A thermal management control method for a three-source heat pump unit in a vehicle thermal management system

Abstract

The present invention discloses a thermal management control method for a three-source heat pump unit of a whole vehicle thermal management system, comprising: obtaining operating parameters of the three-source heat pump unit of the whole vehicle; controlling and switching the operating mode of the whole vehicle according to the operating parameters and in accordance with the judgment priority of the operating mode of the heat pump unit; wherein the operating modes include a motor-controlled source heat pump operating mode, a battery-source heat pump operating mode, and an air-source heat pump operating mode; the motor-controlled source heat pump operating mode is an operating mode in which excess heat is absorbed from the rotating and power-consuming motor control by operating the compressor; the battery-source heat pump operating mode is an operating mode in which heat is absorbed from the battery cell by operating the compressor; and the air-source heat pump operating mode is an operating mode in which heat is absorbed from the external ambient air by operating the compressor; the technical solution provided by the present invention improves heat utilization, makes a comprehensive judgment based on energy balance and efficiency priority, adjusts the whole vehicle to the optimal operating mode, and improves the working performance of the three-source heat pump unit.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of thermal management of electric vehicles, and in particular to a thermal management control method for a three-source heat pump unit in a thermal management system of a vehicle. Background Art

[0002] The powertrain of new energy vehicles uses a traction motor, a gearbox, a variable frequency drive system for the traction motor, and a four-in-one power control assembly. The entire powertrain of new energy vehicles is referred to as the motor and electronic control. The motor and electronic control is a combination of the engine assembly and the gearbox assembly of a traditional car. It is the heart of the entire car and serves the purpose of dragging the vehicle to operate.

[0003] In the prior art, the motor and electronic control of the vehicle are always pulling and dragging the load vehicle body during operation. Since the motor and electronic control generate a large amount of heat during operation, this heat will be transferred to the flowing ethylene glycol solution in the cooling water jacket in the motor housing. The ethylene glycol solution is driven by the electronic water pump to flow through the radiator water tank, the motor housing cooling water jacket and the pipeline. In the radiator water tank, this part of the heat is released into the environment through the electronic fan, thereby wasting this part of the heat. As a result, in the autumn and winter when the ambient temperature is low, the heating of the air conditioner is relied upon more, which increases the heating load and reduces the cruising range of the vehicle. Summary of the Invention

[0004] The present invention provides a thermal management control method for a three-source heat pump unit in a vehicle thermal management system, which improves heat utilization, makes a comprehensive judgment based on energy balance and efficiency priority, adjusts the vehicle to an optimal operating mode, and improves the working performance of the three-source heat pump unit.

[0005] An embodiment of the present invention provides a thermal management control method for a three-source heat pump unit in a vehicle thermal management system, comprising:

[0006] Obtain the operating parameters of the vehicle's three-source heat pump unit;

[0007] According to the operating parameters and the judgment priority of the operating mode of the heat pump unit, the operating mode of the whole vehicle is controlled and switched; wherein the operating modes include a motor-controlled source heat pump operating mode, a battery-controlled source heat pump operating mode, and an air-source heat pump operating mode; the motor-controlled source heat pump operating mode is an operating mode in which excess heat is absorbed from the rotating and power-consuming motor control by operating the compressor; the battery-controlled source heat pump operating mode is an operating mode in which heat is absorbed from the battery cell by operating the compressor; and the air-source heat pump operating mode is an operating mode in which heat is absorbed from the external ambient air by operating the compressor;

[0008] The judgment priority is as follows: if it is determined that the operation mode of the motor-controlled heat pump is met, then the operation mode of the whole vehicle is controlled to be switched to the motor-controlled heat pump operation mode; if it is determined that the operation mode of the motor-controlled heat pump is not met, then whether the operation mode of the battery-controlled heat pump is met is determined; if it is determined that the operation mode of the battery-controlled heat pump is met, then the operation mode of the whole vehicle is controlled to be switched to the battery-controlled heat pump operation mode;

[0009] If it is determined that it does not comply with the motor-controlled source heat pump operation mode and does not comply with the battery-source heat pump operation mode, then it is determined whether it complies with the air source heat pump operation mode. If it is determined that it complies with the air source heat pump operation mode, then the operation mode of the entire vehicle is controlled to be switched to the air source heat pump operation mode.

[0010] Optionally, the operating parameters include the water outlet temperature of the motor electronic control, the heat dissipation of the motor electronic control, the input power of the compressor, the ambient temperature, and the speed of the compressor; and according to the operating parameters and the priority of the operating mode of the heat pump unit, controlling the switching of the operating mode of the vehicle includes:

[0011] When the three-source heat pump unit is in a standby state, judging whether the initial operating conditions of the motor-controlled source heat pump operation mode are met according to the outlet water temperature of the motor-controlled source heat pump;

[0012] If the initial operating conditions of the motor-controlled heat source operation mode are met, the heating capacity of the motor-controlled heat source pump is determined according to the heat dissipation of the motor-controlled heat source and the input power of the compressor; the heating capacity of the air-source heat pump is determined according to the outlet water temperature of the motor-controlled heat source, the ambient temperature and the speed of the compressor;

[0013] The heating capacity of the motor-controlled heat source pump is compared with the heating capacity of the air source heat pump. If the heating capacity of the motor-controlled heat source pump is greater than the heating capacity of the air source heat pump, the three-source heat pump unit is switched from the standby mode to the motor-controlled heat source pump operation mode.

[0014] Optionally, the operating parameters further include the heating capacity of the battery source heat pump and the battery cell temperature;

[0015] If the initial operating conditions of the motor-controlled heat pump operating mode are not met, determining whether the operating conditions of the battery-source heat pump operating mode are met based on the amount of heat absorbed by the battery-source heat pump from the battery cell, the battery cell temperature, and the ambient temperature;

[0016] Among them, if the battery cell temperature is greater than the minimum temperature for operating the battery-source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air-source heat pump, the heating capacity of the battery-source heat pump is determined according to the heat absorption of the battery-source heat pump from the battery cell and the input power of the compressor; if the heating capacity of the battery-source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery-source heat pump operation mode are met, and the three-source heat pump unit is switched from the standby mode to the battery-source heat pump operation mode.

[0017] Optionally, if the operating conditions of the battery source heat pump operating mode are not met, the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump is judged; if the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump, the three-source heat pump unit is switched from the standby mode to the air source heat pump operating mode.

[0018] Optionally, the operating parameters further include the heating capacity of the battery source heat pump and the battery core temperature;

[0019] The three-source heat pump unit operates in the motor-controlled heat pump operation mode, and the difference between the heat dissipation of the motor-controlled heat source and the heating capacity of the motor-controlled heat source pump is within a preset range. Then, it is determined whether the operating conditions of the battery-source heat pump operation mode are met based on the amount of heat absorbed by the battery-source heat pump from the battery cell, the battery cell temperature, and the ambient temperature.

[0020] Among them, if the battery cell temperature is greater than the minimum temperature for operating the battery-source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air-source heat pump, the heating capacity of the battery-source heat pump is determined according to the heat absorption of the battery-source heat pump from the battery cell and the input power of the compressor; if the heating capacity of the battery-source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery-source heat pump operation mode are met, and the three-source heat pump unit is switched from the motor-controlled source heat pump operation mode to the battery-source heat pump operation mode.

[0021] Optionally, if the operating conditions of the battery source heat pump operating mode are not met, the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump, and the relationship between the heating capacity of the motor-controlled heat source pump and the heating capacity of the air source heat pump are determined;

[0022] If the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump, and the heating capacity of the motor-controlled heat source pump is less than the heating capacity of the air source heat pump, the three-source heat pump unit switches from the motor-controlled heat source pump operation mode to the air source heat pump operation mode.

[0023] Optionally, the three-source heat pump unit operates in the battery-source heat pump operation mode, and determines whether the initial operation conditions of the motor-controlled source heat pump operation mode are met according to the outlet water temperature of the motor electronic control; if so, the three-source heat pump unit switches from the battery-source heat pump operation mode to the motor-controlled source heat pump operation mode;

[0024] If not satisfied, the relationship between the battery cell temperature and the minimum temperature for operating the battery source heat pump, as well as the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump operation mode, are detected; wherein, if the battery cell temperature is lower than the minimum temperature for operating the battery source heat pump, and the ambient temperature is greater than or equal to the minimum ambient temperature for operating the air source heat pump operation mode, the three-source heat pump unit switches from the battery source heat pump operation mode to the air source heat pump operation mode.

[0025] Optionally, the three-source heat pump unit operates in the air source heat pump operation mode. If the outlet water temperature of the motor electronic control is greater than the minimum temperature for operating the motor electronic control source heat pump, the heating capacity of the motor electronic control heat source pump is greater than the heating capacity of the air source heat pump, and the outlet water temperature of the motor electronic control is greater than a preset temperature for a preset time, the three-source heat pump unit switches from the air source heat pump operation mode to the motor electronic control source heat pump operation mode.

[0026] If the heating capacity of the motor-controlled heat source pump is less than the heating capacity of the air-source heat pump, and the outlet water temperature of the motor-controlled heat source pump is less than the preset temperature for a preset time, then judging whether the operating conditions of the battery-source heat pump operating mode are met based on the amount of heat absorbed by the battery-source heat pump from the battery cell, the battery cell temperature, and the ambient temperature;

[0027] Among them, if the battery cell temperature is greater than the minimum temperature for operating the battery-source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air-source heat pump, the heating capacity of the battery-source heat pump is determined according to the heat absorption of the battery-source heat pump from the battery cell and the input power of the compressor; if the heating capacity of the battery-source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery-source heat pump operation mode are met, and the three-source heat pump unit is switched from the air-source heat pump operation mode to the battery-source heat pump operation mode.

[0028] Optionally, the operation mode further includes an air-heating operation mode, and the air-heating operation mode is an air-heating resistance heating mode;

[0029] If the battery cell temperature is lower than the minimum temperature for operating the battery source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air source heat pump, the operation mode of the three-source heat pump unit is switched to the air heating operation mode.

[0030] Optionally, the operating mode also includes a natural heating operating mode. When the outlet water temperature of the motor electronic control is greater than a first preset temperature and there is a heating demand, the operating mode of the three-source heat pump unit is switched to the natural heating operating mode; when the outlet water temperature of the motor electronic control is lower than a second preset temperature, the operating mode of the three-source heat pump unit is switched to the motor electronic control source heat pump operating mode, and the first preset temperature is higher than the second preset temperature.

[0031] The technical solution provided by the embodiment of the present invention determines the operating mode of each priority based on the operating parameters of the heat pump unit, utilizes the three-source heat pump unit to absorb heat from the external ambient air, absorbs excess heat from the rotating and power-consuming motor and electronic control, and absorbs a certain amount of heat from the battery cells, thereby improving the heat utilization rate. Based on a comprehensive judgment based on energy balance and efficiency priority, the entire vehicle is adjusted to the optimal operating mode, thereby improving the working performance of the three-source heat pump unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A flow chart of a thermal management control method for a three-source heat pump unit in a vehicle thermal management system provided by an embodiment of the present invention.

[0033] Figure 2 A flow chart of a method for controlling switching of the operating mode of a vehicle according to the operating parameters and the judgment priority of the operating mode of a heat pump unit provided in an embodiment of the present invention.

[0034] Figure 3 A flowchart of another method for controlling switching of the operating mode of a vehicle according to the operating parameters and the judgment priority of the operating mode of a heat pump unit provided in an embodiment of the present invention.

[0035] Figure 4 A flowchart of another method for controlling switching of the operating mode of a vehicle according to the operating parameters and the judgment priority of the operating mode of a heat pump unit provided in an embodiment of the present invention.

[0036] Figure 5 A flowchart of another method for controlling switching of the operating mode of a vehicle according to the operating parameters and the judgment priority of the operating mode of a heat pump unit provided in an embodiment of the present invention.

[0037] Figure 6 A schematic diagram of a control flow of a heat pump unit in standby mode provided by an embodiment of the present invention.

[0038] Figure 7 A schematic diagram of the control flow of a heat pump unit provided by an embodiment of the present invention when it is in a motor-controlled source heat pump operation mode.

[0039] Figure 8A schematic diagram of the control flow of a heat pump unit provided by an embodiment of the present invention when in a battery source heat pump operation mode.

[0040] Figure 9 A schematic diagram of the control flow of a heat pump unit provided by an embodiment of the present invention when it is in an air source heat pump operation mode.

[0041] Figure 10 A schematic diagram of the system structure of a three-source heat pump unit in a vehicle thermal management system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0043] Figure 1 The following is a flow chart of a thermal management control method for a three-source heat pump unit for a whole vehicle provided by an embodiment of the present invention. This embodiment is applicable to the thermal management of a whole electric vehicle. The method specifically includes the following steps:

[0044] S110, obtaining the operating parameters of the vehicle's three-source heat pump unit;

[0045] Specifically, the operating parameters include various types of data information such as water outlet temperature, battery cell temperature, ambient temperature, heat pump compressor output power, and heat dissipation and heating capacity of the heat pump unit. The above operating parameters can be obtained through hardware, such as distributing sensors at corresponding collection positions for real-time collection, and can also be obtained by performing data statistics and calculations on the obtained operating parameters to obtain summarized operating parameters.

[0046] S120, controlling the switching of the operation mode of the entire vehicle according to the operation parameters and the judgment priority of the operation mode of the heat pump unit;

[0047] Among them, the operating modes include motor-controlled source heat pump operating mode, battery-controlled source heat pump operating mode, and air-source heat pump operating mode; the motor-controlled source heat pump operating mode is an operating mode that absorbs excess heat from the rotating and power-consuming motor control through the operation of the compressor; the battery-controlled source heat pump operating mode is an operating mode that absorbs heat from the battery cell through the operation of the compressor; and the air-source heat pump operating mode is an operating mode that absorbs heat from the external ambient air through the operation of the compressor.

[0048] The judgment priority is as follows: if it is judged that the motor-controlled heat pump operation mode is met, the control switches the operation mode of the entire vehicle to the motor-controlled heat pump operation mode;

[0049] If it is determined that the operation mode does not conform to the motor-controlled heat pump mode, then it is determined whether the operation mode conforms to the battery-controlled heat pump mode. If it is determined that the operation mode conforms to the battery-controlled heat pump mode, then the operation mode of the entire vehicle is switched to the battery-controlled heat pump mode.

[0050] If it is determined that the operation mode does not conform to the motor-source heat pump mode and does not conform to the battery-source heat pump mode, then it is determined whether the operation mode conforms to the air-source heat pump mode. If it is determined that the operation mode conforms to the air-source heat pump mode, then the operation mode of the entire vehicle is switched to the air-source heat pump mode.

[0051] Specifically, the three-source heat pump unit can provide high-temperature hot water supply to the battery and cockpit in the motor-controlled source heat pump operation mode. The typical hot water supply temperature range is 40℃-55℃. The operation modes include motor-controlled source heat pump operation mode, battery-source heat pump operation mode, and air-source heat pump operation mode. They all start the compressor and run the heat pump to absorb heat. Among them, the motor-controlled source heat pump operation mode absorbs excess heat from the rotating and power-consuming motor control, the battery-source heat pump operation mode absorbs a certain amount of heat from the battery cell, and the air-source heat pump operation mode absorbs heat from the external ambient air. All of this heat is low-grade heat with relatively low temperature, which is then raised to high-grade heat with high ambient temperature through the heat pump.

[0052] In terms of heating efficiency, electric motor heat pumps offer high efficiency. Typical operating temperatures on the heat-absorbing side of electric motor heat pumps range from 5 to 35°C. Their cold plate heat transfer efficiency is high, resulting in a high evaporation temperature. Electric motor heat pumps can be defined as water-source heat pumps, operating in a highly efficient heating mode. Regarding their operating range, electric motor heat pumps operate only when the vehicle is starting and the traction motor and controller are operating. The greater the motor output (heavier load, faster speed, and hill climbing), the greater the heat dissipation, and the greater the heat that can be recovered by the electric motor control. In battery-source heat pump operation, battery cell temperatures are maintained, allowing operation in both driving and parking scenarios. However, continuous operation is limited, and the battery cell temperature must be maintained within a relatively narrow and reasonable temperature range. Air-source heat pumps offer the widest operating range, operating in temperatures as low as -15°C or below.

[0053] Through the operating parameters of the three-source heat pump unit, such as the inlet and outlet water temperatures of the motor and electronic control, the water pump speed of the motor and electronic control, the ambient temperature, the battery cell temperature, the operating speed of the compressor, the hot water temperature, the opening of the three-way valve and other parameters, the heating capacity and efficiency of the operating air source heat pump are obtained through calculation; the heat dissipation and heating capacity as well as the efficiency of the motor and electronic control source heat pump are obtained; the heat dissipation and heating capacity, efficiency, available total heating capacity and heating time of the battery source heat pump are obtained, and a comprehensive judgment is made based on energy balance and efficiency priority to determine the operating mode of the entire vehicle.

[0054] Therefore, the priority of judging the operating mode can be as follows: when the vehicle has enough motor heat accumulated during driving, the motor-controlled heat pump mode is prioritized, as it provides sufficient heat in an efficient and stable manner; when the motor-controlled heat pump operating conditions are not met, the battery-controlled heat pump operating mode is prioritized for detection. If so, the battery-controlled heat pump can be prioritized for operation. If not, the air-controlled heat pump operating mode is detected for detection. If so, the air-controlled heat pump operating mode can be prioritized for operation. Exemplarily, the operating mode also includes an air-heating operating mode. If the air-controlled heat pump operating mode is not met, the vehicle can operate in an air-heating operating mode, directly using the air-heating resistor for heating to meet the heating demand.

[0055] The technical solution provided by the embodiment of the present invention determines the operating mode of each priority based on the operating parameters of the heat pump unit, utilizes the three-source heat pump unit to absorb heat from the external ambient air, absorbs excess heat from the rotating and power-consuming motor and electronic control, and absorbs a certain amount of heat from the battery cells, thereby improving the heat utilization rate. Based on a comprehensive judgment based on energy balance and efficiency priority, the entire vehicle is adjusted to the optimal operating mode, thereby improving the working performance of the three-source heat pump unit.

[0056] Figure 2 A flow chart of a method for controlling the switching of the operation mode of a vehicle according to the priority of the operation parameters and the operation mode of the heat pump unit provided by an embodiment of the present invention, see Figure 2 Based on the above embodiment, the operating parameters include the outlet water temperature of the motor electronic control, the heat dissipation of the motor electronic control, the input power of the compressor, the ambient temperature and the speed of the compressor. The method steps include:

[0057] S210: The three-source heat pump unit is in standby mode, and the water outlet temperature of the motor and electronic control is used to determine whether the initial operating conditions of the motor and electronic control source heat pump operation mode are met;

[0058] Specifically, for new energy vehicles, when the vehicle is started, the motor-controlled water pump is in the starting state in both driving and parking scenarios, so as to ensure that the ethylene glycol solution in the motor-controlled cooling channel is flowing. The outlet water temperature of the motor-controlled water is detected. If the outlet water temperature of the motor-controlled water is higher than the minimum temperature T that allows the motor-controlled source heat pump to operate, the motor-controlled water pump is turned off.Min_MSHP_run , and the outlet water temperature of the motor electronic control is increased within a certain period of time. For example, if the outlet water temperature of the motor electronic control is increased by at least 5°C within 2 minutes, it can be explained that most of the vehicle's operating scenarios are in load driving, and the load is moderate or large, and the motor electronic control is in continuous heating. Therefore, it can be judged that the heat pump unit meets the entry operating conditions of the motor electronic control source heat pump operation mode, that is, the initial operating conditions. Among them, the minimum temperature T allowed for the operation of the motor electronic control source heat pump is Min_MSHP_run The value can be adjusted according to the manufacturer and is optional. The typical setting value is 10℃.

[0059] S220: If the initial operating conditions of the motor-controlled heat pump operation mode are met, the heating capacity of the motor-controlled heat pump is determined based on the heat dissipation of the motor and the input power of the compressor; the heating capacity of the air-source heat pump is determined based on the outlet water temperature of the motor, the ambient temperature, and the speed of the compressor;

[0060] Specifically, the water temperature on the heat absorption side of the motor-controlled source heat pump is typically in the range of 5-35°C. Considering that the water-cooled heat exchange performance is relatively efficient, the heat transfer temperature difference is about 3°C. The evaporation temperature on the low-pressure side of the motor-controlled source heat pump is 0-30°C. The evaporation temperature is high and the efficiency is also high. However, the heating capacity of the motor-controlled heat pump mainly depends on the heat dissipation of the motor-controlled heat pump, which is related to various complex factors such as vehicle speed, vehicle load, and vehicle climbing conditions. For example, for a 4x6 heavy truck, under typical flat road conditions, the vehicle speed is 40-60km / h, and the load is at the nominal load, the motor power is about 110kW, and the heat dissipation is about 11kW. Under typical flat road conditions, the vehicle speed is 70-80km / h, the motor power is 180kW, and the heat dissipation is about 18kW. Therefore, the heat dissipation of the motor-controlled heat pump is discrete and does not have much regularity. Therefore, the heat dissipation cannot be calculated by the travel state. In fact, the heat dissipation of the motor-controlled heat pump can be obtained by calculating the water flow through the motor-controlled heat pump and the inlet and outlet water temperatures of the motor-controlled heat pump. Optionally, calculate the heat dissipation of the motor-controlled heat pump:

[0061] Q motor_sp =c P ·q m_motor_sp ΔT motor_water_sp ;

[0062]

[0063] Among them, Q motor_sp is the heat dissipation of the motor electronic control under actual operating conditions; c P is the specific heat capacity of ethylene glycol solution; ΔT motor_water_sp is the temperature difference between the inlet and outlet water of the ethylene glycol solution of the motor electronic control under actual operating conditions; q m_motor_sp is the water flow rate through the motor control; q m_motor_0is the water flow rate when running at full load; Correction for flow rate; Pump flow correction based on the opening degree of the water three-way valve.

[0064] Generally, the design of a motor-controlled heat pump requires setting corresponding operating conditions. For example, the operating conditions of the embodiment of the present invention are set as the inlet water temperature of the motor-controlled heat pump is 15°C and the outlet water temperature of the hot water supply is 45°C. The inlet water temperature range of the motor-controlled heat pump is 5°C-35°C, and the outlet water temperature range is 40°C-55°C. The motor-controlled heat pump absorbs the heat dissipation Q of the motor-controlled heat pump from the motor side. motor_sp , the heat dissipation Q of the motor electronic control through waste heat recovery motor_sp After the heat is improved by the water source heat pump process of the refrigeration system, high-temperature hot water is provided to the cockpit and batteries. The heating capacity of the motor-controlled heat pump is entirely determined by the heat dissipation Q of the motor-controlled heat pump that can be recovered. motor_sp , and the heat dissipation of the motor electronic control is Q motor_sp Depending on various complex factors such as vehicle load, vehicle speed, vehicle climbing conditions, etc., the heat dissipation Q of the recovered motor electronic control can be obtained by calculation. motor_sp The heating capacity of the motor electronically controlled heat source pump is equal to the heat dissipation Q recovered by the motor electronic control motor_sp Add the input power of the compressor, that is:

[0065] Q heat_MSHP_sp =Q motor_sp +P compr_sp ;

[0066] Q heat_MSHP_sp P is the heating capacity of the motor-controlled heat source pump; compr_sp The input power of the compressor is about 24%-28% of the heating capacity of the motor-controlled heat source pump in the actual operating range.

[0067] Among them, the compressor input power can be obtained by calculation. For example, for a three-source heat pump unit with a motor-controlled heat pump heating capacity of 14kW, the design operating conditions are that the inlet water temperature range of the motor-controlled heat pump is 5℃-35℃, and the outlet water temperature range is 40℃-55℃. The prototype is measured to test the compressor input power of the unit. The test data is fitted by a nonlinear data regression method to obtain the correlation formula z=f(y1, y2, y3) with the motor-controlled heat pump compressor input as a function (z), the motor-controlled inlet water temperature (y1), the compressor speed (y1) and the outlet water temperature of the hot water supply (y3) as independent variables. Under actual operating conditions, based on the motor-controlled inlet water temperature, compressor speed, and outlet water temperature of the hot water supply collected by the unit, the compressor input power under this actual operating condition can be calculated as:

[0068]

[0069] in, It is the correction value of the compressor power changing with the compressor speed under actual operating conditions; The correction value of the compressor power under actual operating conditions changes with the inlet water temperature of the motor electronic control It is the correction value of the compressor power changing with the outlet water temperature of the motor electronic control under actual operating conditions.

[0070] in,

[0071]

[0072]

[0073]

[0074] PWM compr_sp PWM is the compressor speed PWM value under actual operating conditions; compr_0 is the PWM value of the compressor speed under the designed operating conditions; T inlet_water_MSHP_sp is the inlet water temperature of heating under actual operating conditions; T inlet_water_motor_sp is the water inlet temperature of the motor electronic control under actual operating conditions. The coefficients in each correction value can be obtained by regression fitting based on the test data under the design conditions.

[0075] Generally, the design of an air source heat pump requires setting corresponding operating conditions. For example, the operating conditions set in the embodiment of the present invention are an ambient temperature of 7°C and a hot water outlet temperature of 45°C. For a three-source heat pump unit with an air source heat pump heating capacity of 14kW, according to the data measured by the prototype, the ambient temperature range is -15°C-20°C, and the outlet water temperature range is 40°C-55°C. The heating capacity of the unit is tested, and the test data is fitted by a nonlinear data regression method to obtain the correlation formula z=f(y1, y2, y3) with the air source heat pump heating capacity as a function (z) and the ambient temperature (y1), the compressor speed (y1) and the hot water outlet temperature (y2) as independent variables. Under actual operating conditions, according to the ambient temperature, compressor speed, and hot water outlet temperature collected by the unit, the heating capacity of the unit under this actual operating condition is calculated as:

[0076]

[0077]

[0078]

[0079]

[0080] Among them, Q heat ASHP_sp Q is the heating capacity of the air source heat pump under actual operating conditions; heat_ASHP_0 To calibrate the heating capacity of the air source heat pump under the operating conditions, for example, the calibration condition is an ambient temperature of 10°C ； T amb is the ambient temperature under actual operating conditions; It is the correction value of the heating amount changing with the compressor speed under actual operating conditions; It is the correction value of heating capacity changing with ambient temperature under actual operating conditions; PWM is the correction value of the heating capacity changing with the hot water temperature under actual operating conditions; compr_sp PWM is the compressor speed PWM value under actual operating conditions; compr_0 is the compressor speed PWM value under the design operating condition. The coefficients in each correction value can be obtained by regression fitting based on the test data under the design operating condition.

[0081] S230: Compare the heating capacity of the motor-controlled heat source pump and the heating capacity of the air-source heat pump. If the heating capacity of the motor-controlled heat source pump is greater than that of the air-source heat pump, the three-source heat pump unit is switched from the standby mode to the motor-controlled heat source pump operation mode.

[0082] Specifically, if the heating capacity of the electric motor heat source pump is greater than that of the air source heat pump, it can be ensured that once the electric motor heat source pump is in operation, the heating capacity of the electric motor heat source pump will be greater than that of the corresponding air source heat pump at the current ambient temperature, and it will be more efficient and last longer. Therefore, the three-source heat pump unit is switched from standby mode to electric motor heat pump operation mode.

[0083] Based on the above embodiment, optionally, the operating parameters further include the heating amount of the battery-source heat pump and the battery core temperature; if the initial operating conditions of the motor-controlled heat pump operating mode are not met, whether the operating conditions of the battery-source heat pump operating mode are met is determined based on the amount of heat absorbed by the battery core by the battery-source heat pump, the battery core temperature, and the ambient temperature;

[0084] Among them, if the battery cell temperature is greater than the minimum temperature T of the battery source heat pump Min_BattHP_run If the ambient temperature is lower than the minimum ambient temperature for the operation of the air source heat pump, the heating capacity of the battery source heat pump is determined according to the heat absorption of the battery cell by the battery source heat pump and the input power of the compressor; if the heating capacity of the battery source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery source heat pump operation mode are met, and the three-source heat pump unit switches from standby mode to battery source heat pump operation mode.

[0085] Specifically, the battery source heat pump absorbs heat from the battery cell, and the amount of heat absorbed by the battery source heat pump is only proportional to the temperature change rate of the battery cell ΔT battIt is directly proportional. Table 1 is a comparison table between the heat absorbed from the battery and the temperature change rate of the battery cell under a typical battery cell design. See Table 1. For example, when the heat absorbed from the battery cell is 10kW, the temperature change rate of the battery cell is 0.254℃ / min. For a 282kWh battery cell, the total weight is about 2360kg.

[0086] The calculation of the compressor input power is similar to that of the motor-controlled heat pump operation mode and can be expressed as:

[0087] Q heat_BattHP_sp =Q batt_heat_sp +P compr_sp ;

[0088] Q heat_BattHP_sp Q is the heating capacity of the battery source heat pump under actual operating conditions; batt_heat_sp P is the amount of heat absorbed from the battery in the battery electric control source heat pump operation mode under actual working conditions; compr_sp It is the compressor input power under actual working conditions.

[0089] The heat absorbed by the battery source heat pump is calculated based on the rate of change of the battery core temperature:

[0090]

[0091]

[0092] ΔT batt / Δt is the temperature reduction rate of the compressor core under actual operating conditions; m batt Total mass of the battery cell; The average specific heat capacity of the battery cell.

[0093] Table 1 is a comparison table between the heat absorbed from the battery and the temperature change rate of the battery cell under typical battery cell designs.

[0094]

[0095] Furthermore, by detecting the battery core temperature at this moment (e.g. 18°C) and the lowest temperature T Min_BattHP_run (typical setting value 12℃) for comparison, the heat that can be absorbed from the battery cell is determined based on the maximum allowable drop in the battery cell temperature. For example, if the maximum allowable drop in the battery cell temperature is 4℃ as heat absorption, if the cabin heating demand is 5kW, the estimated compressor input power is about 25% of the heating capacity, then the heat absorption demand from the battery cell is 3.75kW, then based on The calculation shows that the sustainable heating time is 62 minutes.

[0096] Therefore, according to the above operating parameters, the three-source heat pump unit is in standby state. If it is judged that the initial operating conditions of the motor-controlled source heat pump operation mode are not met, it is judged whether the battery cell temperature is higher than the minimum temperature T for operating the battery source heat pump. Min_BattHP_run , and whether the ambient temperature is lower than the minimum ambient temperature for running the air source heat pump. Min_BattHP_run It is the entry condition for running the battery source heat pump. When the battery cell temperature is higher than the minimum temperature T Min_BattHP_run , and the ambient temperature is lower than the minimum ambient temperature for operating the air source heat pump. At the same time, the heating capacity of the battery source heat pump is greater than the heating standard. For example, within the cycle when the battery core temperature drops from 18°C ​​to 12°C, 5kW of heating capacity can be obtained, and the operating time can be more than 60 minutes. It can be determined that the heating requirements are met by operating according to the 15-minute demand. Therefore, the three-source heat pump unit switches from standby mode to battery source heat pump operation mode.

[0097] Based on the above embodiment, optionally, the three-source heat pump unit is in standby mode. If the operating conditions of the battery source heat pump operation mode are not met, the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump is judged. If the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump, the three-source heat pump unit switches from standby mode to air source heat pump operation mode.

[0098] Specifically, when the three-source heat pump unit is in standby mode, if the initial operating conditions of the motor-controlled source heat pump operation mode are not met, and the operating conditions of the battery-source heat pump operation mode are not met, and if the ambient temperature is greater than the minimum ambient temperature for operating the air-source heat pump, the three-source heat pump unit will switch from standby mode to air-source heat pump operation mode, and directly absorb heat from the environment for heating.

[0099] Figure 3 A flow chart of another method for controlling the switching of the operation mode of the vehicle according to the priority of the operation parameters and the operation mode of the heat pump unit provided by the embodiment of the present invention is shown in FIG. Figure 3 Based on the above embodiment, the operating parameters also include the heating capacity of the battery source heat pump and the battery core temperature. The method steps include:

[0100] S310: When the three-source heat pump unit operates in the motor-controlled heat pump mode, and the difference between the heat dissipation of the motor-controlled heat pump and the heating capacity of the motor-controlled heat source pump is within a preset range, determining whether the operating conditions of the battery-controlled heat pump mode are met based on the amount of heat absorbed by the battery cell, the battery cell temperature, and the ambient temperature;

[0101] S320, if the battery cell temperature is greater than the minimum temperature T of the battery source heat pump Min_BattHP_run, if the ambient temperature is lower than the minimum ambient temperature for the operation of the air source heat pump, the heating capacity of the battery source heat pump is determined according to the heat absorption of the battery cell by the battery source heat pump and the input power of the compressor; if the heating capacity of the battery source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery source heat pump operation mode are met, and the three-source heat pump unit switches from the motor-controlled source heat pump operation mode to the battery source heat pump operation mode.

[0102] Specifically, the current three-source heat pump unit operates in the motor-controlled source heat pump operation mode. For example, in order to prevent the frequent switching of the motor-controlled source heat pump operation mode, the lowest temperature T Min_MSHP_run Subtract the preset temperature as the entry judgment condition for mode switching, and detect whether the outlet water temperature of the motor electronic control is lower than the minimum temperature T of the motor electronic control source heat pump. Min_MSHP_ran Subtract the preset temperature, for example, the preset temperature can be set to 10°C. Since there is a heat transfer temperature difference between the temperature of the motor electronic control and the inlet and outlet water temperatures of the motor electronic control, the two temperatures are closely related. You can also add a motor electronic control temperature judgment to ensure that the temperature of the motor electronic control is at a low value, and the outlet water temperature of the motor electronic control is also low, thereby improving control stability.

[0103] When the heat dissipation Q that can be recovered by the motor electronic control is obtained motor_sp The heating capacity Q that can be achieved by running the motor electric control source heat pump heat_MSHP_sp The difference is within the preset range, that is, the heat dissipation Q motor_sp And heating capacity Q heat_MSHP_sp If the values ​​are similar, it means that the vehicle has been parked for a long time, is lightly loaded, or is driving downhill, etc. The power of the motor and electronic control is reduced, and its heat dissipation is also reduced, which can no longer meet the heating demand. It may even cause the temperature of the motor and electronic control to start to drop due to insufficient waste heat. The priority of the operating mode is used to determine whether the battery source heat pump operating mode is met. Therefore, the heat absorption of the battery source heat pump from the battery cell, the battery cell temperature, and the ambient temperature are used to determine whether the operating conditions of the battery source heat pump operating mode are met.

[0104] If the detected battery cell temperature is higher than the minimum temperature T for running the battery source heat pump Min_BattHP_run , and the ambient temperature is lower than the minimum ambient temperature for the operation of the air source heat pump. According to the calculated heating capacity and duration of the battery source heat pump, if the heating capacity and duration of the battery source heat pump also meet the heating requirements, and the heating capacity of the motor electronically controlled source heat pump at this time is lower than the heating capacity of the battery source heat pump corresponding to the battery core temperature at this time, the three-source heat pump unit can switch from the motor electronically controlled source heat pump operation mode to the battery source heat pump operation mode.

[0105] Based on the above embodiment, optionally, if the operating conditions of the battery source heat pump operating mode are not met, the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump, and the relationship between the heating capacity of the motor-controlled heat source pump and the heating capacity of the air source heat pump are determined;

[0106] If the ambient temperature is higher than the minimum ambient temperature for operating the air source heat pump, and the heating capacity of the motor-controlled heat source pump is lower than that of the air source heat pump, the three-source heat pump unit switches from the motor-controlled heat source pump operation mode to the air source heat pump operation mode.

[0107] Specifically, the current three-source heat pump unit is operating in the motor-controlled source heat pump mode. It is judged that it does not meet the battery source heat pump operation mode. According to the operation mode priority, it is judged whether it meets the air source heat pump operation mode. If the detected ambient temperature is greater than or equal to the minimum ambient temperature for operating the air source heat pump, the heating capacity Q that can be achieved by operating the air source heat pump is calculated. heat_ASHP_sp , if the heating capacity of the motor-controlled heat pump is Q heat_MSHP_sp Less than the heating capacity Q of the air source heat pump corresponding to the ambient air temperature at this time heat_ASHP_sp , the three-source heat pump unit switches from the motor-controlled source heat pump operation mode to the air-source heat pump operation mode.

[0108] Figure 4 A flow chart of another method for controlling the switching of the operation mode of the vehicle according to the priority of the operation parameters and the operation mode of the heat pump unit provided by the embodiment of the present invention is shown in FIG. Figure 4 Based on the above embodiment, the method steps include:

[0109] S410: The three-source heat pump unit operates in the battery source heat pump mode, and determines whether the initial operating conditions of the motor-controlled source heat pump mode are met based on the outlet water temperature of the motor-controlled source heat pump mode; if so, the three-source heat pump unit switches from the battery source heat pump mode to the motor-controlled source heat pump mode;

[0110] Specifically, the current three-source heat pump unit operates in the battery source heat pump operation mode. According to the operation mode priority, it is first determined whether it meets the motor-controlled source heat pump operation mode. First, the outlet water temperature of the motor-controlled source heat pump is determined to determine whether it meets the initial operation conditions of the motor-controlled source heat pump operation mode. For example, the outlet water temperature of the motor-controlled source heat pump is detected. If the outlet water temperature of the motor-controlled source heat pump is higher than the minimum temperature T that allows the motor-controlled source heat pump to operate, the motor-controlled source heat pump is automatically turned on. Min_MSHP_run In order to prevent frequent switching from the battery source heat pump operation mode to the motor control source mode, the minimum temperature T of the motor control source heat pump can be set as Min_MSHP_run Add the preset temperature as an entry judgment condition to detect whether the outlet water temperature of the motor control is greater than the minimum temperature T that allows the motor control source heat pump to operate. Min_MSHP_runA preset temperature, for example, can be set to 5°C as a hysteresis. Furthermore, a condition can be added to detect motor temperatures exceeding 65°C. The motor control temperature and the inlet and outlet water temperatures of the motor control have a heat transfer temperature difference, and the two temperatures are closely related. Adding the motor temperature as a criterion ensures that the motor control temperature remains high, and the outlet water temperature of the motor control is also high, improving control stability. Accordingly, the outlet water temperature of the motor control also increases within a certain period of time. For example, if the outlet water temperature of the motor control increases by at least 5°C within 2 minutes, this indicates that the vehicle is operating under load in most scenarios, with moderate or heavy loads, and the motor control is continuously heating. This indicates that the heat pump unit meets the entry-level operating conditions (i.e., initial operating conditions) for the motor control source heat pump mode, thereby switching the three-source heat pump unit from the battery source heat pump mode to the motor control source heat pump mode.

[0111] S420. If not satisfied, detect the relationship between the battery cell temperature and the minimum temperature of the battery source heat pump, and the relationship between the ambient temperature and the minimum ambient temperature of the air source heat pump operation mode; wherein, if the battery cell temperature is lower than the minimum temperature of the battery source heat pump, and the ambient temperature is greater than or equal to the minimum ambient temperature of the air source heat pump operation mode, the three-source heat pump unit switches from the battery source heat pump operation mode to the air source heat pump operation mode.

[0112] Specifically, if the operating conditions of the motor-controlled heat pump operation mode are not met, the air-source heat pump operation mode is determined according to the operation mode priority. If the battery core temperature is lower than the minimum temperature T Min_BattHP_run , and the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump, the three-source heat pump unit switches from the battery source heat pump operation mode to the air source heat pump operation mode.

[0113] Figure 5 A flow chart of another method for controlling the switching of the operation mode of the vehicle according to the priority of the operation parameters and the operation mode of the heat pump unit provided by the embodiment of the present invention is shown in FIG. Figure 5 Based on the above embodiment, the method steps include:

[0114] S510: The three-source heat pump unit operates in the air source heat pump operation mode. If the outlet water temperature of the motor electronic control is greater than the minimum temperature for operating the motor electronic control source heat pump, the heating capacity of the motor electronic control heat source pump is greater than the heating capacity of the air source heat pump, and the outlet water temperature of the motor electronic control is greater than the preset temperature for a preset time, the three-source heat pump unit switches from the air source heat pump operation mode to the motor electronic control source heat pump operation mode.

[0115] Specifically, the current three-source heat pump unit is operating in the air source heat pump operation mode. According to the operation mode priority, it is first determined whether it meets the motor-controlled source heat pump operation mode. First, the outlet water temperature of the motor-controlled source heat pump is determined to determine whether it meets the initial operation conditions of the motor-controlled source heat pump operation mode. For example, the outlet water temperature of the motor-controlled source heat pump is detected. If the outlet water temperature of the motor-controlled source heat pump is higher than the minimum temperature T that allows the motor-controlled source heat pump to operate, the motor-controlled source heat pump is automatically turned on. Min_MSHP_run In order to prevent frequent switching from the battery source heat pump operation mode to the motor control source mode, the minimum temperature T of the motor control source heat pump can be set as Min_MSHP_run Add the preset temperature as an entry judgment condition to detect whether the outlet water temperature of the motor control is greater than the minimum temperature T that allows the motor control source heat pump to operate. Min_MSHP_run Add a preset temperature, for example, 5°C as the hysteresis. Furthermore, you can add a condition to detect if the motor temperature is higher than 65°C. The motor control temperature and the inlet and outlet water temperatures of the motor control have a heat transfer temperature difference, and the two temperatures are closely related. Adding the motor temperature as a judgment ensures that the motor control temperature is at a high value, and the outlet water temperature of the motor control is also high, improving control stability.

[0116] When the heating capacity of the motor-controlled heat source pump is greater than that of the air-source heat pump, it can be ensured that once the motor-controlled heat source pump is in operation, the heating capacity of the motor-controlled heat source pump is greater than the corresponding heating capacity of the air-source heat pump at the current ambient temperature. This also indicates that the vehicle is in a long driving scenario, is heavily loaded, or is on an uphill road. The motor-controlled heat source pump has high power, its heat dissipation is also increased, and the heating capacity is large. Correspondingly, the outlet water temperature of the motor-controlled heat source is also increased within a certain period of time. For example, if the outlet water temperature of the motor-controlled heat source is set to increase by at least 5°C within 2 minutes, it can also be explained that most of the vehicle's operating scenarios are under load driving, and the load is moderate or large. The motor-controlled heat source pump is in a continuous state of heating, thereby switching the three-source heat pump unit from the air-source heat pump operation mode to the motor-controlled heat source operation mode.

[0117] S520: If the heating capacity of the motor-controlled heat source pump is less than the heating capacity of the air-source heat pump, and the outlet water temperature of the motor-controlled heat source pump is less than the preset temperature for a preset time, determine whether the operating conditions of the battery-source heat pump operating mode are met based on the amount of heat absorbed by the battery cell, the battery cell temperature, and the ambient temperature;

[0118] Among them, if the battery cell temperature is greater than the minimum temperature T of the battery source heat pump Min_BattHP_run, if the ambient temperature is lower than the minimum ambient temperature for the operation of the air source heat pump, the heating capacity of the battery source heat pump is determined according to the heat absorption of the battery cell by the battery source heat pump and the input power of the compressor; if the heating capacity of the battery source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery source heat pump operation mode are met, and the three-source heat pump unit switches from the air source heat pump operation mode to the battery source heat pump operation mode.

[0119] Specifically, if it is determined that the operating conditions of the motor-controlled heat pump operating mode are not met, it is determined whether the battery cell temperature is higher than the minimum temperature T for operating the battery-controlled heat pump. Min_BattHP_run , and whether the ambient temperature is lower than the minimum ambient temperature for running the air source heat pump. Min_BattHP_run It is the entry condition for running the battery source heat pump. When the battery cell temperature is higher than the minimum temperature T Min_BattHP_run , and the ambient temperature is lower than the minimum ambient temperature for operating the air source heat pump. At the same time, the heating capacity of the battery source heat pump is greater than the heating standard. For example, within the cycle when the battery core temperature drops from 18°C ​​to 12°C, 5kW of heating capacity can be obtained, and the operating time can be more than 60 minutes. It can be determined that the heating requirements are met by operating according to the 15-minute demand. Therefore, the three-source heat pump unit switches from the air source heat pump operation mode to the battery source heat pump operation mode.

[0120] Optionally, the operating mode also includes a natural heating operating mode. When the outlet water temperature of the motor electronic control is greater than the first preset temperature and there is a heating demand, the operating mode of the three-source heat pump unit is switched to the natural heating operating mode; when the outlet water temperature of the motor electronic control is lower than the second preset temperature, the operating mode of the three-source heat pump unit is switched to the motor electronic control source heat pump operating mode, and the first preset temperature is higher than the second preset temperature.

[0121] Specifically, the natural heating mode operates when the outlet water temperature of the motor control is within the typical hot water supply temperature range. For example, if the outlet water temperature of the motor control is between 40°C and 55°C, there is no need for the compressor heat pump system to operate. Instead, the motor control water circuit, the battery water circuit, and the cockpit water circuit are connected in series, transferring the heat of the motor control at the appropriate temperature to the battery and cockpit. Therefore, when the outlet water temperature of the motor control is greater than or equal to a first preset temperature, typically set at 46°C, if there is a heating demand, the system can switch to the natural heating mode. This mode continues until the outlet water temperature of the motor control falls below a second preset temperature, typically set at 38°C, at which point the system switches from the natural heating mode to the motor control source heat pump mode.

[0122] Figure 6 A schematic diagram of a control flow of a heat pump unit in standby mode provided by an embodiment of the present invention, see Figure 6 The method process includes:

[0123] The three-source heat pump unit is in standby mode. S601: Detect the outlet water temperature of the motor and electronic control. If the outlet water temperature of the motor and electronic control is greater than or equal to the minimum temperature T that allows the motor and electronic control source heat pump to operate, Min_MSHP_run , then S602, determine whether the outlet water temperature of the motor electronic control is increased within a certain period of time. For example, if the outlet water temperature of the motor electronic control is increased by at least 5°C within 2 minutes, it can be explained that most of the vehicle's operating scenarios are under load driving, and the load is moderate or large, and the motor electronic control is in continuous heating. If so, then S603, obtain the heating capacity Q of the air source heat pump heat_ASHP_sp ; S604, obtain the heating capacity Q of the motor-controlled heat source pump heat_MSHP_sp ; S605, compare the heating capacity Q of the motor-controlled heat source pump heat_MSHP_sp And the heating capacity of air source heat pump Q heat_ASHP_sp , if the heating capacity of the motor-controlled heat source pump is Q heat_MSHP_sp Greater than the heating capacity of the air source heat pump Q heat_ASHP_sp , it can be ensured that once the electric motor-controlled heat pump is in operation, the heating capacity of the electric motor-controlled heat pump will be greater than the corresponding heating capacity of the air source heat pump at the current ambient temperature, and it will be more efficient and last longer. S606: Switch the three-source heat pump unit from standby mode to electric motor-controlled heat pump operation mode.

[0124] If the answer in one of S601, S602 or S605 is no, then S607 is to determine whether the battery cell temperature is higher than the minimum temperature T for operating the battery source heat pump. Min_BattHP_run For example, in order to prevent frequent switching of the battery source heat pump operation mode, the minimum temperature T of the battery source heat pump can be set to Min_BattHP_run Add the preset temperature as the judgment temperature. For example, the preset temperature can be set to 6°C as the hysteresis. If yes, then S608: determine whether the ambient temperature is less than the minimum ambient temperature T for running the air source heat pump. Air_ASHP_run The minimum ambient temperature of the air source heat pump is T Air_ASHP_run The typical setting value is -15℃. For example, according to the application, the detection environment temperature can be set to detect whether it is lower than the minimum environment temperature T of the air source heat pump. Air_ASHP_run +22℃ is used as the judgment threshold. If yes, then S609, calculate the heating capacity Q of the battery source heat pump. heat_BattHP_sp and duration Δt; S610, determine whether the heating capacity of the battery source heat pump is greater than the heating standard, for example, the heating capacity of the battery source heat pump Q heat_BattHP_sp If the power is greater than or equal to 5KW and the duration Δt is greater than or equal to 15 minutes, then S611: the three-source heat pump unit switches from the standby mode to the battery source heat pump operation mode.

[0125] If one of S607, S608 or S610 is judged as no, then S612 indicates that the operating conditions of the battery source heat pump operation mode are not met, and it is determined whether the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump. If so, S613, the three-source heat pump unit switches from standby mode to air source heat pump operation mode, directly absorbing heat from the environment for heating. If not, S614, determines whether the battery core temperature is less than the minimum temperature T for operating the battery source heat pump. Min_BattHP_run , and whether the ambient temperature is lower than the minimum ambient temperature for running the air source heat pump, in order to prevent the frequent switching of the battery source heat pump operation mode, the minimum temperature T Min_BattHP_run The preset temperature is added as the judgment temperature. For example, the preset temperature can be set to 6°C as the hysteresis. If so, S615, the three-source heat pump unit switches to air heating mode. The air heating mode is the air heating resistance heating mode, which directly heats the room with resistance.

[0126] Figure 7 A schematic diagram of the control flow of a heat pump unit provided by an embodiment of the present invention when it is in the motor-controlled source heat pump operation mode, see Figure 7 The method process includes:

[0127] The current three-source heat pump unit is operating in the motor-controlled source heat pump mode. S701: Determine whether the outlet water temperature of the motor-controlled source heat pump is lower than the minimum temperature T for operating the motor-controlled source heat pump. Min_MSHP_run For example, in order to prevent the frequent switching of the motor-controlled heat pump operation mode, the minimum temperature T of the battery-controlled heat pump can be set to Min_BattHP_run Subtract the preset temperature as the entry judgment condition for mode switching, and detect whether the outlet water temperature of the motor electronic control is lower than the minimum temperature T for running the battery source heat pump. Min_BattHP_run Subtract the preset temperature, for example, the preset temperature can be set to 10°C. If S702, check whether the battery cell temperature is greater than or equal to the minimum temperature T for running the battery source heat pump Min_BattHP_run For example, in order to prevent frequent switching of the battery source heat pump operation mode, the minimum temperature T of the battery source heat pump can be set to Min_BattHP_run Add the preset temperature as the judgment temperature. For example, the preset temperature can be set to 6°C as the hysteresis. If S703, determine whether the ambient temperature is less than the minimum ambient temperature T for running the air source heat pump. Air_ASHP_run , the minimum ambient temperature T of the air source heat pump Air_ASHP_run The typical setting value is -15℃. For example, according to the application, the detection environment temperature can be set to detect whether it is lower than the minimum environment temperature T of the air source heat pump. Air_ASHP_run +22℃ is used as the judgment threshold. If S704, calculate the heating capacity Q of the battery source heat pump heat_BattHP_spand duration Δt; S705, determining whether the heating capacity of the battery source heat pump is greater than the heating standard, if so, S706, the three-source heat pump unit switches from the motor-controlled source heat pump operation mode to the battery source heat pump operation mode.

[0128] If one of S702, S703 or S705 is judged as no, then S707, judge whether the ambient temperature is greater than or equal to the minimum ambient temperature T for running the air source heat pump. Air_ASHP_run If yes, then S708, calculate the heating capacity Q of the air source heat pump heat_ASHP_sp , S709, calculate the heating capacity Q of the motor-controlled heat source pump heat_MSHP_sp , S710, compare the heating capacity Q of the motor-controlled heat source pump heat_MSHP_sp And the heating capacity of air source heat pump Q heat_ASHP_sp , if the heating capacity of the motor-controlled heat source pump is Q heat_MSHP_sp Less than the heating capacity of the air source heat pump Q heat_ASHP_sp , S711, switch the three-source heat pump unit from the motor-controlled source heat pump operation mode to the air source heat pump operation mode.

[0129] If the answer in S707 or S710 is no, then S712 determines whether the battery cell temperature is lower than the minimum temperature T for operating the battery source heat pump. Min_BattHP_run , and whether the ambient temperature is lower than the minimum ambient temperature T for running the air source heat pump Air_ASHP_run In order to prevent the frequent switching of the battery source heat pump operation mode, the lowest temperature T Min_BattHP_run The preset temperature is added as the judgment temperature. For example, the preset temperature can be set to 6°C as the hysteresis. If so, S713, the three-source heat pump unit switches to air heating mode. The air heating mode is the air heating resistance heating mode, which directly heats the room with resistance.

[0130] Figure 8 A schematic diagram of the control flow of a heat pump unit in a battery source heat pump operation mode provided by an embodiment of the present invention, see Figure 8 The method process includes:

[0131] The three-source heat pump unit operates in the battery source heat pump mode. S801: Detect the outlet water temperature of the motor control. If the outlet water temperature of the motor control is greater than or equal to the minimum temperature T that allows the motor control source heat pump to operate, Min_MSHP_run In order to prevent frequent switching from the battery source heat pump operation mode to the motor control source mode, the minimum temperature T of the motor control source heat pump can be set as Min_MSHP_run Add the preset temperature as an entry judgment condition to detect whether the outlet water temperature of the motor control is greater than the minimum temperature T that allows the motor control source heat pump to operate. Min_MSHP_runAdd the preset temperature, for example, the preset temperature can be set to 5°C as the hysteresis. Then S802, you can also add the condition of detecting that the motor temperature is higher than 65°C. The temperature of the motor electronic control and the inlet and outlet water temperatures of the motor electronic control have a heat transfer temperature difference, and the two temperatures are closely related. Adding the motor temperature as a judgment can ensure that the temperature of the motor electronic control is at a higher value, and the outlet water temperature of the motor electronic control is also high, thereby improving control stability. S803, determine whether the outlet water temperature of the motor electronic control is continuously greater than or equal to a certain temperature within a certain period of time, for example, the outlet water temperature of the motor electronic control is continuously greater than or equal to 35°C. If so, S804, switch the three-source heat pump unit from the battery source heat pump operation mode to the motor control source heat pump operation mode.

[0132] If one of S801, S802 or S803 is judged as no, then S805, judge whether the battery core temperature is lower than the minimum temperature T for operating the battery source heat pump. Min_BattHP_run , and whether the ambient temperature is lower than the minimum ambient temperature T for running the air source heat pump Air_ASHP_run If yes, then S806, the three-source heat pump unit switches from the battery source heat pump mode to the air source heat pump mode. If no, S807, the unit switches to the air heating mode to heat the cockpit.

[0133] Figure 9 A schematic diagram of the control flow of a heat pump unit in an air source heat pump operation mode provided by an embodiment of the present invention, see Figure 9 The method process includes:

[0134] The current three-source heat pump unit is running in air source heat pump mode. S901: Detect the outlet water temperature of the motor control. If the outlet water temperature of the motor control is higher than the minimum temperature T that allows the motor control heat pump to operate, Min_MSHP_run In order to prevent frequent switching from the battery source heat pump operation mode to the motor control source mode, the minimum temperature T of the motor control source heat pump can be set as Min_MSHP_run Add the preset temperature as an entry judgment condition to detect whether the outlet water temperature of the motor control is greater than the minimum temperature T that allows the motor control source heat pump to operate. Min_MSHP_run Add the preset temperature, for example, the preset temperature can be set to 5°C as the hysteresis.

[0135] Then judge S902, check whether the motor temperature is higher than 65℃. There is a heat transfer temperature difference between the temperature of the motor electronic control and the inlet and outlet water temperatures of the motor electronic control. The two temperatures are closely related. Adding the motor temperature as a judgment can ensure that the temperature of the motor electronic control is at a higher value, and the outlet water temperature of the motor electronic control is also high, thereby improving control stability. If so, then S903, obtain the heating capacity Q of the air source heat pump heat_ASHP_sp S904. Obtain the heating capacity Q of the motor-controlled heat source pump heat_MSHP_sp; S905, compare the heating capacity Q of the motor-controlled heat source pump heat_MSHP_sp And the heating capacity of air source heat pump Q heat_ASHP_sp , if the heating capacity of the motor-controlled heat source pump is Q heat_MSHP_sp Greater than the heating capacity of the air source heat pump Q heat_ASHP_sp S906: Determine whether the outlet water temperature of the motor electronic control is continuously greater than or equal to a certain temperature within a certain period of time. For example, if the outlet water temperature of the motor electronic control is continuously greater than or equal to 35°C, if so, S907: switch the three-source heat pump unit from the air source heat pump operation mode to the motor electronic control source heat pump operation mode.

[0136] If the answer in S905 or S906 is no, then S908 is to determine whether the battery cell temperature is greater than or equal to the minimum temperature T for operating the battery source heat pump. Min_BattHP_run In order to prevent the frequent switching of the battery source heat pump operation mode, the lowest temperature T Min_BattHP_run Add the preset temperature as the judgment temperature. For example, the preset temperature can be set to 6°C as the hysteresis. If yes, then S909: determine whether the ambient temperature is less than the minimum ambient temperature T for running the air source heat pump. Air_ASHP_run , the minimum ambient temperature T of the air source heat pump Air_ASHP_run The typical setting value is -15℃. For example, according to the application, the detection environment temperature can be set to detect whether it is lower than the minimum environment temperature T of the air source heat pump. Air_ASHP_run +22℃ is used as the judgment threshold. If S910, calculate the heating capacity Q of the battery source heat pump heat_BattHP_sp and duration Δt; S911, determining whether the heating capacity of the battery source heat pump is greater than the heating standard, if so, S912, switching the three-source heat pump unit from the air source heat pump operation mode to the battery source heat pump operation mode.

[0137] If the answer in S908, S909 or S911 is no, then S913 determines whether the battery cell temperature is lower than the minimum temperature T for operating the battery source heat pump. Min_BattHP_run , and whether the ambient temperature is lower than the minimum ambient temperature T for running the air source heat pump Air_ASHP_run In order to prevent the frequent switching of the battery source heat pump operation mode, the lowest temperature T Min_BattHP_run The preset temperature is added as the judgment temperature. For example, the preset temperature can be set to 6°C as the hysteresis. If so, S914, the three-source heat pump unit switches to air heating mode. The air heating mode is the air heating resistance heating mode, which directly heats the room with resistance.

[0138] Figure 10 A schematic diagram of the system structure of a three-source heat pump unit for a vehicle thermal management system according to an embodiment of the present invention is provided. Figure 10, including a refrigeration component, an air source heat pump 2, a motor-controlled heat source pump 3, a battery source heat pump 4 and a heat dissipation water tank 9. The refrigeration component includes a compressor 11, two condensers and two evaporators. The compressor 11 can be connected to one of the two condensers and at least one of the two evaporators. The two condensers are an air-cooled condenser 12 and a water condenser 17 respectively. The two evaporators are a cabin evaporator 13 and a water evaporator 14 respectively. The air source heat pump 2 is used to heat or cool the cabin and its inlet can be connected to the heat exchange outlet of the cabin evaporator 13. The outlet of the air source heat pump 2 can be connected to the water evaporator 14 and one of the heat exchange inlets of the cabin evaporator 13. When the air source heat pump 2 is working, that is, the air source heat pump operation mode, the compressor is used to absorb heat from the external ambient air to provide high-temperature hot water supply to the cockpit.

[0139] The motor-controlled heat source pump 3 is used to heat or cool the electric drive and its inlet can be connected to at least one of the heat exchange outlet of the air source heat pump 2, the heat exchange outlet of the water evaporator 14, and the heat exchange outlet of the water condenser 17. The outlet of the motor-controlled heat source pump 3 can be connected to at least one of the heat exchange inlet of the water condenser 17 and the inlet of the air source heat pump 2. When the motor-controlled heat source pump 3 is working, that is, the motor-controlled heat source pump operation mode, the compressor is used to absorb excess heat from the rotating and power-consuming motor control to provide high-temperature hot water supply to the cockpit.

[0140] The battery-source heat pump 4 is used to heat or cool the battery, and its inlet is connected to the heat exchange outlet of the water evaporator 14. The outlet of the battery-source heat pump 4 can be connected to either the inlet of the electric motor-controlled heat source pump 3 or the heat exchange inlet of the water evaporator 14. The inlet of the heat dissipation water tank 9 can be connected to the outlet of the electric motor-controlled heat source pump 3, and the outlet of the heat dissipation water tank 9 can be connected to either the inlet of the electric motor-controlled heat source pump 3 or the heat exchange inlet of the water evaporator 14. When the battery-source heat pump 4 is operating, that is, in the battery-source heat pump operation mode, the compressor is operated to absorb heat from the battery cells to provide high-temperature hot water supply to the cockpit.

[0141] The vehicle thermal management system of the electric vehicle provided in this embodiment can not only use the heat generated by the battery and the motor electronic control to heat the cabin, but also cool the battery and the electric drive through the heat dissipation water tank 9, and can also realize the cooling and heating of the battery, the cabin and the electric drive by the refrigeration component. Among them, the circulating fluid can directly heat or cool the motor electronic control heat source pump 3 after absorbing or releasing heat in the water evaporator 14 to heat or cool the motor electronic control. After absorbing or releasing heat in the water evaporator 14, the circulating fluid can also heat or cool the motor electronic control heat source pump 3 and the battery source heat pump 4 to heat or cool the motor electronic control and the battery at the same time, thereby improving the operating efficiency of the whole vehicle, increasing the reliability of the system operation, and increasing the cruising range of the electric vehicle, so that the electric vehicle can operate safely.

[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A thermal management control method for a three-source heat pump unit in a vehicle thermal management system, characterized in that: include: Obtain the operating parameters of the vehicle's three-source heat pump unit; According to the operating parameters and the judgment priority of the operating mode of the heat pump unit, the operating mode of the whole vehicle is controlled and switched; wherein the operating modes include a motor-controlled source heat pump operating mode, a battery-controlled source heat pump operating mode, and an air-source heat pump operating mode; the motor-controlled source heat pump operating mode is an operating mode in which excess heat is absorbed from the rotating and power-consuming motor control by operating the compressor; the battery-controlled source heat pump operating mode is an operating mode in which heat is absorbed from the battery cell by operating the compressor; and the air-source heat pump operating mode is an operating mode in which heat is absorbed from the external ambient air by operating the compressor; The judgment priority is as follows: if it is determined that the operation mode of the motor-controlled heat pump is met, then the operation mode of the whole vehicle is controlled to be switched to the motor-controlled heat pump operation mode; if it is determined that the operation mode of the motor-controlled heat pump is not met, then whether the operation mode of the battery-controlled heat pump is met is determined; if it is determined that the operation mode of the battery-controlled heat pump is met, then the operation mode of the whole vehicle is controlled to be switched to the battery-controlled heat pump operation mode; If it is determined that the vehicle does not conform to the motor-controlled heat pump operation mode and does not conform to the battery-source heat pump operation mode, then it is determined whether the vehicle conforms to the air-source heat pump operation mode. If it is determined that the vehicle conforms to the air-source heat pump operation mode, then the operation mode of the vehicle is switched to the air-source heat pump operation mode. The operating parameters include the outlet water temperature of the motor electronic control, the heat dissipation of the motor electronic control, the input power of the compressor, the ambient temperature and the speed of the compressor; When the three-source heat pump unit is in standby mode, judging whether the initial operating conditions of the motor-controlled source heat pump operation mode are met according to the outlet water temperature of the motor-controlled source heat pump; If the initial operating conditions of the motor-controlled heat pump operation mode are met, the heating capacity of the motor-controlled heat pump is determined according to the heat dissipation of the motor-controlled heat pump and the input power of the compressor; the heating capacity of the air-source heat pump is determined according to the outlet water temperature of the motor-controlled heat pump, the ambient temperature and the speed of the compressor; The heating capacity of the motor-controlled source heat pump is compared with the heating capacity of the air-source heat pump. If the heating capacity of the motor-controlled source heat pump is greater than that of the air-source heat pump, the three-source heat pump unit is switched from the standby mode to the motor-controlled source heat pump operation mode.

2. The thermal management control method of a three-source heat pump unit in a vehicle thermal management system according to claim 1, characterized in that: The operating parameters also include the heating capacity of the battery source heat pump and the battery cell temperature; If the initial operating conditions of the motor-controlled heat pump operating mode are not met, determining whether the operating conditions of the battery-source heat pump operating mode are met based on the amount of heat absorbed by the battery-source heat pump from the battery cell, the battery cell temperature, and the ambient temperature; Among them, if the battery cell temperature is greater than the minimum temperature for operating the battery-source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air-source heat pump, the heating capacity of the battery-source heat pump is determined according to the heat absorption of the battery-source heat pump from the battery cell and the input power of the compressor; if the heating capacity of the battery-source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery-source heat pump operation mode are met, and the three-source heat pump unit is switched from the standby mode to the battery-source heat pump operation mode.

3. The thermal management control method of a three-source heat pump unit in a vehicle thermal management system according to claim 2, characterized in that: If the operating conditions of the battery source heat pump operation mode are not met, the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump is judged. If the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump, the three-source heat pump unit is switched from the standby mode to the air source heat pump operation mode.

4. The thermal management control method of a three-source heat pump unit in a vehicle thermal management system according to claim 1, characterized in that: The operating parameters also include the heating capacity of the battery source heat pump and the battery cell temperature; The three-source heat pump unit operates in the motor-controlled heat pump operation mode, and the difference between the heat dissipation of the motor-controlled heat pump and the heating capacity of the motor-controlled heat pump is within a preset range. Then, it is determined whether the operating conditions of the battery-source heat pump operation mode are met based on the amount of heat absorbed by the battery-source heat pump from the battery cell, the battery cell temperature, and the ambient temperature. Among them, if the battery cell temperature is greater than the minimum temperature for operating the battery-source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air-source heat pump, the heating capacity of the battery-source heat pump is determined according to the heat absorption of the battery-source heat pump from the battery cell and the input power of the compressor; if the heating capacity of the battery-source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery-source heat pump operation mode are met, and the three-source heat pump unit is switched from the motor-controlled source heat pump operation mode to the battery-source heat pump operation mode.

5. The thermal management control method of a three-source heat pump unit in a vehicle thermal management system according to claim 4, characterized in that: If the operating conditions of the battery source heat pump operating mode are not met, determining the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump, and the relationship between the heating capacity of the motor-controlled heat source pump and the heating capacity of the air source heat pump; If the ambient temperature is greater than the minimum ambient temperature for operating the air source heat pump, and the heating capacity of the motor-controlled source heat pump is less than the heating capacity of the air source heat pump, the three-source heat pump unit switches from the motor-controlled source heat pump operation mode to the air source heat pump operation mode.

6. The thermal management control method of a three-source heat pump unit in a vehicle thermal management system according to claim 2, characterized in that: The three-source heat pump unit operates in the battery source heat pump operation mode, and determines whether the initial operation conditions of the motor-controlled source heat pump operation mode are met according to the outlet water temperature of the motor-controlled source heat pump; If the conditions are met, the three-source heat pump unit switches from the battery source heat pump operation mode to the motor-controlled source heat pump operation mode; If not satisfied, the relationship between the battery cell temperature and the minimum temperature for operating the battery source heat pump, as well as the relationship between the ambient temperature and the minimum ambient temperature for operating the air source heat pump operation mode, are detected; wherein, if the battery cell temperature is lower than the minimum temperature for operating the battery source heat pump, and the ambient temperature is greater than or equal to the minimum ambient temperature for operating the air source heat pump operation mode, the three-source heat pump unit switches from the battery source heat pump operation mode to the air source heat pump operation mode.

7. The thermal management control method of a three-source heat pump unit in a vehicle thermal management system according to claim 3, characterized in that: The three-source heat pump unit operates in the air source heat pump operation mode. If the outlet water temperature of the motor electronic control is greater than the minimum temperature for operating the motor electronic control source heat pump, the heating capacity of the motor electronic control source heat pump is greater than the heating capacity of the air source heat pump, and the outlet water temperature of the motor electronic control is greater than the preset temperature for a preset time, the three-source heat pump unit switches from the air source heat pump operation mode to the motor electronic control source heat pump operation mode. If the heating capacity of the motor-controlled heat pump is less than the heating capacity of the air-source heat pump, and the outlet water temperature of the motor-controlled heat pump is less than a preset temperature for a preset time, then judging whether the operating conditions of the battery-source heat pump operating mode are met based on the amount of heat absorbed by the battery-source heat pump from the battery cell, the battery cell temperature, and the ambient temperature; Among them, if the battery cell temperature is greater than the minimum temperature for operating the battery-source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air-source heat pump, the heating capacity of the battery-source heat pump is determined according to the heat absorption of the battery-source heat pump from the battery cell and the input power of the compressor; if the heating capacity of the battery-source heat pump is greater than the heating standard, it is judged that the operating conditions of the battery-source heat pump operation mode are met, and the three-source heat pump unit is switched from the air-source heat pump operation mode to the battery-source heat pump operation mode.

8. The thermal management control method for a three-source heat pump unit in a vehicle thermal management system according to claim 3, 6 or 7, characterized in that: The operation mode also includes an air-heating operation mode, and the air-heating operation mode is an air-heating resistance heating mode; If the battery core temperature is lower than the minimum temperature for operating the battery source heat pump, and the ambient temperature is lower than the minimum ambient temperature for operating the air source heat pump, the operation mode of the three-source heat pump unit is switched to the air heating operation mode.

9. The thermal management control method for a three-source heat pump unit in a vehicle thermal management system according to any one of claims 1 to 7, characterized in that: The operation mode also includes a natural heating operation mode. When the outlet water temperature of the motor electronic control is greater than a first preset temperature and there is a heating demand, the operation mode of the three-source heat pump unit is switched to the natural heating operation mode. When the outlet water temperature of the motor electronic control is lower than the second preset temperature, the operation mode of the three-source heat pump unit is switched to the motor electronic control source heat pump operation mode, and the first preset temperature is higher than the second preset temperature.

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