range below ambient temperature, optimized for electric drive components. This requires balancing optimal energy efficiency (avoiding excessive cooling and energy waste) and component safety (preventing the risk of condensation or thermal stress caused by overcooling) while rapidly cooling down. It can also intelligently switch cooling logic under different operating conditions (driving or charging).

[0027] High-efficiency integration and dynamic collaboration: The new solution needs to achieve high-efficiency integration and resource reuse with the vehicle's existing thermal management system (especially the air conditioning system), and have the ability to quickly, seamlessly, automatically or manually switch between multiple heat dissipation modes (such as conventional heat dissipation and rapid heat dissipation) according to operating conditions, so as to optimize the overall energy efficiency and cost of the system.

[0028] Currently, the industry has made many explorations in improving the heat dissipation capabilities of all-in-one electric drive systems, but there are still significant shortcomings: Enhanced front-end radiator / fans: This involves increasing the radiator area, using high-performance fans, or optimizing airflow design to improve the cooling capacity of traditional circuits. However, this only alleviates the problem to a certain extent, cannot exceed the upper limit of ambient temperature, and presents challenges in terms of space layout and NVH (noise, vibration, and harshness), with limited improvement in instantaneous thermal shock.

[0029] Independent liquid cooling loop / increased flow rate: This involves setting up an independent liquid cooling loop for the electric drive or increasing the coolant pump flow rate / pressure. This improves heat dissipation uniformity and the ability to remove heat, but the core heat dissipation still relies on the radiator, thus failing to provide sub-ambient temperature cooling. Increasing the flow rate also increases parasitic power consumption.

[0030] Indirect coupling of air conditioning cooling capacity: Some high-end models utilize the chiller (refrigerant-coolant heat exchanger) in the battery thermal management system to cool the battery coolant and attempt to indirectly transfer some of the cooling capacity to the electric drive circuit via the heat exchanger. This method suffers from problems such as long path, high thermal resistance, slow response, significant cooling capacity loss, and complex control, making it difficult to meet the cooling requirements of the electric drive components. Furthermore, it may interfere with the battery's own thermal management needs.

[0031] Dedicated refrigerant direct cooling: Some studies have attempted to directly introduce refrigerant into the motor housing or power module for evaporative cooling (similar to direct battery cooling). While this solution can provide powerful cooling capabilities, it faces challenges such as high system complexity (requiring an independent high-pressure refrigerant circuit for electric drive), significant sealing and reliability risks, complex refrigerant charge management, high costs, and potential condensate control difficulties, making it far from large-scale engineering applications.

[0032] In summary, none of the aforementioned new energy vehicle electric drive thermal management solutions, whether traditional enhancement methods or emerging indirect coupling or direct cooling explorations, have effectively addressed the core requirement of providing powerful heat dissipation below ambient temperature on demand, rapidly, and precisely under high-temperature environments or extreme operating conditions. The market urgently needs an innovative solution for rapid heat dissipation that can fully utilize existing vehicle thermal management resources (especially the air conditioning refrigerant system) while achieving high efficiency, reliability, and intelligent controllability.

[0033] Therefore, the present invention relates to a control method for an electric thermal management system 100, wherein the control method includes the following steps: The thermal management operation mode of the electric drive thermal management system 100 is selected based on the vehicle's operating conditions. This thermal management operation mode includes a rapid cooling mode, which further includes a dual rapid cooling mode for both the battery and electric drive. The electric thermal management system 100 includes a drive unit 1, a multi-way valve 2, a radiator 3, and a coolant heat exchanger 4. The radiator 3 and the coolant heat exchanger 4 are located upstream of the drive unit 1. The radiator 3 exchanges heat with the coolant via air cooling, and the coolant heat exchanger 4 exchanges heat between the coolant and the refrigerant in the air conditioning system. The multi-way valve 2 is connected to the radiator 3, the coolant heat exchanger 4, and the drive unit 1. In the battery-driven dual rapid cooling mode, the coolant flows sequentially through the radiator 3, the coolant heat exchanger 4, and the multi-way valve 2 through the drive unit 1. For example, the downstream of the multi-way valve 2 is connected to the radiator 3 and the drive unit 1, and the upstream of the multi-way valve 2 is connected to the coolant heat exchanger 4.

[0034] It should be understood that the terms "upstream" and "downstream" in a multi-way valve are relative to the direction of coolant flow. Coolant can flow into the multi-way valve upstream and flow out of the multi-way valve downstream. Furthermore, those skilled in the art can understand the connection relationships between the technical features (e.g., the multi-way valve and surrounding components) and the direction of coolant flow in a reasonable manner after reading the various technical solutions of this invention.

[0035] It should also be understood that coolant heat exchangers are sometimes called chillers, and depending on their function, they can also be called refrigerant-coolant heat exchangers. In this technical solution, the heat exchanger of the vehicle's air conditioning refrigerant system is used to exchange heat with the coolant, making full use of existing resources, offering strong compatibility and cost savings. Simultaneously, the use of a multi-way valve allows the thermal management system to achieve rapid switching of cooling modes in a cost-effective manner, providing flexible cooling for the electric drive system. It should also be understood that "connected" does not mean always "connected," but rather that the opening and closing of the multi-way valve's ports can be switched according to actual needs.

[0036] In this solution, the quench circuit incorporates compressor capability, decoupling the coolant temperature from the ambient temperature and making it suitable for a wide temperature range. In other words, through the compressor-cooled circuit, the chiller can supply coolant to the electric drive system at a temperature significantly lower than the ambient temperature (e.g., at an ambient temperature of 35°C, the inlet coolant temperature can be reduced to 5-10°C via the compressor), providing a better heat dissipation boundary. If a conventional circuit is used, the minimum inlet coolant temperature of the electric drive system is strongly correlated with the ambient temperature (e.g., at an ambient temperature of 35°C, the coolant temperature in a conventional circuit during a cold start is 30°C, and as the vehicle is driven, the final inlet coolant temperature will not fall below the ambient temperature of 35°C).

[0037] For example, in conventional mode, the coolant is cooled by a radiator of air cooling type, while in rapid cooling mode, the coolant is cooled quickly and efficiently by a heat exchanger. If necessary, both the radiator and the heat exchanger can be used for cooling simultaneously. Therefore, the thermal management system of the present invention enables the cooling capacity of the heat exchanger to be introduced to the components requiring cooling as needed.

[0038] Depending on the circuit design requirements, the electric thermal management system may also include a circulating pump 5 (e.g., configured as an electric water pump) and a multi-way valve 6, which can be an electric valve or a non-electric valve. In the latter case, those skilled in the art will understand that, for example, through an overall flow resistance design, the flow distribution can be automatically achieved by controlling only the multi-way valve and the water pump. The circulating pump can then be used to regulate the flow rate of the coolant.

[0039] In some embodiments of this disclosure, the control method includes the following steps: In response to one or more of the following conditions: the coolant temperature rise rate is greater than the temperature rise rate threshold, the ambient temperature is greater than the temperature threshold and the temperature difference between the output temperature of the drive unit 1 and the ambient temperature is greater than or equal to the first temperature difference threshold, or a user command, the electric drive thermal management system 100 is switched to the rapid cooling mode, such as the power battery rapid cooling mode, the electric drive component rapid cooling mode, or the battery and electric drive dual rapid cooling mode, which will be explained in detail below.

[0040] The temperature rise rate threshold varies depending on the specific vehicle model. For example, for a small sports car, the value can be set at 2-5℃ / min. Furthermore, if the vehicle has corresponding driving modes, the thermal management system can switch to rapid cooling mode when the appropriate mode is selected. Specifically, vehicles typically have multiple driving modes, such as Eco, Comfort, Sport, and Track. Therefore, the rapid cooling mode of the thermal management system can be linked to modes related to aggressive driving (such as Track and Sport modes) to improve the vehicle's driving performance under intense conditions.

[0041] It's important to note that the coolant temperature rise rate can be expressed as dT / dt. Specifically, it can depend on factors such as the instantaneous power of the motor / inverter, the motor torque demand, or the estimated IGBT junction temperature exceeding a corresponding threshold, or the vehicle being in DC fast charging mode (where high current causes severe heating of the power distribution unit, PDU). All of these factors can influence the coolant temperature rise rate. Specifically, the instantaneous power of the motor / inverter, the motor torque demand, or the estimated IGBT junction temperature exceeding the corresponding threshold can be understood as the vehicle being under harsh driving conditions, such as hill climbing. Furthermore, the coolant temperature rise rate can be understood as the coolant temperature rise rate at the maximum flow rate boundary. Different vehicle models have different flow rate capabilities, but the typical maximum flow rate boundary is 12 liters per minute.

[0042] The temperature threshold is 55 degrees Celsius for example, and the first temperature difference threshold is 5 degrees Celsius for example. That is, when the ambient temperature is greater than the temperature threshold and the temperature difference between the output temperature of the drive unit (i.e., the temperature of the coolant at the output end) and the ambient temperature is greater than or equal to the first temperature difference threshold, the vehicle can be considered to be in a high temperature condition, and various rapid cooling modes can be triggered to rapidly cool down the vehicle.

[0043] For high-temperature conditions, it is also feasible to predict that the output temperature of the drive unit will exceed the safety threshold or cause derating within X seconds in the future. This can trigger the rapid cooling mode in advance to pre-cool the vehicle, so that the vehicle can better cope with the high temperature conditions that are about to arrive.

[0044] It is feasible to perform one or more of the following actions in the rapid cooling mode, such as the power battery rapid cooling mode, the electric drive component rapid cooling mode, or the battery and electric drive dual rapid cooling mode: Start the air conditioner compressor or adjust the speed of the air conditioner compressor; Open the electronic expansion valve (expansion valve of the air conditioning circuit) of the circuit where the coolant heat exchanger 4 is located. Maintain or increase the flow rate of coolant; Start the heat sink 3.

[0045] Starting or adjusting the air conditioning compressor activates the heat exchanger or enhances its heat exchange capacity. Opening the expansion valve in the air conditioning circuit allows the coolant temperature at the input of the electric drive system to drop rapidly for a quenching effect; the opening degree of the expansion valve can be estimated based on the ambient temperature and heat load. Maintaining or increasing the coolant flow rate can be achieved by adjusting the speed of the coolant pump, which can be optimized based on flow requirements (heat load) and system pressure drop to ensure heat exchange efficiency. Starting the radiator can be considered an auxiliary cooling method. Although the radiator circuit is usually closed at this time (the circuit has switched to the heat exchanger circuit), auxiliary cooling can be activated, for example, through component expansion, in cases of extreme high temperatures or excessively high refrigerant system pressure (e.g., ...). Figure 9 Among these, component expansion can include, for example, adding multi-way valves, water pumps, or adjusting the overall piping layout.

[0046] The control method may also include the following steps: In the rapid cooling mode of the power battery, the rapid cooling mode of the electric drive component, or the dual rapid cooling mode of the battery and electric drive, in response to the temperature difference between the output temperature of the coolant heat exchanger 4 and the target temperature exceeding the second temperature difference threshold, the opening of the electronic expansion valve in the circuit where the coolant heat exchanger 4 is located is adjusted, wherein the target temperature is determined based on the ambient temperature.

[0047] This technical solution provides an example of controlling the coolant temperature at the heat exchanger output in a rapid cooling mode. Here, the second temperature difference threshold is, for example, 5°C; the target temperature can be determined based on the ambient temperature and the current heat load of the component, for example, the relationship between the target temperature and the ambient temperature is, for example, target temperature = ambient temperature - (5 to 15 degrees), so that the target temperature is lower than the ambient temperature.

[0048] The specific offset (i.e., 5 to 15 degrees in this example) is determined using a pre-defined optimized MAP. This MAP is based on: Optimal efficiency: the efficiency-temperature characteristics of the motor and inverter at different power / speeds. Performance limits: set to allow components to withstand higher / longer loads at safe temperatures. Furthermore, model predictive control can be used to optimize the target temperature in real time. Inputs: Measured value of T_chiller_out, T_target, T_in_drive (optional), P_high, P_low (calculate the refrigerant's superheat / subcooling).

[0049] The control method may also include the following steps: In response to one or more of the following conditions: the coolant temperature rise rate is less than or equal to the temperature rise rate threshold and the temperature difference between the output temperature of the drive unit 1 and the target temperature is less than the third temperature difference threshold or the temperature difference between the output temperature and the ambient temperature is less than the fourth temperature difference threshold, system failure, or user instruction, the drive unit exits the rapid cooling mode of the power battery, the rapid cooling mode of the electric drive component, or the dual rapid cooling mode of the battery and electric drive.

[0050] This technical solution provides an example of exiting the rapid cooling mode. System faults include abnormal refrigerant pressure and sensor failure; overheating is triggered by the electrically driven system itself, leading to derating. A third temperature difference threshold is, for example, 5 degrees Celsius, and a fourth temperature difference threshold is, for example, -10 degrees Celsius, to ensure the temperature has safely dropped before exiting the rapid cooling mode. A coolant temperature rise rate less than or equal to the temperature rise rate threshold indicates that the high load conditions have disappeared, such as when motor power or torque drops below the threshold or DC fast charging has ended. After exiting the rapid cooling mode, the system can switch to normal cooling mode or self-circulation mode depending on the actual situation.

[0051] The drive unit 1 includes one or more of the following: a power battery 11, an intelligence power unit (IPU, central intelligent power distribution controller), and an electric drive system (EDS). Figure 1For example, circulation pumps are installed upstream of the power battery branch and upstream of the common EDS and IPU, respectively, which can be regarded as the first circulation pump 51 and the second circulation pump 52. Five multi-way valves are also provided: the first multi-way valve 61 is located between the radiator and the second circulation pump; the second multi-way valve 62 is located between the first multi-way valve and the heat exchanger; the third multi-way valve 63 is located between the second multi-way valve and the first circulation pump; the fourth multi-way valve 64 is located between the second circulation pump and the power distribution controller; and the fifth multi-way valve 65 is located between the multi-port valve (second valve port) and the electric drive components. Thus, various cooling modes are switched by coordinating the opening and closing of each multi-way valve. Furthermore, the electric drive components include, for example, the motor (EM), differential (GB), and controller (PEU), and sometimes the power distribution controller can be integrated. Depending on actual needs (e.g., different operating modes or different thermal management system structures), the number, arrangement, and specifications of each circulation pump or multi-way valve can be flexibly adjusted.

[0052] In some embodiments of the present invention, the multi-port valve 2 includes a first valve port 21, a second valve port 22, a third valve port 23, a fourth valve port 24, and a fifth valve port 25. The first valve port 21 is connected to the coolant heat exchanger 4, the third valve port 23 is connected to the radiator 3, the second valve port 22 and the fifth valve port 25 are connected to the output end of the drive unit 1, and the fourth valve port 24 is connected to the input end of the drive unit 1.

[0053] Therefore, a multi-way valve is exemplarily constructed as a five-way valve. Through the connection design of each valve port, the flow direction of the coolant can be distributed as needed, thus enabling switching between normal and rapid cooling modes. Furthermore, it does not significantly alter the overall thermal management system loop, thus exhibiting good compatibility. Specifically, an electrically controlled five-way ball valve or an electrically controlled five-way slide valve can be selected, and more channels can be provided to match more complex systems. Regarding control accuracy, a multi-way valve with fast response speed (<500ms), low leakage, support for rapid switching of the thermal management loop, and low failure rate can be considered.

[0054] Regarding heat exchangers, it is feasible to construct them as plate heat exchangers or shell-and-tube heat exchangers, which can be optimized for high heat exchange efficiency and low pressure drop. On the refrigerant side, it can be connected to a dedicated electronic expansion valve and independent refrigerant piping, forming a branch in parallel with the crew compartment evaporator, ensuring that the refrigerant flow can be independently and precisely controlled. On the coolant side, the heat exchanger is connected in series in the quench circuit, with interface dimensions matching the main circuit, thereby enabling heat exchange between the coolant and refrigerant when rapid cooling is required.

[0055] Figure 2 A schematic diagram of the operation of an electric thermal management system according to the present invention under parking charging slow charging conditions is shown. Figure 3 and Figure 4 This diagram illustrates the operation of an electric thermal management system according to the present invention under common parking and fast charging conditions. Figure 5 A schematic diagram of the operation of an electric thermal management system according to the present invention under DC fast charging conditions during parking is shown. Figures 6 to 8 A schematic diagram of the operation of an electric thermal management system according to the present invention under normal driving conditions is shown. Figure 9 and Figure 10 A schematic diagram of the operation of an electric-driven thermal management system according to the present invention under harsh driving conditions is shown. Figure 11 A schematic diagram of the operation of an electric thermal management system according to the present invention under another harsh driving condition is shown.

[0056] The electric drive thermal management system 100 provides one or more of the following operating modes for each cooling component: conventional cooling mode for the power battery, self-circulation mode for the power battery, rapid cooling mode for the power battery, conventional cooling mode for the electric drive components, rapid cooling mode for the electric drive components, and dual rapid cooling mode for both the battery and the electric drive components. The rapid cooling mode for the power battery and the rapid cooling mode for the electric drive components are both considered rapid cooling modes. In the normal cooling mode of the power battery, the fifth valve port 25 is connected to the third valve port 23; In the power battery self-circulation mode, the fifth valve port 25 is connected to the fourth valve port 24; In the rapid cooling mode of the power battery, the fifth valve port 25 is connected to the first valve port 21; In the normal cooling mode of the electric drive component, the second valve port 22 is connected to the third valve port 23; In the rapid cooling mode of the electric drive component, the second valve port 22 is connected to the first valve port 21.

[0057] Alternatively, in the battery-driven dual rapid cooling mode, the second valve port 22 is connected to the third valve port 23, the fifth valve port 25 is connected to the third valve port 23, the first valve port 21 is connected to the output end of the coolant heat exchanger 4, and the fourth valve port 24 is connected to the input end of the drive unit 1.

[0058] These modes of the thermal management system can be matched with vehicle operating conditions. For example, the (AC) slow charging condition during parking is associated with a normal cooling mode and a battery self-circulation mode; the (AC, DC) fast charging condition during parking is associated with a normal cooling mode for the electric drive components and a normal or rapid cooling mode for the power battery; the DC fast charging condition during parking is associated with a rapid cooling mode for both the power battery and the electric drive components; the normal driving condition is associated with a normal cooling mode for both the power battery and the electric drive components, a normal cooling mode for both the electric drive components and the rapid cooling mode for the power battery, or a normal cooling mode for both the electric drive components and the battery self-circulation mode; the harsh driving condition is associated with a rapid cooling mode for both the power battery and the electric drive components, or a rapid cooling mode for both the electric drive components and the battery self-circulation mode; another harsh driving condition can also be associated with a dual rapid cooling mode for both the battery and the electric drive. Thus, different operating modes can be executed according to different vehicle operating conditions; in other words, the thermal management system of the present invention can support many vehicle operating conditions. For example, driving under harsh conditions for 30 minutes at 200 kph.

[0059] Specifically, in the conventional cooling mode of the power battery, the coolant exchanges heat through the radiator and is used to cool the power battery. At the same time, if the electric drive components and the power distribution controller do not require heat dissipation, the corresponding multi-way valves can be set to the open state.

[0060] In the battery self-circulation mode, the coolant does not exchange heat with the radiator or heat exchanger, but only flows through the battery (as well as the multi-way valve and water pump). This means the coolant utilizes the battery's own heat for heat exchange, which is useful, for example, in situations where battery insulation is required in winter. Meanwhile, if the electric drive components and power distribution controller do not require cooling, the corresponding multi-way valve can be set to the off state.

[0061] In the conventional cooling mode for the electric drive components, the coolant exchanges heat via the radiator and is used to cool the electric drive components and the power distribution controller (depending on their position). Simultaneously, if the power battery also requires conventional cooling, the coolant exchanges heat via the radiator and is used to cool the power battery. Therefore, the coolant provides conventional cooling for all three components simultaneously, and the confluence of coolant flows is achieved through the opening of the second, third, and fifth valve ports.

[0062] In the rapid cooling mode of the power battery, the coolant undergoes rapid heat exchange via a heat exchanger before flowing through the power battery to complete cooling. Simultaneously, the coolant also exchanges heat via a radiator and is used to cool the electric drive components and the power distribution controller (depending on their location). However, if the electric drive components also require rapid cooling (e.g., in the case of DC fast charging), the coolant is diverted to the heat exchanger for rapid heat exchange by opening the second, first, and fifth ports of a multi-way valve.

[0063] In the dual rapid cooling mode of battery-electric drive, the coolant first undergoes heat exchange through the radiator, then rapid heat exchange through the heat exchanger, and finally is distributed to the drive unit, such as the power battery, power distribution controller, and electric drive components. The coolant flow is achieved by opening the second, third, and fifth ports of a multi-way valve, and the cooled coolant is input through the heat exchanger to the first port, and output through the fourth port.

[0064] Figure 12 This diagram illustrates the adaptation of different types of drive units in an electric thermal management system according to the present invention. Figure 13 A schematic diagram illustrating the adaptation of different forms of drive units in an electric drive thermal management system according to the present invention is shown.

[0065] A power distribution controller 13 for the front wheels and an electric drive unit 12 for the front wheels are connected in series to form a front wheel electric drive group. A power distribution controller 15 for the rear wheels and an electric drive unit 14 for the rear wheels are connected in series to form a rear wheel electric drive group. The front wheel electric drive group and the rear wheel electric drive group are connected in parallel, or... The power battery is connected in series with the power distribution controller for the rear wheels, and the electric drive components for the front wheels and the electric drive components for the rear wheels are connected in parallel, or... The power distribution controller for the rear wheels, the electric drive unit for the front wheels, and the electric drive unit for the rear wheels are connected in parallel.

[0066] This technical solution demonstrates that the drive unit is modular, and the connection relationships between its power battery, power distribution controller, and electric drive components can be adjusted as needed. The circuit design can also be adaptively adjusted, resulting in strong scalability for the entire system. For example, Figure 12 The integration scheme of the power distribution controller and the power battery was demonstrated, and both were in rapid cooling mode, while the electric drive components did not require heat dissipation. Figure 13 This demonstrates a scheme where the power distribution controller operates as an independent circuit. A second multi-way valve 7 can be added to configure the coolant flow path for this independent circuit. In this configuration, both the power battery and the power distribution controller are in rapid cooling mode, while the electric drive components do not require heat dissipation.

[0067] The present invention also relates to an electric thermal management system 100 for performing any of the above control methods; and to a vehicle, wherein the vehicle includes the electric thermal management system 100.

[0068] Therefore, the specific implementation methods and corresponding technical effects of the electric thermal management system and vehicle of the present invention can be understood by referring to the various control methods of the present invention, and will not be repeated here.

[0069] In summary, this invention, through a multi-way valve and full utilization of the air conditioning refrigerant system, enables on-demand switching between conventional cooling circuits and rapid cooling circuits, ultimately achieving the following effects: 1. Improve the maximum vehicle speed / maximum speed duration under normal operating conditions, such as the ability to operate under continuous load; 2. Improve the vehicle's power performance under high-temperature conditions, such as short-term high-power output capability; 3. Enhance IPU capabilities to protect PDU / DC-DC components under high-current DC / AC charging conditions. For example, improve the charging stability of IPU components during DC supercharging (5C or higher current). 4. Improve the output torque capacity of PEU to support low-speed, high-torque conditions and enhance the vehicle's ability to get out of trouble; 5. Minimize water temperature rise to 55+ degrees Celsius, optimize water temperature distribution throughout the electric drive system's lifecycle, and improve system durability; 6. High versatility: one mode can be used for multiple working conditions, balancing system cost and scalability.

[0070] It should be understood that all the above preferred embodiments are exemplary and not restrictive, and various modifications or variations made by those skilled in the art to the specific embodiments described above under the concept of the present invention should be within the legal protection scope of the present invention.

Claims

1. A control method for an electric thermal management system (100), characterized in that, The control method includes the following steps: The thermal management operation mode of the electric drive thermal management system (100) is selected based on the vehicle's operating conditions. The thermal management operation mode includes a rapid cooling mode, which includes a dual rapid cooling mode for both battery and electric drive. The electric thermal management system (100) includes a drive unit (1), a multi-way valve (2), a radiator (3), and a coolant heat exchanger (4). The radiator (3) and the coolant heat exchanger (4) are arranged upstream of the drive unit (1). The radiator (3) is used to exchange heat with the coolant in an air-cooled manner, and the coolant heat exchanger (4) is used to exchange heat between the coolant and the refrigerant of the air conditioning refrigerant system. The multi-way valve (2) is connected to the radiator (3), the coolant heat exchanger (4), and the drive unit (1). In the battery-driven dual rapid cooling mode, the coolant flows through the radiator (3), the coolant heat exchanger (4), and the multi-way valve (2) sequentially through the drive unit (1). The multi-port valve (2) includes a first valve port (21), a second valve port (22), a third valve port (23), a fourth valve port (24), and a fifth valve port (25). The first valve port (21) is connected to the coolant heat exchanger (4), the third valve port (23) is connected to the radiator (3), the second valve port (22) and the fifth valve port (25) are connected to the output end of the drive unit (1), and the fourth valve port (24) is connected to the input end of the drive unit (1). The drive unit (1) includes one or more of a power battery (11), a power distribution controller, and an electric drive component. The electric drive thermal management system (100) includes one or more of the following: a power battery conventional cooling mode, a power battery self-circulation mode, a power battery rapid cooling mode, an electric drive component conventional cooling mode, and an electric drive component rapid cooling mode. The power battery rapid cooling mode and the electric drive component rapid cooling mode belong to the rapid cooling mode. In the normal cooling mode of the power battery, the fifth valve port (25) is connected to the third valve port (23); In the self-circulation mode of the power battery, the fifth valve port (25) is connected to the fourth valve port (24); In the rapid cooling mode of the power battery, the fifth valve port (25) is connected to the first valve port (21); In the normal cooling mode of the electric drive component, the second valve port (22) is connected to the third valve port (23); In the rapid cooling mode of the electric drive component, the second valve port (22) is connected to the first valve port (21).

2. The control method according to claim 1, characterized in that, In response to one or more of the following conditions: the coolant temperature rise rate is greater than the temperature rise rate threshold, the ambient temperature is greater than the temperature threshold and the temperature difference between the output temperature of the drive unit (1) and the ambient temperature is greater than or equal to the first temperature difference threshold, or a user instruction, the electric drive thermal management system (100) is switched to the rapid cooling mode.

3. The control method according to claim 1, characterized in that, In the rapid cooling mode, one or more of the following actions are performed: Start the air conditioner compressor or adjust the speed of the air conditioner compressor; Open the electronic expansion valve of the circuit containing the coolant heat exchanger (4); Maintain or increase the flow rate of coolant; Start the heat sink (3).

4. The control method according to claim 2, characterized in that, The control method further includes the following steps: In the rapid cooling mode, in response to the temperature difference between the output temperature of the coolant heat exchanger (4) and the target temperature exceeding the second temperature difference threshold, the opening of the electronic expansion valve of the circuit containing the coolant heat exchanger (4) is adjusted, wherein the target temperature is determined based on the ambient temperature.

5. The control method according to claim 4, characterized in that, The control method further includes the following steps: In response to one or more of the following conditions: the coolant temperature rise rate is less than or equal to the temperature rise rate threshold and the temperature difference between the output temperature of the drive unit (1) and the target temperature is less than the third temperature difference threshold or the temperature difference between the output temperature and the ambient temperature is less than the fourth temperature difference threshold, system failure, or user instruction, the rapid cooling mode is exited.

6. The control method according to claim 1, characterized in that, The power distribution controller and electric drive components for the front wheels are connected in series to form a front-wheel electric drive assembly, and the power distribution controller and electric drive components for the rear wheels are connected in series to form a rear-wheel electric drive assembly. The front-wheel electric drive assembly and the rear-wheel electric drive assembly are connected in parallel, or... The power battery is connected in series with the power distribution controller for the rear wheels, and the electric drive components for the front wheels and the electric drive components for the rear wheels are connected in parallel, or... The power distribution controller for the rear wheels, the electric drive unit for the front wheels, and the electric drive unit for the rear wheels are connected in parallel.

7. The control method according to claim 1, characterized in that, In the battery-driven dual rapid cooling mode, the second valve port (22) is connected to the third valve port (23), the fifth valve port (25) is connected to the third valve port (23), the first valve port (21) is connected to the output end of the coolant heat exchanger (4), and the fourth valve port (24) is connected to the input end of the drive unit (1).

8. An electric thermal management system (100) for performing the control method according to any one of claims 1 to 7.

9. A vehicle, characterized in that, The vehicle includes the electric thermal management system (100) according to claim 8.

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