In-loop energy flow test method and system of electric drive system

Abstract

The invention relates to an in-loop energy flow testing method and system of an electric drive system. The in-loop energy flow test system comprises a whole vehicle model HIL system, an electric drive system test bench, a high-low voltage power supply system and a main control system, the in-loop energy flow test system is further provided with a sensor, and the electric drive system test bench is provided with an electric drive system to be tested; wherein the driving working condition parameters of the whole vehicle model HIL system are configured, a real vehicle is simulated to generate a control signal, the control signal is sent to the electric drive system, and the electric drive system is indicated to execute corresponding actions; the high-low voltage power supply system supplies power to the electric drive system; the master control system is used for synchronizing the state of the whole vehicle model HIL system and the state of the electric drive system. Acquiring operation data of the electric drive system through a sensor; and evaluating the performance index of the electric drive system according to the operation data to obtain an energy flow test result. According to the method, the electric drive system is tested in a virtual-real combination mode, the dependence on field road testing can be reduced, and the testing efficiency, the testing precision and the testing reliability are improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle testing technology, and in particular to an in-loop energy flow testing method and system for an electric drive system. Background Art

[0002] The electric drive system is a highly integrated and complex system. The multiple components of the electric drive system will interact and influence each other when working, making energy and efficiency testing extremely complicated. At the same time, the performance of the electric drive system varies greatly under different working conditions, and it is necessary to simulate multiple (transient or steady-state) working conditions and usage scenarios for testing, which further increases the complexity of energy or efficiency testing.

[0003] At present, the energy or efficiency test of the electric drive system is generally carried out through real vehicle testing or bench testing. However, real vehicle testing cannot be carried out during the development stage of the electric drive system, and the assembly performance cannot be optimized in advance. In the bench test, since only the electric drive system is placed separately, the factors affecting the operation of the electric drive system in the whole vehicle are often ignored, and the energy or efficiency test results cannot truly reflect the actual situation of the electric drive system in the operation of the whole vehicle. In addition, under low-speed and low-torque operating conditions, the accuracy of the bench test will decrease, further leading to reduced test accuracy. Summary of the invention

[0004] Based on this, it is necessary to provide an in-loop energy flow testing method and system for an electric drive system to address the above-mentioned technical problems. The electric drive system can be tested in a combination of virtual and real ways, which can reduce dependence on field road testing and improve the efficiency, accuracy and reliability of energy flow testing.

[0005] In a first aspect, the present application provides an in-loop energy flow test method for an electric drive system, the method being applied to the in-loop energy flow test system, the in-loop energy flow test system comprising a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system, and a main control system, the in-loop energy flow test system is also equipped with a sensor, and the electric drive system test bench is equipped with an electric drive system to be tested; the method comprises:

[0006] Configure the driving condition parameters of the vehicle model HIL system so that the vehicle model HIL system simulates the real vehicle, generates control signals according to the driving condition parameters, and sends the control signals to the electric drive system; the control signals are used to instruct the electric drive system to perform corresponding actions; the high and low voltage power supply systems supply power to the electric drive system; the main control system is used to synchronize the status of the vehicle model HIL system and the electric drive system;

[0007] Obtain the operating data of the electric drive system through sensors;

[0008] Based on the operating data, the performance indicators of the electric drive system are evaluated and the energy flow test results are obtained.

[0009] In one embodiment, the performance index includes energy efficiency; the sensor includes a speed torque sensor and a first current sensor; the electric drive system to be tested includes a motor controller, a drive motor and a main reducer; the speed torque sensor is installed at the output end of the main reducer, and the first current sensor is installed at the input end of the motor controller;

[0010] Based on the operating data, the performance indicators of the electric drive system are evaluated, including:

[0011] Determining the input power of the electric drive system according to the input current collected by the first current sensor;

[0012] Determine the output power of the electric drive system according to the output torque and output speed collected by the speed torque sensor;

[0013] Evaluate the energy efficiency of the electric drive system based on input power and output power.

[0014] In one embodiment, the performance indicator further includes an energy flow state; the sensor further includes a second current sensor; the motor controller further includes an inverter; the second current sensor is installed at a three-phase output terminal of the inverter;

[0015] The method further comprises:

[0016] Determine the output power of the inverter according to the three-phase current collected by the second current sensor;

[0017] Calculate the electromagnetic power of the drive motor;

[0018] The energy flow state of the electric drive system is evaluated based on the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor, and the output power of the electric drive system.

[0019] In one embodiment, the performance index further includes a cooling performance index; the electric drive system to be tested further includes a cooling system; the motor controller is used to adjust the working state of the cooling system according to the motor output state; the sensor further includes a temperature sensor, and the temperature sensor is used to detect the coolant inlet temperature and the coolant outlet temperature of the cooling system;

[0020] Based on the operating data, the performance indicators of the electric drive system are evaluated, including:

[0021] Determine the heat dissipation power of the cooling system according to the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor;

[0022] Evaluate the cooling performance indicators of the electric drive system based on the heat dissipation power.

[0023] In a second aspect, the present application also provides an in-loop energy flow test system for an electric drive system, the system comprising a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system, a main control system and an analysis device, the system is also equipped with a sensor, and the electric drive system test bench is equipped with an electric drive system to be tested;

[0024] The vehicle model HIL system is used to simulate the real vehicle, generate control signals according to driving condition parameters, and send the control signals to the electric drive system;

[0025] An electric drive system, used to perform corresponding actions according to control signals;

[0026] High and low voltage power supply systems, used to power the electric drive system;

[0027] The main control system is used to synchronize the status of the vehicle model HIL system and the electric drive system;

[0028] Sensors are used to collect operating data of the electric drive system and transmit the operating data to the analysis equipment through the main control system;

[0029] Analysis equipment is used to evaluate the performance indicators of the electric drive system based on the operating data and obtain the energy flow test results.

[0030] In one embodiment, the performance index includes energy efficiency; the sensor includes a speed torque sensor and a first current sensor; the electric drive system to be tested includes a motor controller, a drive motor and a main reducer; the speed torque sensor is installed at the output end of the main reducer, and the first current sensor is installed at the input end of the motor controller;

[0031] The analysis device is also used to determine the input power of the electric drive system based on the input current collected by the first current sensor; determine the output power of the electric drive system based on the output torque and output speed collected by the speed and torque sensor; and evaluate the energy efficiency of the electric drive system based on the input power and output power.

[0032] In one embodiment, the performance indicator further includes an energy flow state; the sensor further includes a second current sensor; the motor controller further includes an inverter; the second current sensor is installed at a three-phase output terminal of the inverter;

[0033] The analysis device is also used to determine the output power of the inverter based on the three-phase current collected by the second current sensor; calculate the electromagnetic power of the drive motor; and evaluate the energy flow state of the electric drive system based on the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor, and the output power of the electric drive system.

[0034] In one embodiment, the performance index further includes a cooling performance index; the electric drive system to be tested further includes a cooling system; the motor controller is used to adjust the working state of the cooling system according to the motor output state; the sensor further includes a temperature sensor, and the temperature sensor is used to detect the coolant inlet temperature and the coolant outlet temperature of the cooling system;

[0035] The analysis equipment is also used to determine the heat dissipation power of the cooling system based on the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor; and to evaluate the cooling performance index of the electric drive system based on the heat dissipation power.

[0036] In one of the embodiments, the high and low voltage power supply system includes high and low voltage load boxes and high and low voltage battery simulators;

[0037] High and low voltage load boxes are used to simulate the electrical load during vehicle operation;

[0038] High and low voltage battery simulators, used to supply power to high and low voltage load boxes;

[0039] The high and low voltage load boxes are also used to power the electric drive system based on the electrical load with the support of the high and low voltage battery simulators.

[0040] In one embodiment, the vehicle model HIL system includes a vehicle model and a vehicle controller model;

[0041] The vehicle model is used to simulate the real vehicle and generate pedal requirements based on driving condition parameters;

[0042] The vehicle controller model is used to calculate the torque demand of the drive motor according to the pedal demand and the vehicle state, and generate a control signal according to the torque demand.

[0043] The above-mentioned in-loop energy flow test method and system of the electric drive system, the in-loop energy flow test system includes a whole vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system and a main control system, the in-loop energy flow test system is also equipped with a sensor, and the electric drive system test bench is installed with the electric drive system to be tested; wherein, the driving condition parameters of the whole vehicle model HIL system are configured so that the whole vehicle model HIL system simulates a real vehicle, generates a control signal according to the driving condition parameters, and sends the control signal to the electric drive system; the control signal is used to instruct the electric drive system to perform the corresponding action; the high and low voltage power supply system supplies power to the electric drive system; the main control system is used to synchronize the status of the whole vehicle model HIL system and the electric drive system; through sensors, the operating data of the electric drive system is obtained; according to the operating data, the performance indicators of the electric drive system are evaluated to obtain the energy flow test results. The present application adopts a combination of virtual and real methods to test the electric drive system. Through the whole vehicle model HIL system, various driving conditions can be widely simulated to fully verify the performance and stability of the electric drive system under various conditions. The use of an electric drive system test bench can achieve vehicle-level integrated testing during the development phase of the electric drive system, optimize assembly performance in advance, reduce reliance on field road testing, and improve energy flow testing efficiency. By setting up high and low voltage power supply systems and a main control system, it is ensured that the various components of the electric drive system work together in a vehicle environment, improving the accuracy and reliability of energy flow testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] FIG1 is a schematic flow chart of an in-loop energy flow test method for an electric drive system in one embodiment;

[0046] FIG2 is a block diagram of an in-loop energy flow test system for an electric drive system according to an embodiment;

[0047] FIG3 is a schematic flow chart of an in-loop energy flow testing method for an electric drive system in another embodiment;

[0048] FIG4 is a structural block diagram of an in-loop energy flow test system for an electric drive system in another embodiment;

[0049] FIG. 5 is a diagram showing the internal structure of an analysis device in one embodiment. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0051] In an exemplary embodiment, as shown in FIG1 , a method for in-the-loop energy flow testing of an electric drive system is provided, the method being applied to the in-the-loop energy flow testing system, the in-the-loop energy flow testing system comprising a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system and a main control system, the in-the-loop energy flow testing system is also equipped with a sensor, and the electric drive system test bench is equipped with an electric drive system to be tested; the method comprising:

[0052] Step 102, configure the driving condition parameters of the whole vehicle model HIL system so that the whole vehicle model HIL system simulates the real vehicle, generates a control signal according to the driving condition parameters, and sends the control signal to the electric drive system; the control signal is used to instruct the electric drive system to perform corresponding actions; the high and low voltage power supply systems supply power to the electric drive system; the main control system is used to synchronize the status of the whole vehicle model HIL system and the electric drive system.

[0053] Step 104, obtaining the operation data of the electric drive system through sensors.

[0054] Step 106, evaluating the performance indicators of the electric drive system according to the operating data, and obtaining the energy flow test results.

[0055] 2, the in-loop energy flow test system includes a vehicle model HIL system 201, an electric drive system test bench 202, a high and low voltage power supply system 203, and a main control system 204. The vehicle model HIL (hardware in the loop) system 201 is used to simulate the driving conditions of a real vehicle on an actual road, including road resistance, vehicle dynamics characteristics, and vehicle energy flow. By simulating the interaction of driver operation, vehicle power transmission, and the environment, a close-to-real cyclic working environment is provided for the electric drive system.

[0056] The electric drive system test bench 202 is used to provide the necessary working environment for the new energy electric drive system to be tested. The electric drive system test bench may include a motor controller, a drive motor and a main reducer, a cooling system (oil circulation, water circulation, oil-water heat exchanger), and high and low voltage system wiring. The electric drive system test bench can simulate various working conditions of the electric drive system in the actual operation of the vehicle and monitor its dynamics, temperature rise and power performance.

[0057] The high and low voltage power supply system 203 is used to provide high voltage and low voltage electricity that meet the working requirements of the electric drive system to support the normal operation of the high voltage components and low voltage components in the whole vehicle system under the real test environment. It can also simulate the electrical load of the whole vehicle in actual operation to ensure the integrity and accuracy of the system test.

[0058] The main control system 204 is responsible for data communication between the vehicle model HIL system 201 and the electric drive system test bench 202 to ensure system synchronization and real-time performance.

[0059] It is understandable that the driving condition parameters include the vehicle's dynamic parameters, road conditions, driving cycles, etc. The vehicle model HIL system can simulate the driving process of the real vehicle based on the driving condition parameters, determine the torque demand, and generate a control signal to send to the electric drive system. During the test operation of the electric drive system, various operating indicators are collected through pre-installed sensors to obtain operating data, including current, voltage, temperature, motor speed, etc. By analyzing the operating data, the performance indicators of the electric drive system are evaluated to obtain the energy flow test results. The performance indicators include energy efficiency, energy flow status, cooling performance indicators, etc.

[0060] Optionally, the method further includes: recording the operating data corresponding to different driving condition parameters according to the time information to obtain the operating data sequences corresponding to the multiple driving conditions; performing performance evaluation and fault analysis according to the operating data sequences corresponding to the multiple driving conditions to obtain analysis results; and optimizing the control strategy of the electric drive system according to the analysis results. In particular, the operating data during the test is collected and saved according to the time information, and subsequent performance evaluation and fault analysis are performed, and the configuration and control strategy of the electric drive system are optimized according to the analysis results to improve the efficiency and reliability of the system.

[0061] In an optional implementation, the in-loop energy flow test method of the electric drive system includes the following steps:

[0062] 1. Test preparation:

[0063] The driving condition parameters of the whole vehicle model HIL system are set, including the vehicle's dynamic parameters, road conditions, driving cycles, etc.; in this embodiment, the whole vehicle model HIL system can simulate regulatory cycle energy flow tests such as CLTC (China Automotive Test Cycle), WLTC (World Light Vehicle Test Procedure) or NEDC (New European Driving Cycle); prepare an electric drive system test bench to ensure that key components such as the drive motor, inverter, and cooling system are connected and in working condition; install necessary sensors, such as current sensors, temperature sensors, position sensors, etc., to monitor the system's operating data.

[0064] 2. System initialization:

[0065] Start the main control system and perform a system self-check to ensure that all components are working properly; activate the high and low voltage power supply systems to provide the required operating voltage for the electric drive system; synchronize the status of the vehicle model HIL system and the electric drive system test bench through the main control system.

[0066] 3. Test execution:

[0067] According to the preset driving cycle, the vehicle model starts to simulate vehicle driving and generates accelerator pedal and brake pedal requirements; the vehicle controller model calculates the torque and power requirements of the drive motor based on the pedal requirements and vehicle status, and generates a control signal to the motor controller; the motor controller model converts the torque and power requirements carried in the control signal into a motor control signal, driving the motor to generate corresponding output; the electric drive system test bench adjusts the cooling system and power supply according to the actual output of the motor to ensure stable operation of the system.

[0068] 4. Data collection and monitoring:

[0069] The arranged sensors collect the operating data of the electric drive system in real time, including current, voltage, temperature, motor speed, etc.; the monitoring data is transmitted to the vehicle model HIL system through the main control system for further analysis and processing; the response of the electronic load in the high and low voltage power supply system is observed to ensure that it can accurately simulate the electrical characteristics of the high-voltage battery and drive motor.

[0070] 5. Test completion and analysis:

[0071] After completing the test sequence, shut down the electric drive system test bench and the vehicle model HIL system; collect and save the test data for subsequent performance evaluation and fault analysis; optimize the configuration and control strategy of the electric drive system based on the test results to improve the efficiency and reliability of the system.

[0072] It should be noted that by performing the energy flow test of the electric drive system in the manner of the embodiment of the present application, the performance of the electric drive system can be comprehensively and accurately evaluated in a laboratory environment, reducing the need for actual road testing, especially in the initial R&D stage, the electric drive system level can be continuously tested without being affected by the external environment, thereby improving R&D efficiency. Testing in a laboratory environment can more safely evaluate the performance of the electric drive system under extreme working conditions and ensure the safety of the electric drive system. Through the close cooperation between the whole vehicle model HIL system and the electric drive system test bench, the working conditions of the electric drive system in actual driving can be simulated in real time; when a large number of repeated tests are required, the whole vehicle model HIL system can be used to automatically repeat the same test, thereby greatly improving the test efficiency. The virtual-real combined test system is not limited by the physical environment and actual operation, and can widely simulate various driving conditions, increase the test coverage, and fully verify the performance and stability of the electric drive system under various conditions. In addition, the energy flow test results provide strong data support for the optimization and improvement of the electric drive system, which helps to improve the performance and reliability of the product. Based on the detailed energy flow test data, engineers can have a deeper understanding of the working characteristics and bottlenecks of the electric drive system, thereby promoting innovation and optimization in technology and design.

[0073] In the above-mentioned in-loop energy flow test method of the electric drive system, a combination of virtual and real methods is used to test the electric drive system. Through the whole vehicle model HIL system, various driving conditions can be widely simulated to fully verify the performance and stability of the electric drive system under various conditions. The use of an electric drive system test bench can achieve vehicle-level integrated testing during the development stage of the electric drive system, optimize assembly performance in advance, reduce dependence on field road testing, and improve energy flow testing efficiency. By setting up high and low voltage power supply systems and a main control system, it is ensured that the various components of the electric drive system work together in a whole vehicle environment, thereby improving the accuracy and reliability of energy flow testing.

[0074] In an exemplary embodiment, the performance index includes energy efficiency; the sensor includes a speed torque sensor and a first current sensor; the electric drive system to be tested includes a motor controller, a drive motor and a main reducer; the speed torque sensor is installed at the output end of the main reducer, and the first current sensor is installed at the input end of the motor controller;

[0075] Step 106 includes: determining the input power of the electric drive system according to the input current collected by the first current sensor; determining the output power of the electric drive system according to the output torque and output speed collected by the speed torque sensor; and evaluating the energy efficiency of the electric drive system according to the input power and the output power.

[0076] Among them, a speed and torque sensor is arranged at the output end of the main reducer to measure the speed and torque output of the main reducer in real time. Its test precision control and synchronous signal transmission are crucial, especially in the dynamic test of the whole vehicle. It can be understood that the speed and torque signals of the speed and torque sensor are used as the source of energy flow analysis and calculation on the one hand, and as feedback signals on the other hand, they are transmitted to the vehicle model HIL system in real time to realize the closed loop of simulation signals.

[0077] The first current sensor is arranged at the input end of the motor controller to monitor the current state of the high and low voltage power supply systems to the motor controller in real time, so as to ensure the real-time measurement of the input energy of the electric drive system in the energy flow test.

[0078] It is understandable that the high and low voltage power supply system is provided with a voltage detection unit, which can determine the DC voltage, and the input power of the electric drive system can be determined based on the DC voltage and the input current collected by the first current sensor. The mechanical power, that is, the output power of the electric drive system, can be determined based on the output torque and output speed collected by the speed torque sensor. The energy efficiency of the electric drive system is evaluated based on the input power and output power.

[0079] In this embodiment, high-precision sensors and advanced data acquisition systems are used to ensure the accuracy and reliability of test data; key parameters of the electric drive system can be acquired in real time and accurately, thereby evaluating the energy efficiency of the electric drive system; and the electrical, mechanical and other aspects of the electric drive system are comprehensively considered to comprehensively evaluate the performance of the system.

[0080] In an exemplary embodiment, the performance indicator further includes an energy flow state; the sensor further includes a second current sensor; the motor controller further includes an inverter; the second current sensor is installed at a three-phase output terminal of the inverter;

[0081] The method also includes: determining the output power of the inverter based on the three-phase current collected by the second current sensor; calculating the electromagnetic power of the drive motor; and evaluating the energy flow state of the electric drive system based on the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor, and the output power of the electric drive system.

[0082] The second current sensor is composed of three current sensors, which are installed at the three-phase output ends of the inverter UVW to detect the output current of each phase. Optionally, two current sensors can be used to detect the output current of two phases, and the output current of the third phase can be calculated by software algorithm. The data collected by the second current sensor can be used to achieve closed-loop control of the electric drive system and ensure that it works as expected.

[0083] In an optional implementation, the drive motor can be a permanent magnet synchronous motor (PMSM), which works on a principle involving multiple conversion steps from a direct current (DC) input source to a mechanical output. The following is a detailed description of these conversion steps, involving the input power of the electric drive system (also known as the DC input power), the output power of the inverter (also known as the three-phase AC power), the electromagnetic power of the drive motor, and the output power of the electric drive system (also known as the mechanical power):

[0084] 1. The electric drive system is usually powered by a DC power supply, such as a battery or other DC power supply. This DC power supply powers the permanent magnet synchronous motor through an inverter. The main function of the inverter is to convert DC power into three-phase AC power. The DC input power can be expressed as: ,in is the DC voltage, is the current flowing out of the DC source.

[0085] 2. The inverter converts DC into three-phase AC. This conversion involves voltage and current conversion and certain losses. Assuming the efficiency of the inverter is η, the three-phase AC output power is: , three-phase AC power can also be expressed by AC output parameters: ,in, is the line voltage, is the line current and φ is the phase difference.

[0086] 3. The three-phase alternating current generates a rotating magnetic field through the stator winding of the motor. This rotating magnetic field interacts with the magnetic field generated by the permanent magnet to generate electromagnetic torque. Electromagnetic power is the actual electrical power absorbed by the motor, minus the internal losses of the motor (such as copper loss and iron loss). It can be expressed as: .

[0087] 4. Electromagnetic torque is converted into mechanical torque and transmitted to the mechanical system through the motor shaft. Mechanical power is the actual power output by the motor and can be calculated using the following formula: ,in is the angular velocity (radians per second), and T is the torque generated by the motor. It is understood that the torque T generated by the motor can be measured by a sensor.

[0088] Alternatively, the electromagnetic torque (torque) of a permanent magnet synchronous motor (PMSM) is generated by the interaction of the magnetic fields between the permanent magnets and the stator windings. To calculate the electromagnetic torque of a permanent magnet synchronous motor, the following basic formula can be used:

[0089] ;

[0090] Where T is the electromagnetic torque (Newton meters), p is the number of pole pairs of the motor, is the flux produced by the permanent magnet (Weber), is the stator q-axis current (amperes), is the stator d-axis current (amperes), which may be set to zero in some control strategies to optimize efficiency, is the inductance of the motor's d-axis (henry). This formula is for ideal situations and may need to be adjusted in practice based on the motor's specific parameters and operating conditions. In addition, the motor's control strategy (such as vector control or direct torque control) will also affect the actual torque generation. When designing and commissioning permanent magnet synchronous motors, it is usually necessary to accurately calculate the electromagnetic torque through experimental measurements or detailed simulations. The electromagnetic power can be determined by multiplying the electromagnetic torque with the angular velocity measured by the sensor .

[0091] In an exemplary embodiment, the performance index further includes a cooling performance index; the electric drive system to be tested further includes a cooling system; the motor controller is used to adjust the working state of the cooling system according to the motor output state; the sensor further includes a temperature sensor, and the temperature sensor is used to detect the coolant inlet temperature and the coolant outlet temperature of the cooling system;

[0092] Step 106 includes: determining the heat dissipation power of the cooling system according to the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor; and evaluating the cooling performance index of the electric drive system according to the heat dissipation power.

[0093] Wherein, coolant refers to at least one of water or oil. Optionally, in order to detect the thermal performance of the electric drive cooling system, temperature sensors are arranged at the inlet and outlet of the water circulation and oil circulation systems, which, on the one hand, helps to ensure that the system operates within a safe and effective temperature range; on the other hand, the obtained water temperature and oil temperature signals, combined with the oil and water flow signals, can be used to perform energy flow analysis and calculation under specific operating conditions for the electric drive cooling system.

[0094] In an optional implementation, the drive motor may be a permanent magnet synchronous motor, and its temperature test may be used to evaluate the efficiency of the cooling system, for example, measuring the cooling oil heat dissipation power. This test can help ensure that the motor operates within a safe and effective temperature range, thereby extending its life and improving performance. The steps of using the temperature test to obtain the cooling oil heat dissipation power include:

[0095] Set up temperature sensors (such as thermocouples or RTDs) and flow meters. Install temperature sensors at the inlet and outlet of the cooling oil to measure the inlet and outlet temperatures of the cooling oil, and install flow meters at appropriate locations to measure the flow rate of the cooling oil.

[0096] During motor operation, record the inlet temperature of the cooling oil and outlet temperature At the same time, record the cooling oil flow during this period (mass flow rate, usually expressed in kilograms per second).

[0097] The heat dissipation power of the cooling oil can be calculated by the following formula:

[0098] ;

[0099] in, is the specific heat capacity of the cooling oil (in joules / kg·°C), and are the outlet and inlet temperatures of the cooling oil (in degrees Celsius), is the mass flow rate of cooling oil.

[0100] Similarly, by measuring the inlet temperature, outlet temperature and mass flow rate of the cooling water, the heat dissipation power of the cooling water can be calculated.

[0101] Optionally, the heat dissipation power of the cooling system is determined by combining the heat dissipation power of the cooling oil and the heat dissipation power of the cooling water; and the cooling performance index of the electric drive system is evaluated based on the heat dissipation power. The specific evaluation criteria can be set according to the design parameters of the electric drive system.

[0102] In this embodiment, the electrical, mechanical, thermal and other aspects of the electric drive system are comprehensively considered, so that the performance of the system can be fully evaluated, and the accuracy and reliability of the energy flow test are improved.

[0103] In an optional implementation, referring to FIG. 3 , a method for testing an in-loop energy flow of an electric drive system is proposed, comprising the following steps:

[0104] 1. Test preparation, including parameter setting, preparation of the electric drive system test bench, and sensor installation. According to the test requirements, set the driving condition parameters of the whole vehicle model in the whole vehicle model HIL system, including vehicle mass, air resistance, rolling resistance, etc. Install the electric drive system to be tested on the electric drive system test bench, and ensure that all electrical and mechanical connections are correct. Install current, temperature, speed and torque sensors at key locations such as the motor controller input, motor three-phase input, main reducer output, cooling system inlet and outlet.

[0105] 2. System initialization, including: starting the test bench main control system and performing self-checks to ensure that all components are working properly; starting the high-voltage battery simulator and the low-voltage battery simulator to provide the required operating voltage for the electric drive system; synchronizing the real-time vehicle model with the status of the electric drive system test bench through the test bench main control system.

[0106] 3. Test execution, including driving cycle simulation, control signal calculation, motor control, and system adjustment. The real-time vehicle model starts to simulate vehicle driving according to the preset driving cycle and generates accelerator pedal and brake pedal requirements; the vehicle controller model calculates the torque and power requirements of the drive motor according to the pedal requirements and vehicle status, and generates control signals to the motor controller; the motor controller converts the torque and power requirements into motor control signals to drive the motor to generate corresponding outputs; the electric drive system test bench adjusts the cooling system and power supply according to the actual output of the motor to ensure stable operation of the system.

[0107] 4. Data collection and monitoring, including data collection, load monitoring and data transmission. The operating data of the electric drive system, including current, voltage, temperature, motor speed, etc., are collected in real time through the arranged sensors; the response of the electronic load is monitored to ensure that it accurately simulates the electrical characteristics of the high-voltage battery and drive motor; the collected monitoring data is transmitted to the real-time vehicle model through the main control system for analysis and processing.

[0108] 5. Test completion and analysis, specifically including: after completing the test sequence, shut down the electric drive system test bench and the vehicle model HIL system; collect and save test data for subsequent performance evaluation and fault analysis; based on the test results, evaluate the electric drive system's key performance indicators such as energy flow, operating cycle efficiency, temperature rise, dynamic response, and output test results, including various performance indicators and energy flow analysis reports; based on the test results, optimize and improve the configuration and control strategy of the electric drive system to improve the efficiency and reliability of the system.

[0109] Optionally, define in advance the hardware interface and software algorithm for state synchronization between the vehicle model HIL system and the electric drive system test bench, and define the format and protocol for data exchange between the two to ensure the accuracy and real-time performance of data transmission; pre-configure the fault detection and recovery mechanism of the synchronization process to ensure the continuity and stability of the test.

[0110] Optionally, set the frequency and timing of data collection to ensure the real-time and integrity of the data; set the data processing and analysis method to process the raw data collected by the sensor into detailed data of performance evaluation indicators. Set up a system feedback adjustment mechanism: Based on the data processing results, adjust the electric drive system in real time to optimize the test process.

[0111] Optionally, multiple driving cycle models are set, and accelerator pedal and brake pedal requirements are generated according to the driving cycle models to simulate different driving conditions and environments, ensuring the real-time performance of the driving cycle simulation to accurately simulate the actual driving of the vehicle.

[0112] In this embodiment, the cooling system is adjusted according to the actual output of the motor to ensure the stability of the electric drive system during the test; the power supply is managed to meet the needs of the electric drive system under different test conditions; and it is ensured that the electric drive system can operate stably and is not interfered by external factors during the entire test process.

[0113] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0114] Based on the same inventive concept, the embodiment of the present application also provides an in-loop energy flow test system for an electric drive system for implementing the in-loop energy flow test method for the electric drive system involved above. The implementation scheme for solving the problem provided by the system is similar to the implementation scheme recorded in the above method, so the specific limitations in the embodiments of the in-loop energy flow test system for one or more electric drive systems provided below can be found in the above limitations on the in-loop energy flow test method for the electric drive system, and will not be repeated here.

[0115] In an exemplary embodiment, an in-loop energy flow test system for an electric drive system is provided, the system comprising a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system, a main control system and an analysis device, the system is also equipped with a sensor, and the electric drive system test bench is equipped with an electric drive system to be tested;

[0116] The vehicle model HIL system is used to simulate the real vehicle, generate control signals according to driving condition parameters, and send the control signals to the electric drive system;

[0117] An electric drive system, used to perform corresponding actions according to control signals;

[0118] High and low voltage power supply systems, used to power the electric drive system;

[0119] The main control system is used to synchronize the status of the vehicle model HIL system and the electric drive system;

[0120] Sensors are used to collect operating data of the electric drive system and transmit the operating data to the analysis equipment through the main control system;

[0121] Analysis equipment is used to evaluate the performance indicators of the electric drive system based on the operating data and obtain the energy flow test results.

[0122] The analysis device may be a computer device located at a remote end or a computer device running a vehicle model HIL system, and this embodiment does not limit this. For the description of the in-loop energy flow test system for the electric drive system, please refer to the specific explanation in the method embodiment of this application.

[0123] In the in-loop energy flow test system of the above-mentioned electric drive system, a combination of virtual and real methods is used to test the electric drive system. Through the whole vehicle model HIL system, various driving conditions can be widely simulated to fully verify the performance and stability of the electric drive system under various conditions. The use of an electric drive system test bench can achieve vehicle-level integrated testing during the development stage of the electric drive system, optimize assembly performance in advance, reduce dependence on field road testing, and improve energy flow testing efficiency. By setting up high and low voltage power supply systems and a main control system, it is ensured that the various components of the electric drive system work together in a whole vehicle environment, thereby improving the accuracy and reliability of energy flow testing.

[0124] In an exemplary embodiment, the performance index includes energy efficiency; the sensor includes a speed torque sensor and a first current sensor; the electric drive system to be tested includes a motor controller, a drive motor and a main reducer; the speed torque sensor is installed at the output end of the main reducer, and the first current sensor is installed at the input end of the motor controller;

[0125] The analysis device is also used to determine the input power of the electric drive system based on the input current collected by the first current sensor; determine the output power of the electric drive system based on the output torque and output speed collected by the speed and torque sensor; and evaluate the energy efficiency of the electric drive system based on the input power and output power.

[0126] In an exemplary embodiment, the performance indicator further includes an energy flow state; the sensor further includes a second current sensor; the motor controller further includes an inverter; the second current sensor is installed at a three-phase output terminal of the inverter;

[0127] The analysis device is also used to determine the output power of the inverter based on the three-phase current collected by the second current sensor; calculate the electromagnetic power of the drive motor; and evaluate the energy flow state of the electric drive system based on the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor, and the output power of the electric drive system.

[0128] In an exemplary embodiment, the performance index further includes a cooling performance index; the electric drive system to be tested further includes a cooling system; the motor controller is used to adjust the working state of the cooling system according to the motor output state; the sensor further includes a temperature sensor, and the temperature sensor is used to detect the coolant inlet temperature and the coolant outlet temperature of the cooling system;

[0129] The analysis equipment is also used to determine the heat dissipation power of the cooling system based on the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor; and to evaluate the cooling performance index of the electric drive system based on the heat dissipation power.

[0130] In an exemplary embodiment, the high and low voltage power supply system includes high and low voltage load boxes and high and low voltage battery simulators;

[0131] High and low voltage load boxes are used to simulate the electrical load during vehicle operation;

[0132] High and low voltage battery simulators, used to supply power to high and low voltage load boxes;

[0133] The high and low voltage load boxes are also used to power the electric drive system based on the electrical load with the support of the high and low voltage battery simulators.

[0134] It can be understood that, with reference to FIG4 , the in-loop energy flow test system of the electric drive system provided in the present application includes a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system, a main control system (not shown in FIG4 ) and an analysis device (not shown in FIG4 ). The high and low voltage load boxes are used to simulate the battery management system, high voltage battery, low voltage battery, low voltage DC / DC, high voltage junction box and other electrical loads of the vehicle in actual operation to ensure the integrity and accuracy of the system test. The high and low voltage battery simulators include a high voltage battery simulator and a low voltage battery simulator, which respectively provide high voltage electricity and low voltage electricity that meet the working requirements of the electric drive system to support the normal operation of the high voltage components and low voltage components in the vehicle system under a real test environment.

[0135] In an exemplary embodiment, a full vehicle model HIL system includes a vehicle model and a vehicle controller model;

[0136] The vehicle model is used to simulate the real vehicle and generate pedal requirements based on driving condition parameters;

[0137] The vehicle controller model is used to calculate the torque demand of the drive motor according to the pedal demand and the vehicle state, and generate a control signal according to the torque demand.

[0138] Wherein, referring to FIG4, the vehicle model HIL system includes a vehicle model and a vehicle controller model; the vehicle model is composed of a driver model, a vehicle system, a brake system, and a tire. The driver model is used to simulate the changes of the accelerator pedal and the brake pedal during the actual driving of the vehicle. By receiving the target vehicle speed and the actual vehicle speed under the operating conditions, the accelerator pedal and the brake pedal instructions are output through model settlement. The vehicle system, the brake system, and the tire are used to simulate the basic mechanical relationship of the vehicle dynamics, taking into account the influence of wind resistance, slope resistance, and road surface on the vehicle, and according to the torque signal received by the transmission shaft, combined with the vehicle dynamic characteristics and road surface characteristic parameters, calculate and output the current speed, torque and other information of the vehicle. The vehicle controller model calculates the torque demand according to the pedal demand and the vehicle state, and generates a control signal to send to the motor controller. The motor controller converts the torque demand (or torque demand and power demand) into a motor control signal to drive the motor to generate the corresponding output.

[0139] In an optional implementation, referring to Figure 4, the in-loop energy flow test system of the electric drive system also includes a dynamometer controller, which has control, calculation, recording and other functions. Its function is to simulate the changes in the drive system load based on the speed output by the HIL system of the whole vehicle model, so as to facilitate testing under various driving conditions.

[0140] In an exemplary embodiment, an analysis device is provided, which may be a server, and its internal structure diagram may be shown in FIG5. The analysis device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the analysis device is used to provide computing and control capabilities. The memory of the analysis device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the analysis device is used to exchange information between the processor and an external device. The communication interface of the analysis device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, an in-loop energy flow test method for an electric drive system is implemented.

[0141] Those skilled in the art will understand that the structure shown in FIG. 5 is merely a block diagram of a partial structure related to the scheme of the present application, and does not constitute a limitation on the analysis device to which the scheme of the present application is applied. The specific analysis device may include more or fewer components than shown in the figure, or combine certain components, or have a different arrangement of components.

[0142] In an exemplary embodiment, an analysis device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the following steps when executing the computer program: configuring driving condition parameters of a whole vehicle model HIL system so that the whole vehicle model HIL system simulates a real vehicle, generating a control signal according to the driving condition parameters, and sending the control signal to an electric drive system test bench; the control signal is used to instruct the electric drive system test bench to control the electric drive system to perform corresponding actions; obtaining operating data of the electric drive system through sensors; and evaluating performance indicators of the electric drive system based on the operating data to obtain energy flow test results.

[0143] In one embodiment, when the processor executes the computer program, the following steps are also implemented: determining the input power of the electric drive system based on the input current collected by the first current sensor; determining the output power of the electric drive system based on the output torque and output speed collected by the speed and torque sensor; and evaluating the energy efficiency of the electric drive system based on the input power and the output power.

[0144] In one embodiment, when the processor executes the computer program, the following steps are also implemented: determining the output power of the inverter based on the three-phase current collected by the second current sensor; calculating the electromagnetic power of the drive motor; and evaluating the energy flow state of the electric drive system based on the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor, and the output power of the electric drive system.

[0145] In one embodiment, when the processor executes the computer program, the following steps are also implemented: determining the heat dissipation power of the cooling system based on the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor; and evaluating the cooling performance index of the electric drive system based on the heat dissipation power.

[0146] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., but are not limited to this.

[0147] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0148] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for testing in-loop energy flow of an electric drive system, characterized in that: The method is applied to an in-the-loop energy flow test system, which includes a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system, and a main control system. The in-the-loop energy flow test system is also equipped with a sensor, and the electric drive system test bench is equipped with an electric drive system to be tested; the method includes: The driving condition parameters of the whole vehicle model HIL system are configured so that the whole vehicle model HIL system simulates a real vehicle, a control signal is generated according to the driving condition parameters, and the control signal is sent to the electric drive system; the control signal is used to instruct the electric drive system to perform a corresponding action; the high and low voltage power supply system supplies power to the electric drive system; the main control system is used to synchronize the status of the whole vehicle model HIL system with the electric drive system; Acquiring the operating data of the electric drive system through the sensor; Based on the operating data, the performance indicators of the electric drive system are evaluated to obtain energy flow test results.

2. The method according to claim 1, characterized in that The performance index includes energy efficiency; the sensor package includes a speed torque sensor and a first current sensor; the electric drive system to be tested includes a motor controller, a drive motor and a main reducer; the speed torque sensor is installed at the output end of the main reducer, and the first current sensor is installed at the input end of the motor controller; The step of evaluating the performance index of the electric drive system according to the operating data includes: Determining the input power of the electric drive system according to the input current collected by the first current sensor; Determining the output power of the electric drive system according to the output torque and output speed collected by the speed and torque sensor; The energy efficiency of the electric drive system is evaluated according to the input power and the output power.

3. The method according to claim 2, characterized in that The performance indicator also includes an energy flow state; the sensor also includes a second current sensor; the motor controller also includes an inverter; the second current sensor is installed at the three-phase output end of the inverter; The method further comprises: Determining the output power of the inverter according to the three-phase current collected by the second current sensor; Calculating the electromagnetic power of the driving motor; The energy flow state of the electric drive system is evaluated according to the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor, and the output power of the electric drive system.

4. The method according to claim 2, characterized in that The performance index also includes a cooling performance index; the electric drive system to be tested also includes a cooling system; the motor controller is used to adjust the working state of the cooling system according to the motor output state; the sensor also includes a temperature sensor, and the temperature sensor is used to detect the coolant inlet temperature and the coolant outlet temperature of the cooling system; The step of evaluating the performance index of the electric drive system according to the operating data includes: Determining the heat dissipation power of the cooling system according to the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor; According to the heat dissipation power, a cooling performance index of the electric drive system is evaluated.

5. An in-loop energy flow test system for an electric drive system, characterized in that: The system includes a vehicle model HIL system, an electric drive system test bench, a high and low voltage power supply system, a main control system and an analysis device. The system is also equipped with a sensor, and the electric drive system test bench is equipped with an electric drive system to be tested; The vehicle model HIL system is used to simulate a real vehicle, generate a control signal according to the driving condition parameters, and send the control signal to the electric drive system; The electric drive system is used to perform corresponding actions according to the control signal; The high and low voltage power supply system is used to supply power to the electric drive system; The main control system is used to synchronize the status of the vehicle model HIL system and the electric drive system; The sensor is used to collect operating data of the electric drive system and transmit the operating data to the analysis device through the main control system; The analysis device is used to evaluate the performance indicators of the electric drive system according to the operating data to obtain energy flow test results.

6. The system according to claim 5, characterized in that The performance index includes energy efficiency; the sensor package includes a speed torque sensor and a first current sensor; the electric drive system to be tested includes a motor controller, a drive motor and a main reducer; the speed torque sensor is installed at the output end of the main reducer, and the first current sensor is installed at the input end of the motor controller; The analysis device is also used to determine the input power of the electric drive system based on the input current collected by the first current sensor; determine the output power of the electric drive system based on the output torque and output speed collected by the speed and torque sensor; and evaluate the energy efficiency of the electric drive system based on the input power and the output power.

7. The system according to claim 6, characterized in that The performance indicator also includes an energy flow state; the sensor also includes a second current sensor; the motor controller also includes an inverter; the second current sensor is installed at the three-phase output end of the inverter; The analysis device is also used to determine the output power of the inverter based on the three-phase current collected by the second current sensor; calculate the electromagnetic power of the drive motor; and evaluate the energy flow state of the electric drive system based on the input power of the electric drive system, the output power of the inverter, the electromagnetic power of the drive motor and the output power of the electric drive system.

8. The system according to claim 6, characterized in that The performance index also includes a cooling performance index; the electric drive system to be tested also includes a cooling system; the motor controller is used to adjust the working state of the cooling system according to the motor output state; the sensor also includes a temperature sensor, and the temperature sensor is used to detect the coolant inlet temperature and the coolant outlet temperature of the cooling system; The analysis device is also used to determine the heat dissipation power of the cooling system according to the coolant inlet temperature and the coolant outlet temperature collected by the temperature sensor; and evaluate the cooling performance index of the electric drive system according to the heat dissipation power.

9. The system according to claim 5, characterized in that The high and low voltage power supply system includes high and low voltage load boxes and high and low voltage battery simulators; The high and low voltage load boxes are used to simulate the electrical load during the operation of the vehicle; The high and low voltage battery simulator is used to supply power to the high and low voltage load boxes; The high and low voltage load boxes are also used to supply power to the electric drive system based on the electrical load with the support of the high and low voltage battery simulators.

10. The system according to claim 5, characterized in that The whole vehicle model HIL system includes a vehicle model and a vehicle controller model; The vehicle model is used to simulate a real vehicle and generate a pedal demand according to the driving condition parameters; The vehicle controller model is used to calculate the torque demand of the drive motor according to the pedal demand and the vehicle state, and generate a control signal according to the torque demand.

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