System and method for testing integrated thermal management performance of electric vehicle

Abstract

The invention discloses an integrated thermal management performance test system and test method of an electric automobile, and relates to the technical field of thermal management test of the electric automobile, and the technical scheme is characterized in that the integrated thermal management performance test system comprises a test system loop and a constant temperature and humidity chamber; the test system loop is installed in a constant temperature and humidity chamber, and the constant temperature and humidity chamber is used for simulating different environment working conditions; the test system loop is provided with an HVAC, a battery pack, a motor and controller, a compressor, a chiller refrigeration device, an evaporator, a condenser, a radiator, a pipeline, a plurality of valves and a plurality of water pumps. The performance testing system further comprises a plurality of fans, a plurality of thermometers, a plurality of flowmeters and a plurality of pressure sensors. According to the invention, air conditioning system performance testing is taken as a core, battery cooling, motor cooling and waste heat recovery performance testing is considered, independent operation performance of the thermal management system can be tested, integrated functions of the thermal management system can also be tested, and the testing system has the characteristics of being simple, high in testing efficiency and high in matching performance.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicle thermal management testing, and more specifically, to an integrated thermal management performance testing system and a testing method for an electric vehicle. Background Art

[0002] The performance of the thermal management system of electric vehicles has a very important impact on improving the driving safety and driving range of electric vehicles and improving the comfort of the cab. As the thermal management system of electric vehicles develops towards integration, the integrated thermal management system of electric vehicles currently includes air conditioning system, battery cooling system, motor cooling and waste heat recovery system. The automotive thermal management system consists of multiple components. In order to ensure the safety of electric vehicles and improve the efficiency of the thermal management system, it is necessary to test the performance of the automotive thermal management system.

[0003] At present, the thermal management systems of new energy vehicles are all modified on actual vehicles, and the performance test of the thermal management system is also carried out after the actual vehicle is modified. Since the integrated thermal management system of electric vehicles involves many key components, the modification of the actual vehicle is limited by space, which poses certain challenges to the pipeline layout of the thermal management system and the installation of test components (temperature, pressure, flow, etc.), which greatly affects the test efficiency of the thermal management system. At the same time, for the performance test of the thermal management system, it is usually necessary to conduct a comprehensive evaluation of the air-conditioning performance, battery heat dissipation performance, motor and controller heat dissipation performance, and motor waste heat recovery performance. If a separate test method is used, the test efficiency is low, and the integrated function of the thermal management system cannot be tested.

[0004] Therefore, the present invention aims to provide an integrated thermal management performance testing system and testing method for electric vehicles to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide an integrated thermal management performance test system and test method for electric vehicles. The present invention develops a test system and test method that takes testing the performance of an air-conditioning system as the core and takes into account testing battery cooling, motor cooling and waste heat recovery performance. The system and test method can test the performance of the thermal management system running independently and can also test the integrated functions of the thermal management system. The system has the characteristics of a simple test system, high test efficiency and high matching.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions: an integrated thermal management performance test system for electric vehicles, comprising a test system loop and a constant temperature and humidity chamber; the test system loop is installed in the constant temperature and humidity chamber, and the constant temperature and humidity chamber is used to simulate different environmental conditions;

[0007] The test system loop is provided with HVAC, battery pack, motor and controller, compressor, chiller refrigeration device, evaporator, condenser, radiator, pipeline, multiple valves and multiple water pumps. The pipeline is used to connect the test system loop, multiple valves are installed on the pipeline to control the connection and disconnection of the pipeline, and multiple water pumps are installed in the pipeline to adjust the flow of coolant;

[0008] The performance testing system also includes multiple fans, multiple thermometers, multiple flow meters and multiple pressure sensors; multiple fans are used to adjust the air flow inside the system, multiple thermometers are used to measure the air temperature flowing through the system and the refrigerant temperature flowing through the pipeline, multiple flow meters are used to measure the air flow flowing through the system or the refrigerant flow flowing through the pipeline, and multiple pressure sensors are used to measure the coolant pressure flowing through the pipeline.

[0009] The present invention is further configured as follows: the multiple valves respectively include an electronic expansion valve, a three-way valve and a four-way valve, and the switching of different valves is used to implement performance testing of different thermal management performance testing subsystems, and performance testing of thermal management performance testing subsystems that operate independently and in an integrated manner can be performed.

[0010] The present invention is further configured as follows: the thermal management performance test subsystems respectively include an HVAC independent cooling performance test subsystem, a battery pack independent cooling performance test subsystem, an HVAC and battery pack simultaneous cooling performance test subsystem, an HVAC, battery pack and motor simultaneous cooling performance test subsystem, an HVAC heating performance test subsystem, and a motor waste heat recovery performance test subsystem.

[0011] The present invention is further configured as follows: the constant temperature and humidity chamber specifically includes a constant temperature and humidity chamber 1 and a constant temperature and humidity chamber 2, the HVAC is installed in the constant temperature and humidity chamber 1, the battery pack, the motor and the controller, the condenser and the radiator are installed in the constant temperature and humidity chamber 2, and the HVAC is connected to the battery pack, the motor and the controller, the condenser and the radiator through pipelines to form a test system loop.

[0012] The present invention also provides a method for testing the integrated thermal management performance of an electric vehicle, comprising the following steps:

[0013] S1. Control the temperature and humidity of the internal environment of the performance test system through a constant temperature and humidity chamber;

[0014] S2. Using a fan to adjust the air flow inside the performance test system;

[0015] S3. Use a thermometer to measure the air temperature flowing through the system and the refrigerant temperature flowing through the pipeline, a flow meter to measure the air flow rate flowing through the system or the refrigerant flow rate flowing through the pipeline, and a pressure sensor to measure the coolant pressure flowing through the pipeline to obtain specific values ​​of the performance test system.

[0016] S4. Obtain the performance data of the performance test system through specific numerical calculations, thereby completing the integrated thermal management performance test.

[0017] In summary, the present invention has the following beneficial effects:

[0018] 1. The present invention develops a test system and a test method that focuses on testing the performance of the air conditioning system and takes into account the testing of battery cooling, motor cooling and waste heat recovery performance. It can test the performance of the independent operation of the thermal management system and can also test the integrated function of the thermal management system. It has the characteristics of simple test system, high test efficiency and high matching.

[0019] 2. The present invention specifically constructs a test system for the performance of a thermal management system based on an existing integrated thermal management system, and integrates the test methods of battery heat dissipation, motor and its controller heat dissipation, and motor waste heat recovery performance based on the performance test of the air-conditioning system. The HVAC is placed in a constant temperature and humidity chamber 1, and the condenser, radiator, battery pack, motor and controller are placed in a constant temperature and humidity chamber 2. The temperature of the constant temperature and humidity chamber is controlled to simulate different environmental conditions. The test system connects the test system loop through pipelines and valves, and a water pump and a fan are used to adjust the coolant and air flow. The performance tests of different subsystems and the test of the integrated function of the thermal management system are achieved by switching the electronic expansion valve, the three-way valve, and the four-way valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of an integrated thermal management performance testing system for an electric vehicle in Example 1 of the present invention;

[0021] Figure 2 This is an assembly diagram of the internal test bench of the constant temperature and humidity chamber 1 in Example 1 of the present invention;

[0022] Figure 3 This is an assembly diagram of the test bench inside the constant temperature and humidity chamber 2 in Example 1 of the present invention;

[0023] Figure 4 This is a working mode diagram of an integrated thermal management performance test system for an electric vehicle in Example 1 of the present invention;

[0024] Figure 5 This is a schematic diagram of an integrated thermal management performance test of an electric vehicle in Example 2 of the present invention. DETAILED DESCRIPTION

[0025] The following is combined with Figure 1-5 The present invention is described in further detail.

[0026] Embodiment 1: An integrated thermal management performance testing system for electric vehicles, such as Figure 1 As shown, based on the performance test of the air-conditioning system, the test system integrates the heat dissipation of the battery, the heat dissipation of the motor and its controller, and the waste heat recovery performance of the motor; specifically, the HVAC is placed in a constant temperature and humidity chamber 1, and the condenser, radiator, battery pack, motor and controller are placed in a constant temperature and humidity chamber 2, and different environmental conditions are simulated by controlling the temperature of the constant temperature and humidity chamber; the test system connects the test system loop through pipes and valves, and the water pump and fan are used to adjust the coolant and air flow. The performance tests of different subsystems and the test of the integrated function of the thermal management system are realized by switching the electronic expansion valve, three-way valve and four-way valve.

[0027] In this embodiment, the temperature and humidity of the HVAC external environment are specifically controlled by a constant temperature and humidity chamber 1; the temperature and humidity of the external environment of the battery pack, motor and controller are controlled by a constant temperature and humidity chamber 2; the air volume of the HVAC is controlled by a fan 1, and the HVAC air flow is measured by a flow meter 1; the temperature of the air flowing through the HVAC is measured by dry-bulb thermometers 1 and 2, and the cooling / heating performance of the HVAC is calculated; the air volume of the radiator and the condenser is controlled by a fan 2, the air temperature of the front-end heat dissipation module is measured by a temperature sensor 9, and the air flow of the front-end heat dissipation module is measured by a flow meter 5; the refrigerant pressure flowing through the condenser is measured by pressure sensors 1 and 2, the refrigerant temperature flowing through the condenser is measured by temperature sensors 3 and 4, and the refrigerant flow is measured by a flow meter 2; Force sensors 5 and 6 measure the coolant pressure flowing through the battery pack, temperature sensors 4 and 5 measure the coolant temperature flowing through the battery pack, and flow meter 3 measures the coolant flow rate in the battery pack circuit; pressure sensors 6 and 7 measure the coolant pressure flowing through the motor, temperature sensors 6 and 7 measure the coolant temperature flowing through the motor, and flow meter 4 measures the coolant flow rate in the motor circuit; solenoid valves and electronic expansion valves are used to control the flow of refrigerant in the HVAC circuit and chiller circuit to test the independent cooling performance of the air-conditioning system, the independent cooling performance of the battery, and the joint cooling performance of the air-conditioning and battery; the performance of the motor cooling mode and the motor waste heat recovery mode is tested by switching the four-way valve and the three-way valve; according to the test requirements, the PTC heater can be turned on to test the heating performance.

[0028] The test bench of the integrated thermal management performance test system of the electric vehicle in this embodiment is assembled as follows: Figure 2 and Figure 3 As shown, the test bench specifically includes the types, quantities and performance requirements of test-related components as shown in Table 1:

[0029] Table 1 Type, quantity and performance requirements of components in the test bench

[0030]

[0031] At the same time, considering that there are test requirements for air conditioning cooling / heating performance, battery pack cooling / heating performance, and motor cooling performance, the test system has different working modes under different test requirements, such as: HVAC independent cooling / heating performance test, battery independent cooling performance test, HVAC and battery simultaneous cooling performance test, HVAC, battery pack, motor simultaneous cooling performance test, motor waste heat recovery performance test, each test condition is switched through the valve of the test system, and heat is exchanged through the coupled heat exchanger, etc. Figure 4 As shown, the specific test mode in this embodiment includes the following test methods:

[0032] HVAC independent cooling performance test: turn on the compressor, open the solenoid valve, close the electronic expansion valve, and let the refrigerant return to the compressor after passing through the cooler, expansion valve, and evaporator. By adjusting the compressor speed, external ambient temperature, and fan speed, the HVAC independent performance test can be achieved.

[0033] Independent cooling performance test of the battery pack: turn on the compressor, close the solenoid valve, turn on the electronic expansion valve, and the refrigerant returns to the compressor after passing through the cooler, the electronic expansion valve, and the chiller refrigeration device. Turn on water pump 1, connect four-way valves 3-4, and the refrigerant and battery coolant exchange heat in the chiller refrigeration device. By adjusting the compressor speed, water pump speed, external ambient temperature, and fan speed, the independent performance of the battery pack can be tested.

[0034] Simultaneous cooling performance test of HVAC and battery pack: turn on the compressor, solenoid valve, electronic expansion valve, water pump 1, connect four-way valve 3-4, and the refrigerant cools the HVAC through the evaporator. The refrigerant exchanges heat with the battery coolant through the chiller. By adjusting the compressor speed and the opening of the electronic expansion valve, the cooling capacity and refrigerant flow are adjusted to achieve simultaneous cooling performance test of HVAC and battery pack.

[0035] Simultaneous cooling performance test of HVAC, battery pack, and motor: Turn on the compressor, solenoid valve, electronic expansion valve, water pump 1, water pump 2, three-way valve 1-2, four-way valve 1-2, 3-4, the refrigerant cools the HVAC through the evaporator, the refrigerant exchanges heat with the battery coolant through the chiller, and the motor coolant dissipates heat through the radiator. By adjusting the compressor speed, electronic expansion valve opening, external ambient temperature, water pump speed, and fan speed, the simultaneous cooling performance test of HVAC, battery pack, and motor is achieved.

[0036] HVAC heating performance test: Turn on the PTC heater and adjust the external ambient temperature and fan speed to perform the HVAC heating performance test.

[0037] Motor waste heat recovery performance test: turn on water pumps 1 and 2, connect three-way valves 1-3, connect four-way valves 1-3 and 2-4, and implement motor waste heat recovery performance test by adjusting motor speed, water pump speed, and external ambient temperature.

[0038] Example 2: An integrated thermal management performance test experiment for an electric vehicle

[0039] The integrated thermal management performance test principle of the electric vehicle in this embodiment is as follows Figure 5 As shown, for different thermal management system test requirements and working modes, the controller adjusts the status of the compressor, fan, water pump, and valve. The pressure sensor, temperature sensor, and flow meter installed in the test system are used to record the pressure, temperature, and flow data of the test object. The test data is processed to realize the analysis of the thermal management performance. The specific test methods include the following test methods:

[0040] HVAC refrigeration performance test method: In order to simulate the refrigeration condition under high temperature conditions in summer, the condenser inlet air temperature is controlled to maintain a certain high temperature (35℃) through a constant temperature and humidity chamber, and the evaporator inlet air temperature is maintained at a relatively low temperature (25℃). By maintaining the maximum inlet air volume of the evaporator, the performance of the system at different condenser inlet air speeds is tested respectively, and the compressor speed is proportional to it; in addition, the maximum inlet air volume of the condenser can be maintained, and the performance of the system at different evaporator near-wind speeds can be tested respectively. During the test, the air volume V of the evaporator is measured. F , the enthalpy h1 and h2 of the air flowing through the evaporator are calculated by using dry-bulb thermometers 1 and 2, and the calculation formula for the refrigeration capacity of HVAC is obtained as follows: Q ea =V F (h1-h2); In cooling mode, the refrigerant flow M is measured by the flow meter F , calculate the refrigerant enthalpy h before and after flowing through the condenser through pressure and temperature sensors in 、h out The heat transfer calculation formula of the condenser is: Q ca =M F ·(h in -h out ).

[0041] HVAC heating performance test method: In the heating mode, the PTC inside the HVAC is heated and the heat is blown into the cab by the blower. The main purpose is to test the PTC heating performance at different ambient temperatures. By keeping the HVAC inlet and outlet air volume at the maximum, the HVAC inlet and outlet temperatures at different ambient temperatures are tested. The HVAC air volume V F , the enthalpy h1 and h2 of the air flowing through the HVAC are calculated by using the dry-bulb thermometers 1 and 2, and the calculation formula for the heating capacity of the HVAC is obtained as follows: Q ra =V F ·(h2-h1).

[0042] Battery pack / motor cooling performance test method: In order to simulate the summer cooling environment, the temperature of the constant temperature and humidity chamber 2 is controlled to a certain high temperature (35°C), so that the condenser inlet air temperature, battery temperature, and motor temperature are all maintained at 35°C. By maintaining the maximum speed of water pump 1 / water pump 2, the performance of the system at different condenser inlet air speeds is tested respectively, where the compressor speed is proportional to it. During the test, the mass flow m passing through the battery pack cooling circuit / motor cooling circuit is measured by a flow meter, and the coolant temperature T before and after passing through the battery pack / motor is measured by a temperature sensor. in 、T out , the cooling capacity calculation formula of the battery pack / motor is: Q c = cm·(T in -T out ).

[0043] Motor waste heat recovery performance test method: In the motor waste heat heating mode, the heat of the motor is transferred to the battery through the coolant circulation loop. The main purpose is to test the performance of the motor waste heat heating the battery at different ambient temperatures. By keeping the water pumps 1 and 2 at the maximum speed, the inlet and outlet temperatures T of the battery coolant at different ambient temperatures are tested. in 、T out , the calculation formula for the motor waste heat utilization is: Q h =c m ·(T out -T in ).

[0044] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. An integrated thermal management performance test system for electric vehicles, Its characteristics are: It includes a test system loop and a constant temperature and humidity chamber; the test system loop is installed in the constant temperature and humidity chamber, and the constant temperature and humidity chamber is used to simulate different environmental conditions; The test system loop is provided with HVAC, battery pack, motor and controller, compressor, chiller refrigeration device, evaporator, condenser, radiator, pipeline, multiple valves and multiple water pumps. The pipeline is used to connect the test system loop, multiple valves are installed on the pipeline to control the connection and disconnection of the pipeline, and multiple water pumps are installed in the pipeline to adjust the flow of coolant; The performance testing system also includes multiple fans, multiple thermometers, multiple flow meters and multiple pressure sensors; multiple fans are used to adjust the air flow inside the system, multiple thermometers are used to measure the air temperature flowing through the system and the refrigerant temperature flowing through the pipeline, multiple flow meters are used to measure the air flow flowing through the system or the refrigerant flow flowing through the pipeline, and multiple pressure sensors are used to measure the coolant pressure flowing through the pipeline.

2. An integrated thermal management performance testing system for electric vehicles according to claim 1, Its characteristics are: The multiple valves include electronic expansion valves, three-way valves and four-way valves respectively. The different valves are switched to realize performance testing of different thermal management performance testing subsystems, and can perform performance testing on thermal management performance testing subsystems that operate independently and in an integrated manner.

3. An integrated thermal management performance testing system for electric vehicles according to claim 2, Its characteristics are: The thermal management performance test subsystems include an HVAC independent cooling performance test subsystem, a battery pack independent cooling performance test subsystem, an HVAC and battery pack simultaneous cooling performance test subsystem, an HVAC, battery pack and motor simultaneous cooling performance test subsystem, an HVAC heating performance test subsystem, and a motor waste heat recovery performance test subsystem.

4. The integrated thermal management performance testing system for electric vehicles according to claim 1, Its characteristics are: The constant temperature and humidity chamber specifically includes a constant temperature and humidity chamber 1 and a constant temperature and humidity chamber 2, the HVAC is installed in the constant temperature and humidity chamber 1, the battery pack, the motor and the controller, the condenser and the radiator are installed in the constant temperature and humidity chamber 2, and the HVAC is connected with the battery pack, the motor and the controller, the condenser and the radiator through pipelines to form a test system loop.

5. The integrated thermal management performance testing method of an electric vehicle according to claim 1, Its characteristics are: The following steps are involved: S1. Control the temperature and humidity of the internal environment of the performance test system through a constant temperature and humidity chamber; S2. Using a fan to adjust the air flow inside the performance test system; S3. Use a thermometer to measure the air temperature flowing through the system and the refrigerant temperature flowing through the pipeline, a flow meter to measure the air flow rate flowing through the system or the refrigerant flow rate flowing through the pipeline, and a pressure sensor to measure the coolant pressure flowing through the pipeline to obtain specific values ​​of the performance test system. S4. Obtain the performance data of the performance test system through specific numerical calculations, thereby completing the integrated thermal management performance test.

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