A whole vehicle thermal management mode control method for an electric vehicle

Abstract

The application discloses a kind of whole vehicle thermal management mode control methods of electric vehicle, comprising: obtaining the device state and environmental parameters of electric vehicle;According to device state, determine TMS state, TMS state includes: TMS is not ready state, TMS preparation state;When the TMS state is TMS is not ready, the controller specified execution control scheme is original state control scheme;According to TMS state and device state, determine driving state, the driving state includes standby state, charging state and driving state;According to driving state, judge whether the controller enters thermal management mode, if enter thermal management mode, according to environmental parameters, execute thermal management mode switching, send control scheme corresponding control instruction to electric vehicle device.According to the above technical solution, it can solve the problem of cockpit and battery pack refrigeration coupling influence, single refrigeration control working condition, mutual interference of internal condenser and evaporator, realize the refrigeration optimization control of battery and cab under various working conditions.

Description

Technical Field

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

[0002] In the comprehensive management of electric vehicle control, the vehicle thermal management system is a complex, multi-coupled, nonlinear system. Only through mutual coordination among the various subsystems can the system's cooling efficiency and performance be guaranteed. The electric vehicle thermal management system needs to obtain the subsystem status to determine the next thermal management mode, maximizing the charging and discharging characteristics of the battery pack, improving driver comfort, extending the lifespan of components, and minimizing energy loss while ensuring cooling effectiveness during vehicle charging, discharging, and driving.

[0003] In practical applications, the following problems may still be encountered due to differences in driving conditions and cooling requirements:

[0004] (1) The instantaneous switching of cooling demand will affect the cooling effect of other subsystems that retain cooling: for example, when the battery pack is in cooling mode, if the power is suddenly increased to turn on the cooling mode of the cockpit, the cooling effect of the battery pack will be greatly reduced; when both the battery pack and the cockpit are in cooling mode, if the cooling mode of the battery pack is suddenly turned off, the temperature of the cockpit will drop rapidly, affecting the comfort of the cockpit.

[0005] (2) Single cooling control mode: Traditional battery thermal management does not fully consider the different cooling needs under different operating conditions, resulting in unreasonable energy distribution and waste;

[0006] (3) The refrigerant circuit is a closed loop formed by the compressor, internal condenser and evaporator. There is a heat exchange coupling phenomenon between the internal condenser and evaporator, which means that the air temperature output to the cockpit cannot meet the temperature requirements.

[0007] To address the issues of cooling coupling between the cockpit and battery pack, the single operating mode of cooling control, and mutual interference between the internal condenser and evaporator, a technical solution for the overall thermal management of electric vehicles is needed. This solution should enable efficient switching and control of thermal management modes, provide optimized cooling control for the battery and cockpit under various operating conditions, and avoid mutual interference between modes and unreasonable energy distribution. Summary of the Invention

[0008] To achieve the above objectives, this application provides a method for controlling the thermal management mode of an electric vehicle, comprising the following steps:

[0009] Acquire the device status and environmental parameters of the electric vehicle; device status includes: auxiliary drive relay status, PT pressure sensor status, three-state pressure switch, and compressor status; environmental parameters include: PTC switch position, key position, AC switch, cabin temperature, chiller outlet temperature, and peak power of the maximum available discharge of the BMS.

[0010] The TMS status is determined based on the device status. The TMS status includes: TMS not ready and TMS ready. When the TMS status is TMS not ready, the controller is assigned the original state control scheme.

[0011] The vehicle status is determined based on the TMS status and device status. The vehicle status includes standby status, charging status and driving status.

[0012] The controller determines whether to enter thermal management mode based on the vehicle's driving status. If it does, it switches to thermal management mode based on environmental parameters and sends control commands corresponding to the control scheme to the electric vehicle components. The control scheme refers to the controller's control output commands, which include: control timing, solenoid valve operation, water pump speed, electronic expansion valve operation, compressor speed, and air conditioning fan speed and duty cycle adjustment.

[0013] Furthermore, before switching the thermal management mode based on environmental parameters, standard values ​​for environmental parameters are defined, including: standard value for cockpit temperature, standard value for chiller outlet temperature, and standard value for peak power of maximum available discharge of BMS; among which, the standard value for cockpit temperature also includes a second standard value for cockpit temperature, and the standard value for chiller outlet temperature also includes a second standard value for chiller outlet temperature, a third standard value for chiller outlet temperature, and a fourth standard value for chiller outlet temperature.

[0014] Determining whether the controller enters thermal management mode based on the driving status means that when the driving status is driving or charging, the controller enters thermal management mode based on the environmental parameters.

[0015] Furthermore, the second standard value of the cockpit temperature is defined as being less than the standard value of the cockpit temperature; the second standard value of the chiiller outlet temperature is defined as being greater than the standard value of the chiiller outlet temperature, the fourth standard value of the chiiller outlet temperature is defined as being less than the standard value of the chiiller outlet temperature, and the third standard value of the chiiller outlet temperature is defined as being less than the fourth standard value of the chiiller outlet temperature.

[0016] The thermal management modes include cab-related thermal management modes and battery pack-only thermal management modes:

[0017] The cab-related thermal management modes include: cab cooling and battery pack initial shutdown, cab cooling and battery pack cooling, cab cooling and battery pack temporary shutdown, and cab cooling and battery pack self-circulation.

[0018] The battery pack's thermal management modes include: initial shutdown, cooling, temporary shutdown, and self-circulation.

[0019] When environmental parameters meet the following conditions: the PTC switch is not pressed, the key is on, and the AC switch is active, the controller can switch to the cab-related thermal management mode and assign one or more control schemes to the controller, including:

[0020] The cab cooling and battery pack initial shutdown control scheme corresponds to the cab cooling and battery pack initial shutdown control scheme.

[0021] The cab cooling and battery pack cooling systems include a first control scheme, a second control scheme, a third control scheme, and a fourth control scheme.

[0022] The cab cooling and battery pack temporary shutdown includes a first control scheme for cab cooling and battery pack temporary shutdown and a second control scheme for cab cooling and battery pack temporary shutdown;

[0023] The cab cooling and battery pack self-circulation system includes a first control scheme for cab cooling and battery pack self-circulation and a second control scheme for cab cooling and battery pack self-circulation.

[0024] When environmental parameters meet the following conditions: PTC switch is pressed, key is not engaged, and AC switch is inactive, the controller can switch to battery pack-only thermal management mode and specify one or more control schemes to be executed for the controller, including:

[0025] The battery pack initial state shutdown includes a first control scheme for battery pack initial state shutdown and a second control scheme for battery pack initial state shutdown;

[0026] The battery pack cooling system includes a first control scheme, a second control scheme, and a third control scheme.

[0027] The battery pack temporary shutdown includes a first control scheme for battery pack temporary shutdown and a second control scheme for battery pack temporary shutdown;

[0028] The battery pack self-circulation includes a first control scheme for battery pack self-circulation and a second control scheme for temporary shutdown of the battery pack.

[0029] Furthermore, the switching of thermal management modes includes:

[0030] When the thermal management mode is the initial shutdown of the battery pack, it can be switched to cab cooling and battery pack initial shutdown. The output control scheme is the cab cooling and battery pack initial shutdown control scheme.

[0031] When the thermal management mode is battery pack self-circulation, it can be switched to cab cooling and battery pack cooling. The output control scheme is the first control scheme for cab cooling and battery pack cooling.

[0032] When the battery pack is initially shut down, the thermal management mode can be switched to cab cooling and battery pack cooling. The output control scheme is a second control scheme for cab cooling and battery pack cooling.

[0033] When the thermal management mode is battery pack cooling, it can be switched to cab cooling and battery pack cooling. The output control scheme is a third control scheme for cab cooling and battery pack cooling.

[0034] When the thermal management mode is cab cooling and battery pack initial shutdown or cab cooling and battery pack self-circulation, it can be switched to cab cooling and battery pack cooling. The output control scheme is the fourth control scheme for cab cooling and battery pack cooling.

[0035] When the thermal management mode is cab cooling and battery pack cooling or battery pack cooling, it can be switched to cab cooling and battery pack temporary shutdown. The output control scheme is the first control scheme for cab cooling and battery pack temporary shutdown.

[0036] When the thermal management mode is temporarily shut down, it can be switched to cab cooling and battery pack temporary shutdown. The output control scheme is the second control scheme for cab cooling and battery pack temporary shutdown.

[0037] When the thermal management mode is temporary shutdown of the battery pack or battery pack self-circulation, it can be switched to cab cooling and battery pack self-circulation. The output control scheme is the first control scheme of cab cooling and battery pack self-circulation.

[0038] When the thermal management mode is cab cooling and the battery pack is temporarily shut down, it can be switched to cab cooling and battery pack self-circulation mode. The output control scheme is the second control scheme for cab cooling and battery pack self-circulation.

[0039] When the thermal management mode is cab cooling and the battery pack is in initial shutdown mode, it can be switched to battery pack initial shutdown mode, and the output control scheme is the second control scheme for battery pack initial shutdown mode.

[0040] When the thermal management mode is cab cooling and battery pack cooling, it can be switched to battery pack cooling, and the output control scheme is the first control scheme for battery pack cooling;

[0041] When the thermal management mode is the initial shutdown of the battery pack or the battery pack self-circulation mode, it can be switched to battery pack cooling, and the output control scheme is the second control scheme for battery pack cooling.

[0042] When the thermal management mode is cab cooling and battery pack initial shutdown or cab cooling and battery pack self-circulation, it can be switched to battery pack cooling, and the output control scheme is the third control scheme for battery pack cooling.

[0043] When the thermal management mode is cab cooling and battery pack cooling or when the battery pack is cooling, it can be switched to battery pack temporary shutdown. The output control scheme is the first control scheme for battery pack temporary shutdown.

[0044] When the thermal management mode is cab cooling and battery pack is temporarily shut down, it can be switched to battery pack temporary shutdown, and the output control scheme is the second control scheme for battery pack temporary shutdown;

[0045] When the battery pack is temporarily shut down, the thermal management mode can be switched to battery pack self-circulation mode, and the output control scheme is the first control scheme for battery pack self-circulation.

[0046] When the thermal management mode is cab cooling and battery pack temporary shutdown or cab cooling and battery pack self-circulation, it can be switched to battery pack self-circulation, and the output control scheme is the second control scheme for battery pack self-circulation.

[0047] According to the present invention, the characteristics of each component of an electric vehicle can be fully utilized to achieve efficient switching and control of thermal management modes, solve the problems of cooling coupling between the cab and the battery pack, single cooling control conditions, and mutual interference between the internal condenser and evaporator, and realize optimized cooling control of the battery and the cab under various operating conditions. Attached Figure Description

[0048] Figure 1 This is a flowchart illustrating the steps of a thermal management mode control method according to an embodiment of the present invention;

[0049] Figure 2 This is a layout diagram of a thermal management system controlled by the thermal management mode control method provided in an embodiment of the present invention;

[0050] Figure 3 This is a network topology diagram of a thermal management system controlled by the thermal management mode control method provided in an embodiment of the present invention;

[0051] Figure 4 This is a control principle diagram of the thermal management system provided by the thermal management mode control method according to an embodiment of the present invention;

[0052] Figure 5 These are schematic diagrams illustrating detailed implementation steps 1 to 2 of the thermal management mode control method provided in this embodiment of the invention.

[0053] Figure 6 These are schematic diagrams illustrating detailed implementation steps 3 to 4 of the thermal management mode control method provided in this embodiment of the invention.

[0054] Figure 7 This is a schematic diagram of the switching relationship of the electric heating management mode according to an embodiment of the present invention. Detailed Implementation

[0055] The thermal management mode control method provided by this invention, and such Figure 2 The electric vehicle thermal management system shown combines various components and their states as preconditions and triggers to switch the thermal management mode. It controls the refrigerant circuit module in the cab, the refrigerant circuit in the battery pack, and the cooling water circulation module in the battery pack through control parameters. The cab refrigerant circuit module includes a solenoid valve, HVAC, condenser, electric compressor, and air conditioning fan. The compressor speed needs to be adjusted according to different cooling modes. The HVAC system provides cab cooling and includes an evaporator, APTC, mode motor, blower box, internal and external circulation motors, and other components. The solenoid valve controls which refrigerant circuit in the cab is normally open; when closed, the cab cannot be cooled. The battery pack refrigerant circuit includes a chiller, electronic expansion valve, and PT sensor. The chiller is where the refrigerant exchanges heat with the battery circulating water, cooling the battery circulating water circuit. The electronic expansion valve is internally controlled by a four-wire stepper motor, adjusting the opening by regulating the number and length of step pulses. The PT sensor collects the pressure and temperature of the refrigerant at the chiller outlet and detects low pressure to provide low-pressure protection for the compressor. The battery pack cooling water circulation module includes a water pump, an expansion tank, and temperature sensors (T1, T2). The expansion tank is responsible for venting and replenishing water. This invention collects the real-time status of each of these components and formulates control commands for each component to ensure the efficient and stable operation of the entire battery thermal management system.

[0056] The specific implementation of the present invention will now be described in detail with reference to the accompanying drawings.

[0057] like Figure 1 As shown, the electric vehicle thermal management mode control method provided by the present invention includes the following steps:

[0058] Step S100: Obtain the device status and environmental parameters of the electric vehicle;

[0059] The thermal management mode control method provided by this invention is implemented based on a TMS controller (hereinafter referred to as the controller), such as... Figure 3As shown, the controller acquires status and parameter values ​​from the water temperature sensor, PT sensor, three-state pressure sensor, compressor, and BMS (Battery Management System), and outputs control commands to the electric water pump, electric fan, solenoid valve, and electronic expansion valve. The specific components involved include: motor, compressor, condenser, fan, chamber, chiller heat exchanger, temperature sensor, pressure sensor, electronic expansion valve, solenoid valve, expansion valve, evaporator, return air and fresh air system, water pump, liquid cooling plate, and battery pack.

[0060] This invention classifies the state values ​​and parameter values ​​of devices:

[0061] On the one hand, the status of the auxiliary drive relay, the status of the PT pressure sensor, the three-state pressure switch, and the compressor status are classified as device statuses to determine the TMS status;

[0062] On the other hand, some device parameter values ​​are extracted from the involved devices and defined as environmental parameters, such as... Figure 4 The parameters shown include: PTC switch position, key position, AC switch, cabin temperature, chiiller outlet temperature (also known as heat exchanger outlet temperature), and peak power of the maximum available discharge of the BMS. These environmental parameters are used to determine the conditions for executing thermal management modes and to switch modes.

[0063] Regarding the acquisition of environmental parameters, sensors are installed at the air supply duct of the fresh air handling unit. These sensors can adjust the temperature based on the difference between the fresh air temperature and the set temperature to achieve constant temperature output, thus improving the comfort of using the fresh air handling unit. A three-state pressure switch is installed at the condenser outlet to protect the compressor from damage when there is a leak in the air conditioning system or when the refrigerant is low. When the condensing pressure is too high, the high pressure is reduced to increase the cooling effect. When the system pressure is too high, the compressor control circuit is cut off to ensure the safety of the air conditioning system.

[0064] Step S110: Determine the TMS status based on the device status;

[0065] Specifically, such as Figure 5 As shown in step one, the TMS state that can be output based on the device status is TMS ready state and TMS not ready state; in each TMS state, the controller specifies that each element executes a different control scheme.

[0066] In this invention, the control scheme refers to the control commands output by the controller to various devices. The content of the control commands includes at least: control timing, solenoid valve operation, water pump speed, electronic expansion valve operation, compressor speed, air conditioner fan speed and duty cycle adjustment, etc. Different control schemes are defined in different states and thermal management modes. The control timing includes the running time, such as the timing of running for 3 seconds or 5 seconds, which is the default when starting up.

[0067] Determining the TMS status based on the device status specifically includes:

[0068] 1. The controller enters the "TMS Not Ready State" when any one of the following four conditions is met:

[0069] 1) The auxiliary drive relay (PDU) is in the off state, that is, the signal value corresponding to message 0x0CFFE3A0 is 0x0 (off);

[0070] 2) In a three-state pressure switch, the high and low pressure side switches are in the open state, i.e., high pressure protection;

[0071] 3) The compressor suction port pressure is low, low pressure protection, that is, the pressure value in the PT pressure sensor is <0.15Mpa;

[0072] 4) The compressor is faulty.

[0073] When it is determined that the electric vehicle is not ready by the TMS, the control scheme to be executed by the controller is the original state control scheme, such as... Figure 5 As shown in the control parameter output section of step two, the compressor speed, water pump, solenoid valve, electronic expansion valve, and air conditioning fan are controlled by commands. The specific original state control scheme is as follows: control commands for each device to return to its original state include: ① Compressor stops. If the compressor speed is greater than 6000 rpm, two stop commands need to be sent. The first command adjusts the compressor speed to 6000 rpm, and the second command sends a complete stop command when the compressor speed is lower than 6000 rpm; ② Water pump stops, 0% duty cycle; ③ Air conditioning fan turns off; ④ Electronic expansion valve turns off; ⑤ Solenoid valve turns on.

[0074] 2. The controller enters the "TMS Ready State" when all four of the following conditions are met:

[0075] 1) The auxiliary drive relay (PDU) is in the closed state, that is, the signal value corresponding to message 0x0CFFE3A0 is 0x1 (closed);

[0076] 2) In a three-state pressure switch, the high and low pressure side switches are in the ON state, meaning there is no high pressure protection;

[0077] 3) The pressure of the PT sensor at the compressor intake port is within the normal range, i.e., the pressure value in the PT pressure sensor is ≥0.15Mpa;

[0078] 4) No compressor fault (0x18FF7919 is identified through compressor message, corresponding signals include compressor operating status, compressor fault level, over-temperature fault, abnormal speed fault, out-of-step fault, overload fault, power tube fault, overcurrent, operating overvoltage, operating undervoltage, standby overvoltage, standby undervoltage, communication fault, overcurrent frequency reduction, overpower frequency reduction, stall fault, phase current sensor fault, over-temperature, and over-temperature frequency reduction);

[0079] Once the TMS is ready, step S120, determining the vehicle's operating status, can be performed.

[0080] Step S120 is used to determine the vehicle status based on the TMS status and device status; the vehicle status includes standby status, charging status and driving status;

[0081] When the TMS status is TMS ready, the vehicle operation conditions are determined based on the device status:

[0082] 1. The controller enters "standby mode" when any one of the following four trigger conditions is met:

[0083] 1) Charging gun connection is invalid;

[0084] 2) DC-DC disconnected;

[0085] 3) The BMS battery pack current is positive.

[0086] 4) The vehicle is in a state where the high voltage is not ready.

[0087] In standby mode, the controller's control scheme is specified as the component check control scheme, such as... Figure 6 As shown in the control parameter notification section of step three, in this state, check the status of components such as the compressor, water pump, and solenoid valve, specifically including: ① compressor stopped; ② water pump stopped, 0% duty cycle; ③ air conditioner fan off; ④ electronic expansion valve closed; ⑤ solenoid valve open.

[0088] 2. The controller enters the "charging state" when all three of the following conditions are met:

[0089] 1) The charging gun is connected to the CC2 signal and the connection is valid;

[0090] 2) The BMS battery pack current is negative;

[0091] 3) Enable the DC-DC operating status signal.

[0092] 3. When the vehicle is in the driving Ready state (the high voltage of the vehicle driving Ready state is: 0x1: Ready), the controller enters the "driving state".

[0093] In charging and driving states, such as Figure 6 As shown in the mode switching condition judgment section of step three, the controller can enter the operation of step S130 to extract device status and environmental parameters, and determine the thermal management mode and mode switching.

[0094] Step S130: Determine whether the electric vehicle has entered thermal management mode based on the driving status.

[0095] When the vehicle is in driving or charging mode, it can enter thermal management mode and switch thermal management modes based on environmental parameters.

[0096] If the vehicle enters thermal management mode, the system determines the most suitable thermal management mode for the electric vehicle based on environmental parameters, specifies the control scheme for the controller according to the thermal management mode, and sends control commands to various components of the electric vehicle.

[0097] The environmental parameters in this invention include standard states, such as: PTC switch not pressed and PTC switch pressed, key position on and key position not on, AC switch active and AC switch inactive; including: standard values ​​for cockpit temperature, standard values ​​for chiillery outlet temperature, and standard values ​​for the peak power of the maximum usable discharge of the BMS.

[0098] For other environmental standard values, such as: cockpit temperature standard value, chiiller outlet temperature standard value, and peak power standard value of maximum usable discharge of BMS;

[0099] Furthermore, to enhance the impact of cockpit temperature and chiillery outlet temperature on thermal management modes, this invention defines the following based on the above standard values:

[0100] The standard value for cockpit temperature also includes a second standard value for cockpit temperature, and the standard value for chiiller outlet temperature also includes a second standard value for chiiller outlet temperature, a third standard value for chiiller outlet temperature, and a fourth standard value for chiiller outlet temperature; and the second standard value for cockpit temperature is defined to be less than the standard value for cockpit temperature; the second standard value for chiiller outlet temperature is defined to be greater than the standard value for chiiller outlet temperature, the fourth standard value for chiiller outlet temperature is defined to be less than the standard value for chiiller outlet temperature, and the third standard value for chiiller outlet temperature is defined to be less than the fourth standard value for chiiller outlet temperature.

[0101] In the embodiments provided by this invention, the above standard values ​​are specifically defined as follows:

[0102] The standard value for cockpit temperature is 26℃, and the second standard value for cockpit temperature is 22℃.

[0103] The standard value for chiller outlet temperature is 16℃, the second standard value for chiller outlet temperature is 20℃, the third standard value for chiller outlet temperature is 12℃, and the fourth standard value for chiller outlet temperature is 14℃.

[0104] The standard value for the peak power of the maximum usable discharge of the BMS (30s) is 30kW.

[0105] Based on the above rules, the environmental parameter conditions are defined as follows:

[0106] 1) The PTC switch is not pressed (VCU_PTC_Switch=0);

[0107] 2) The PTC switch is pressed (VCU_PTC_Switch=1);

[0108] 3) Key position is on (VCU_KeyPosition=1);

[0109] 4) Key position not engaged (VCU_KeyPosition = 0);

[0110] 5) AC switch is valid (the following conditions must be met simultaneously: 1. AC button on the panel is pressed; 2. Temperature control switch is turned on; 3. Fan speed is not 0, and the switch is turned on).

[0111] 6) AC switch is invalid;

[0112] 7) The cockpit temperature is greater than the standard cockpit temperature value, i.e., >26℃;

[0113] 8) The cockpit temperature is less than or equal to the standard cockpit temperature value, i.e., T <= 26℃;

[0114] 9) The cockpit temperature is greater than or equal to the second standard value of cockpit temperature, i.e., T>=22℃;

[0115] 10) The cockpit temperature is less than the second standard value for cockpit temperature, i.e., T < 22℃;

[0116] 11) The outlet temperature of the chiiller is greater than or equal to the standard value of the outlet temperature of the chiiller, that is, T2>=16℃;

[0117] 12) The outlet temperature of the chiiller is less than the standard value of the outlet temperature of the chiiller, that is, T2 < 16℃;

[0118] 13) The outlet temperature of the chiiller is greater than or equal to the second standard value of the outlet temperature of the chiiller, that is, T2>=20℃;

[0119] 14) The outlet temperature of the chiiller is less than the second standard value of the outlet temperature of the chiiller, that is, T2 < 20℃;

[0120] 15) The outlet temperature of the chiiller is greater than the third standard value of the outlet temperature of the chiiller, that is, T2>12℃;

[0121] 16) The outlet temperature of the chiiller is less than or equal to the third standard value of the outlet temperature of the chiiller, that is, T2 <= 12℃;

[0122] 17) The outlet temperature of the chiiller is less than or equal to the fourth standard value of the outlet temperature of the chiiller, that is, T2 <= 14℃;

[0123] 18) The outlet temperature of the chiiller is greater than the fourth standard value of the outlet temperature of the chiiller, that is, T2>14℃;

[0124] 19) The peak power of the maximum usable discharge of the BMS (30S) is greater than or equal to 30kW;

[0125] 20) The peak power of the maximum usable discharge of the BMS (30S) is <30kW.

[0126] This invention fully considers the different cooling needs under various operating conditions and environments. To allocate energy more rationally and improve thermal management efficiency, it refines the energy distribution strategy and formulates the most suitable thermal management modes for various environmental combinations, including: battery pack initial shutdown, battery pack cooling, battery pack temporary shutdown, and battery pack self-circulation. These four thermal management modes are determined solely by heat exchange with the refrigerant cooled by the condenser, and are battery pack-only thermal management modes.

[0127] In practical applications, there is a problem of mutual interference between the cooling intensity of the battery pack and the cooling intensity of the cockpit. If the cooling of the cockpit and the cooling of the battery pack are not decoupled, the mode switching of one will affect the cooling effect of the other. Therefore, this invention proposes a parallel connection between the battery pack cooling and the cockpit cooling, including: cockpit cooling and initial shutdown of the battery pack, cockpit cooling and battery pack cooling, cockpit cooling and temporary shutdown of the battery pack, and cockpit cooling and battery pack self-circulation. These four thermal management modes are cockpit-related thermal management modes.

[0128] This invention decouples the cockpit cooling mode from the various battery pack modes, and promptly adjusts for mutual interference caused by mode switching:

[0129] The cockpit cooling system includes not only condenser cooling but also evaporator cooling. An expansion valve is added to the cockpit cooling circuit, and an electronic expansion valve is added to the battery pack cooling circuit to control the opening. This ensures that the refrigerant flow rate remains regulated during the instantaneous change of cooling demand, thereby buffering sudden changes in cooling intensity and ensuring cooling effect and comfort.

[0130] Meanwhile, to ensure anti-interference capability, the present invention sets the air conditioning fan speed and duty cycle at the condenser and sets an electronic expansion valve at the chiller inlet. This not only effectively regulates the refrigerant temperature but also controls the flow rate of the refrigerant and battery pack fluid heat exchange, so that even when switching between different modes, the different cooling needs of the cockpit and the battery pack will not interfere with each other.

[0131] The present invention, which combines environmental parameters with thermal management modes and control schemes, is described below:

[0132] When environmental parameters meet the following conditions: PTC switch not pressed, key on, and AC switch active, the thermal management mode is related to cab cooling. In this thermal management mode, one or more control schemes are specified for the controller, including:

[0133] The cab cooling and battery pack initial shutdown corresponding to the cab cooling and battery pack initial shutdown control scheme;

[0134] The cab cooling and battery pack cooling corresponding to the cab cooling and battery pack cooling include a first control scheme, a second control scheme, a third control scheme, and a fourth control scheme.

[0135] The cab cooling and battery pack temporary shutdown includes a first control scheme for cab cooling and battery pack temporary shutdown and a second control scheme for cab cooling and battery pack temporary shutdown;

[0136] The cab cooling and battery pack self-circulation system includes a first control scheme for cab cooling and battery pack self-circulation and a second control scheme for cab cooling and battery pack self-circulation.

[0137] When environmental parameters meet the following conditions: PTC switch is pressed, key is not engaged, and AC switch is inactive, the thermal management mode is unrelated to cab cooling. In this thermal management mode, one or more control schemes are still specified for the controller, including:

[0138] The battery pack initial state shutdown includes a first control scheme for battery pack initial state shutdown and a second control scheme for battery pack initial state shutdown;

[0139] The battery pack cooling includes a first control scheme for battery pack cooling, a second control scheme for battery pack cooling, and a third control scheme for battery pack cooling.

[0140] The temporary shutdown of the battery pack includes a first control scheme for temporary shutdown of the battery pack and a second control scheme for temporary shutdown of the battery pack.

[0141] The battery pack self-circulation includes a first control scheme for battery pack self-circulation and a second control scheme for temporary shutdown of the battery pack.

[0142] The above thermal management modes and control schemes are switched and triggered under certain parameter and environmental conditions, and the switching relationship is as follows: Figure 7 The specific switching conditions and control schemes are explained in detail below:

[0143] 1. Cab cooling and battery pack initial shutdown:

[0144] When the thermal management mode is the initial shutdown of the battery pack, the controller enters the cab cooling and battery pack initial shutdown mode under the following conditions: the cabin temperature T1>26℃, the chiller outlet temperature T2<16℃, the peak power of the maximum available discharge of the BMS (30S)≥30kW, the PTC switch is not pressed, the key is in the ON position, and the AC switch is effective.

[0145] In this mode, the output control scheme is the cab cooling and battery pack initial shutdown control scheme, which specifically includes: when starting up, the solenoid valve is opened, the water pump speed is set to 1000 rpm, the electronic expansion valve is 0 opening, and the electric fan runs at a medium-high speed with a duty cycle of 70%; after running for 5 seconds, the compressor speed is set to 1500 rpm; after running for 10 seconds, the compressor speed is increased to 3000 rpm.

[0146] 2. Cab cooling and battery pack cooling:

[0147] 1) When the thermal management mode is battery pack self-circulation, the following conditions must be met: cab temperature T1>26℃, chiller outlet temperature T2≥20℃, peak power of maximum available discharge of BMS (30S)≥30kW, PTC switch not pressed, key in ON position, and AC switch effective. Then the cab cooling and battery pack cooling modes can be switched.

[0148] In this mode, the output control scheme is the first control scheme for cab cooling and battery pack cooling, specifically including: during switching, the water pump speed is set to 1000 rpm, the air conditioning fan runs at full speed with a duty cycle of over 90%, the electronic expansion valve opening is set to 0, and the solenoid valve is opened; after running for 5 seconds, the compressor speed is set to 1500 rpm; after running for another 10 seconds, the compressor speed is increased to 3000 rpm, the electronic expansion valve is set to 17.67% opening, the water pump is set to full speed, and the compressor speed is increased to 5000 rpm; after running for another 10 seconds, the compressor speed is increased to 7000 rpm; after running for another 40 seconds, the electronic expansion valve adjustment is automatically adjusted according to the PT strategy.

[0149] 2) When the thermal management mode is the initial shutdown of the battery pack, the following conditions must be met: cab temperature T1>26℃, chiller outlet temperature T2≥16℃, peak power of maximum usable discharge of BMS (30S)≥30kW, PTC switch not pressed, key in ON position, and AC switch effective. Then the mode can be switched to cab cooling and battery pack cooling.

[0150] In this mode, the output control scheme is the second control scheme for cab cooling and battery pack cooling, which specifically includes: the compressor speed is set to 5000rpm, the water pump is set to full speed, the air conditioning fan runs at full speed with a duty cycle of more than 90%, the electronic expansion valve is set to 17.67% opening, and the solenoid valve is opened; after running for 10 seconds, the compressor speed is increased to 7000rpm; after running for another 40 seconds, the electronic expansion valve is automatically adjusted according to the PT strategy.

[0151] 3) When the thermal management mode is battery pack cooling, the following conditions must be met: cab temperature T1>26℃, chiller outlet temperature T2>12℃, peak power of maximum available discharge of BMS (30S)≥30kW, PTC switch not pressed, key in ON position, and AC switch effective. Then the mode can be switched to cab cooling and battery pack cooling.

[0152] In this mode, the output control scheme is as follows: a third control scheme for cab cooling and battery pack cooling, specifically: the water pump is set to full speed, the air conditioning fan operates at full speed with a duty cycle of over 90%, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened; after running for 5 seconds, the compressor speed is set to 1500 rpm; after running for another 10 seconds, the compressor speed is increased to 3000 rpm, the water pump remains at full speed, the electronic expansion valve is set to 17.67% opening, and the compressor speed is increased to 5000 rpm; after running for another 10 seconds, the compressor speed is increased to 7000 rpm; after running for another 40 seconds, the electronic expansion valve is automatically adjusted according to the PT strategy.

[0153] 4) When the PTC switch is not pressed, the key is in the ON position, and the AC switch is active: If the thermal management mode is cab cooling and battery pack initial shutdown, and the cab temperature T1 ≥ 22℃, the chiiller outlet temperature T2 ≥ 16℃, and the peak power of the maximum available discharge of the BMS (30S) ≥ 30kW, or if the thermal management mode is cab cooling and battery pack self-circulation, and the cab temperature T1 ≥ 22℃, the chiiller outlet temperature T2 ≥ 20℃, and the peak power of the maximum available discharge of the BMS (30S) ≥ 30kW, then the cab cooling and battery pack cooling modes can be switched.

[0154] In this mode, the output control scheme is the fourth control scheme for cab cooling and battery pack cooling, specifically: the compressor speed is set to 7000rpm, the water pump is set to full speed, the air conditioning fan runs at full speed with a duty cycle of more than 90%, the electronic expansion valve is set to 17.67% opening, and the solenoid valve is opened; after running for 40 seconds, the electronic expansion valve is automatically adjusted according to the PT strategy.

[0155] 3. Temporary shutdown of cab cooling and battery pack:

[0156] 1) When the PTC switch is not pressed, the key is in the ON position, and the AC switch is valid, if the thermal management mode is cab cooling and battery pack cooling, and the cab temperature T1≥22℃, the chiiller outlet temperature T2≤12℃, and the peak power of the maximum available discharge of the BMS (30S)≥30kW, or the thermal management mode is battery pack cooling, and the cab temperature T1>26℃, the chiiller outlet temperature T2≤12℃, and the peak power of the maximum available discharge of the BMS (30S)≥30kW, the cab cooling and battery pack temporary shutdown can be switched.

[0157] In this mode, the output control scheme is the first control scheme for cab cooling and temporary battery pack shutdown, which specifically includes: the compressor speed is set to 5000 rpm, the water pump speed is set to 1000 rpm, the air conditioning fan runs at a medium-high speed with a 70% duty cycle, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened; after running for 10 seconds, the air conditioning fan continues to run at a medium-high speed with a 70% duty cycle.

[0158] 2) When the thermal management mode is battery pack temporary shutdown, the following conditions must be met: cab temperature T1>26℃, chiller outlet temperature T2≤14℃, peak power of maximum available discharge of BMS (30S)≥30kW, PTC switch not pressed, key in ON position, and AC switch effective. Then the mode can be switched to cab cooling and battery pack temporary shutdown.

[0159] In this mode, the output control scheme is the second control scheme for cab cooling and temporary battery pack shutdown, specifically: the water pump speed is set to 1000 rpm, the air conditioning fan runs at a medium-high speed with a 70% duty cycle, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened; after running for 5 seconds, the compressor speed is set to 1500 rpm; the air conditioning fan continues to run at a medium-high speed with a 70% duty cycle, and the compressor speed is increased to 3000 rpm;

[0160] 4. Cab cooling and battery pack self-circulation

[0161] 1) When the PTC switch is not pressed, the key is in the ON position, and the AC switch is effective, if the thermal management mode is temporary shutdown of the battery pack, and the cockpit temperature T1 > 26°C, the chiller outlet temperature 14 < T2 < 20°C, and the peak power of the maximum available discharge of the BMS (30S) ≥ 30kW, or if the thermal management mode is self-circulation of the battery pack, and the cockpit temperature T1 > 26°C, the chiller outlet temperature 14 < T2 < 20°C, and the peak power of the maximum available discharge of the BMS (30S) ≥ 30kW, it can be switched to cab refrigeration and self-circulation of the battery pack;

[0162] In this mode, the output control scheme is the first control scheme for cab refrigeration and self-circulation of the battery pack, specifically: the compressor speed is set to 3000 rpm, the water pump is set to full speed rotation, the air-conditioning fan rotates at medium and high speed with a 70% duty cycle, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened;

[0163] 2) When the thermal management mode is cab refrigeration and temporary shutdown of the battery pack, the following conditions: the cockpit temperature T1 ≥ 22°C, the chiller outlet temperature 14 < T2 < 20°C, the peak power of the maximum available discharge of the BMS (30S) ≥ 30kW, the PTC switch is not pressed, the key is in the ON position, and the AC switch is effective are all satisfied, it can be switched to cab refrigeration and self-circulation of the battery pack;

[0164] In this mode, the output control scheme is the second control scheme for cab refrigeration and self-circulation of the battery pack, specifically: the water pump is set to full speed rotation, the air-conditioning fan rotates at medium and high speed with a 70% duty cycle, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened; after running for 5S, the compressor speed is set to 1500 rpm; after running for another 10S, the compressor speed is increased to 3000 rpm.

[0165] 5. Initial shutdown of the battery pack:

[0166] 1) When the controller is in the standby state, it runs for 5 seconds and can be switched to the initial shutdown of the battery pack;

[0167] In this mode, the output control scheme is the first control scheme for the initial shutdown of the battery pack, specifically the compressor speed is set to 0 rpm, the water pump speed is set to 1000 rpm, the air-conditioning fan speed and duty cycle are both set to 0, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened;

[0168] 2) When the thermal management mode is cab refrigeration and initial shutdown of the battery pack, when the condition that the chiller outlet temperature T2 < 16°C, and any one of the conditions that the cockpit temperature T1 < 22°C, the peak power of the maximum available discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF position, and the AC switch is ineffective is satisfied, it can be switched to the initial shutdown of the battery pack;

[0169] In this mode, the control scheme is the second control scheme for the initial shutdown of the battery pack, which is as follows: the compressor speed is set to 0 rpm, the water pump speed is set to 1000 rpm, the air conditioner fan speed and duty cycle are both set to 0, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened.

[0170] 6. Battery pack cooling

[0171] 1) The thermal management mode is cab cooling and battery pack cooling. When any of the following conditions are met, the battery pack cooling mode can be switched to: chiller outlet temperature T2>12℃, cab temperature T1<22℃, peak power of maximum available discharge of BMS (30S)<30kW, PTC switch pressed, key in OFF position, AC switch inactive.

[0172] At this time, the output control scheme is the battery pack cooling first control scheme, specifically: the water pump is set to full speed, the electric fan runs at medium-high speed with a 70% duty cycle, the electronic expansion valve is set to 17.67% opening, and the solenoid valve is closed; after running for 5 seconds, the compressor speed is set to 3000 rpm; after running for another 10 seconds, the compressor speed is increased to 6000 rpm; after running for another 30 seconds, the air conditioning fan maintains a medium-high speed with a 70% duty cycle, and the electronic expansion valve is automatically adjusted according to the PT strategy;

[0173] 2) The thermal management mode is battery pack initial shutdown. When any of the following conditions are met, the battery pack can be switched to cooling mode: the chiller outlet temperature T2 ≥ 16℃, the cockpit temperature T1 ≤ 26℃, the peak power of the maximum usable discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF position, and the AC switch is inactive. Alternatively, the thermal management mode is battery pack self-circulation. When any of the following conditions are met, the battery pack can be switched to cooling mode: the chiller outlet temperature T2 ≥ 20℃, the cockpit temperature T1 ≤ 26℃, the peak power of the maximum usable discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF position, and the AC switch is inactive.

[0174] At this time, the output control scheme is the second control scheme for battery pack cooling, specifically: the compressor speed is set to 6000rpm, the water pump is set to full speed, the air conditioner fan runs at a medium-high speed with a 70% duty cycle, the electronic expansion valve is set to 17.67% opening, and the solenoid valve is closed; after running for another 30 seconds, the air conditioner fan continues to run at a medium-high speed with a 70% duty cycle, and the electronic expansion valve is automatically adjusted according to the PT strategy.

[0175] 3) The thermal management mode is cab cooling and battery pack initial shutdown. When any one of the following conditions is met, the battery pack cooling mode can be switched to: chiller outlet temperature T2≥16℃, cab temperature T1<22℃, peak power of maximum usable discharge of BMS (30S)<30kW, PTC switch pressed, key in OFF position, and AC switch inactive. Alternatively, the thermal management mode is cab cooling and battery pack self-circulation. When any one of the following conditions is met, the battery pack cooling mode can be switched to: chiller outlet temperature T2≥20℃, cab temperature T1<22℃, peak power of maximum usable discharge of BMS (30S)<30kW, PTC switch pressed, key in OFF position, and AC switch inactive.

[0176] At this time, the output control scheme is the third control scheme for battery pack cooling, specifically: the compressor speed is set to 6000rpm, the water pump is set to full speed, the air conditioner fan runs at a medium-high speed with a 70% duty cycle, the electronic expansion valve is set to 17.67% opening, and the solenoid valve is closed; after running for another 30 seconds, the air conditioner fan continues to run at a medium-high speed with a 70% duty cycle, and the electronic expansion valve is automatically adjusted according to the PT strategy.

[0177] 7. Temporary shutdown of battery pack

[0178] 1) The thermal management mode is for both cab cooling and battery pack cooling. When any of the following conditions are met, the battery pack can be temporarily shut down: the chiller outlet temperature T2 ≤ 12℃, the cab temperature T1 < 22℃, the peak power of the maximum usable discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF position, and the AC switch is inactive. Alternatively, the thermal management mode is for battery pack cooling. When any of the following conditions are met, the battery pack can be temporarily shut down: the chiller outlet temperature T2 ≤ 12℃, the cab temperature T1 ≤ 26℃, the peak power of the maximum usable discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF position, and the AC switch is inactive.

[0179] At this time, the output control scheme is the first control scheme for temporary battery pack shutdown, which is as follows: the compressor speed is set to 4000 rpm, the water pump speed is set to 3000 rpm, the air conditioner fan runs at medium to high speed with a 70% duty cycle, and the solenoid valve is opened; after running for 10 seconds, the compressor is turned off; after running for another 10 seconds, the air conditioner fan is turned off.

[0180] 2) The thermal management mode is cab cooling and temporary shutdown of the battery pack, and the conditions are as follows: the temperature T2 at the chiller outlet ≤ 14°C, and the cab temperature T1 < 22°C, the peak power of the maximum available discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF gear position, and the AC switch is ineffective. When any one of these conditions is met, it can be switched to the temporary shutdown of the battery pack;

[0181] At this time, the output control scheme is the second control scheme for the temporary shutdown of the battery pack. Specifically: the compressor speed is set to 0 rpm, the water pump speed is set to 1000 rpm, the air-conditioning fan rotates at medium and high speed with a 70% duty cycle, the electronic expansion valve is set to 0 opening, and the solenoid valve is opened; after running for 10S, the air-conditioning fan is turned off;

[0182] 8. Battery pack self-circulation

[0183] 1) The thermal management mode is the temporary shutdown of the battery pack, and the conditions are as follows: 14 < T2 < 20°C at the chiller outlet, and the cab temperature T1 ≤ 26°C, the peak power of the maximum available discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF gear position, and the AC switch is ineffective. When any one of these conditions is met, it can be switched to the battery pack self-circulation, and the output control scheme is the first control scheme for the battery pack self-circulation;

[0184] 2) The thermal management mode is cab cooling and temporary shutdown of the battery pack. When the conditions are met: 14 < T2 < 20°C at the chiller outlet, and the cab temperature T1 < 22°C, the peak power of the maximum available discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF gear position, and the AC switch is ineffective. When any one of these conditions is met, it can be switched to the battery pack self-circulation; or the thermal management mode is cab cooling and battery pack self-circulation. When the conditions are met: 14 < T2 < 20°C at the chiller outlet, and the cab temperature T1 < 22°C, the peak power of the maximum available discharge of the BMS (30S) < 30kW, the PTC switch is pressed, the key is in the OFF gear position, and the AC switch is ineffective. When any one of these conditions is met, it can be switched to the battery pack self-circulation, and the output control scheme is the second control scheme for the battery pack self-circulation.

[0185] This invention decouples the cockpit cooling mode from the various battery pack modes by controlling the switching between different thermal management modes (i.e., different settings for water pump speed, air conditioning fan speed, electronic expansion valve opening, solenoid valve switch, and compressor speed output at different operating times), thus promptly adjusting for mutual interference caused by mode switching. For example, during the transition from battery pack cooling mode to cockpit cooling mode and back to battery pack cooling mode, the increased cooling demand in the cockpit inevitably leads to a rise in battery pack cooling temperature. If only some parameters (compressor speed and water pump speed) are controlled, the single control of compressor speed and water pump speed cannot meet the decoupling requirement between cockpit thermal management and battery pack thermal management. Therefore, ordinary technical solutions cannot effectively suppress the temperature rise in a timely manner, resulting in significant fluctuations in battery pack cooling temperature.

[0186] This invention improves both the environmental parameter acquisition scheme and the corresponding operation scheme for the thermal management mode. For example, it sets up a system to collect the air conditioning fan speed and duty cycle at the condenser, and an electronic expansion valve at the chiller inlet. This not only effectively regulates the refrigerant temperature but also controls the flow rate of refrigerant-battery pack fluid heat exchange, ensuring that the different cooling needs of the cockpit and battery pack do not interfere with each other even when switching between different modes. For instance, when switching from battery pack cooling mode to cockpit cooling mode and then back to battery pack cooling mode, the increased cooling demand in the cockpit leads to an upward trend in battery pack cooling temperature. In this case, the refrigerant flow rate is increased by increasing the opening of the electronic expansion valve, and the refrigerant temperature is reduced by increasing the air conditioning fan speed and duty cycle, thus effectively lowering the battery pack temperature during refrigerant-battery pack fluid heat exchange.

[0187] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the present invention is not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A method for controlling the thermal management mode of an electric vehicle, characterized in that, include: Obtain the device status and environmental parameters of the electric vehicle; The device status includes: auxiliary drive relay status, PT pressure sensor status, three-state pressure switch, and compressor status; the environmental parameters include: PTC switch position, key position, AC switch, cockpit temperature, chiiller outlet temperature, and peak power of the maximum available discharge of the BMS. The TMS state is determined based on the device state, and the TMS state includes: TMS not ready state and TMS ready state; when the TMS state is TMS not ready, the controller is assigned to execute the original state control scheme. The vehicle status is determined based on the TMS status and device status, and the vehicle status includes standby status, charging status and driving status. Based on the driving status, determine whether the controller has entered thermal management mode. If it has entered thermal management mode, perform thermal management mode switching according to environmental parameters and send control commands corresponding to the control scheme to the electric vehicle device. The thermal management modes include a cab-related thermal management mode and a battery pack-only thermal management mode: the cab-related thermal management modes include: cab cooling and battery pack initial shutdown, cab cooling and battery pack cooling, cab cooling and battery pack temporary shutdown, and cab cooling and battery pack self-circulation; the battery pack-only thermal management modes include: battery pack initial shutdown, battery pack cooling, battery pack temporary shutdown, and battery pack self-circulation. The switching of the thermal management mode includes: The thermal management mode can be switched to cab cooling and battery pack initial shutdown when the battery pack is initially shut down. The output control scheme is the cab cooling and battery pack initial shutdown control scheme. When the thermal management mode is battery pack self-circulation, it can be switched to cab cooling and battery pack cooling, and the output control scheme is the first control scheme for cab cooling and battery pack cooling. The thermal management mode can be switched to cab cooling and battery pack cooling when the battery pack is initially shut down, and the output control scheme is a second control scheme for cab cooling and battery pack cooling. When the thermal management mode is battery pack cooling, it can be switched to cab cooling and battery pack cooling, and the output control scheme is a third control scheme for cab cooling and battery pack cooling. When the thermal management mode is cab cooling and battery pack initial shutdown or cab cooling and battery pack self-circulation, it can be switched to cab cooling and battery pack cooling, and the output control scheme is the fourth control scheme for cab cooling and battery pack cooling. When the thermal management mode is cab cooling and battery pack cooling or battery pack cooling, it can be switched to cab cooling and battery pack temporary shutdown. The output control scheme is the first control scheme for cab cooling and battery pack temporary shutdown. The thermal management mode can be switched to cab cooling and battery pack temporary shutdown when the battery pack is temporarily shut down. The output control scheme is the second control scheme for cab cooling and battery pack temporary shutdown. When the thermal management mode is a temporary shutdown of the battery pack or a self-circulation of the battery pack, it can be switched to cab cooling and battery pack self-circulation. The output control scheme is the first control scheme of cab cooling and battery pack self-circulation. The thermal management mode can be switched to cab cooling and battery pack self-circulation when the cab cooling and battery pack are temporarily stopped. The output control scheme is the second control scheme for cab cooling and battery pack self-circulation.

2. The control method according to claim 1, characterized in that, Before switching the thermal management mode based on environmental parameters, the standard values ​​of the environmental parameters are defined, including: standard value of cockpit temperature, standard value of chiillery outlet temperature, and standard value of peak power of maximum available discharge of BMS. The standard value for cockpit temperature also includes a second standard value for cockpit temperature, and the standard value for chiiller outlet temperature also includes a second standard value for chiiller outlet temperature, a third standard value for chiiller outlet temperature, and a fourth standard value for chiiller outlet temperature.

3. The control method according to claim 2, characterized in that, The second standard value for cockpit temperature is defined as being less than the standard value for cockpit temperature; The second standard value of the chiller outlet temperature is defined as being greater than the standard value of the chiller outlet temperature, the fourth standard value of the chiller outlet temperature is defined as being less than the standard value of the chiller outlet temperature, and the third standard value of the chiller outlet temperature is defined as being less than the fourth standard value of the chiller outlet temperature.

4. The control method according to claim 1, characterized in that, When the environmental parameters meet the following conditions: PTC switch not pressed, key on, AC switch active, the controller can switch to the cab-related thermal management mode and assign one or more control schemes to the controller, including: The cab cooling and battery pack initial shutdown corresponding to the cab cooling and battery pack initial shutdown control scheme; The cab cooling and battery pack cooling corresponding to the cab cooling and battery pack cooling include a first control scheme, a second control scheme, a third control scheme, and a fourth control scheme. The cab cooling and battery pack temporary shutdown includes a first control scheme for cab cooling and battery pack temporary shutdown and a second control scheme for cab cooling and battery pack temporary shutdown; The cab cooling and battery pack self-circulation system includes a first control scheme for cab cooling and battery pack self-circulation and a second control scheme for cab cooling and battery pack self-circulation.

5. The control method according to claim 4, characterized in that, When the environmental parameters meet the following conditions: PTC switch is pressed, key is not engaged, and AC switch is inactive, the controller can switch to battery pack-only thermal management mode and assign one or more control schemes to the controller, including: The initial shutdown of the battery pack includes a first control scheme for the initial shutdown of the battery pack and a second control scheme for the initial shutdown of the battery pack. The battery pack cooling includes a first control scheme for battery pack cooling, a second control scheme for battery pack cooling, and a third control scheme for battery pack cooling. The temporary shutdown of the battery pack includes a first control scheme for temporary shutdown of the battery pack and a second control scheme for temporary shutdown of the battery pack. The battery pack self-circulation includes a first control scheme for battery pack self-circulation and a second control scheme for temporary shutdown of the battery pack.

6. The control method according to claim 4, characterized in that, The switching of the thermal management mode also includes: When the thermal management mode is used for cab cooling and battery pack initial shutdown, it can be switched to battery pack initial shutdown, and the output control scheme is the second control scheme for battery pack initial shutdown. When the thermal management mode is cab cooling and battery pack cooling, it can be switched to battery pack cooling, and the output control scheme is the first control scheme for battery pack cooling. When the thermal management mode is the battery pack initial shutdown or battery pack self-circulation, it can be switched to battery pack cooling, and the output control scheme is the second control scheme for battery pack cooling. When the thermal management mode is cab cooling and battery pack initial shutdown or cab cooling and battery pack self-circulation, it can be switched to battery pack cooling, and the output control scheme is the third control scheme for battery pack cooling. The thermal management mode is cab cooling and battery pack cooling or battery pack cooling. When the battery pack is cooling, it can be switched to battery pack temporary shutdown. The output control scheme is the first control scheme for battery pack temporary shutdown. When the thermal management mode is used for cab cooling and battery pack temporary shutdown, it can be switched to battery pack temporary shutdown, and the output control scheme is the second control scheme for battery pack temporary shutdown. The thermal management mode can be switched to battery pack self-circulation when the battery pack is temporarily shut down, and the output control scheme is the first control scheme for battery pack self-circulation. When the thermal management mode is used for cab cooling and temporary battery pack shutdown or cab cooling and battery pack self-circulation, it can be switched to battery pack self-circulation, and the output control scheme is the second control scheme for battery pack self-circulation.

7. The control method according to claim 1, characterized in that, The step of determining whether the controller enters thermal management mode based on the driving status means that when the driving status is driving or charging, the controller enters thermal management mode based on the environmental parameters.

8. The control method according to claim 1, characterized in that, The control scheme refers to the controller output commands, which include: control timing, solenoid valve operation, water pump speed, electronic expansion valve operation, compressor speed, and air conditioner fan speed and duty cycle adjustment.

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