Performance detection equipment for electronic power unit of dual-redundancy R-EPS steering system

Abstract

The invention provides a dual-redundancy R-EPS steering system electronic power unit performance detection device, and relates to the technical field of steering system testing. The control unit is in communication connection with the upper computer; the actuating mechanism comprises a programmable load motor, the control end of the actuating mechanism is connected with the control unit, and the output end of the actuating mechanism is connected with a motor output shaft of the tested electronic power unit; the sensing feedback module comprises a plurality of sensors used for collecting operation parameters of the tested electronic power unit, and each sensor is connected with the control unit; the fault simulation module is integrated in the control unit, and the output end of the fault simulation module is used for connecting a fault injection node of the tested electronic power unit; wherein the programmable load motor, the sensing feedback module and the fault simulation module form an integrated test system for performing dynamic load test and active fault injection test on the tested electronic power unit under the coordination of the control unit. High integration and automation of the detection process can be realized, and the test efficiency and consistency are improved.

Description

Technical Field

[0001] This invention belongs to the field of steering system testing technology, specifically relating to a performance testing device for a dual-redundant R-EPS steering system electronic power unit. Background Technology

[0002] In the field of automotive steering system technology, especially for dual-redundant R-EPS (electric power steering) systems used in advanced autonomous vehicles, the performance and reliability of the core electronic power unit (integrating the motor and ECU) directly determine the steering safety level of the entire vehicle. Therefore, comprehensive and rigorous specialized testing must be conducted on it before mass production.

[0003] Currently, the mainstream testing solution in the industry adopts a model of "multi-device step-by-step testing combined with manual verification". The specific process is usually as follows: people operate different independent devices in sequence to complete the initial electrical safety inspection, motor parameter testing, fault simulation and other stages. This decentralized testing method has technical defects: the testing process is fragmented, and the connection between each stage depends on manual labor, resulting in low overall testing efficiency. It cannot meet the requirements of mass production for cycle time (such as single-piece testing time ≤ 6 minutes), and the large number of manual interventions makes it difficult to ensure consistency and data traceability. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, a performance testing device for a dual-redundant R-EPS steering system electronic power unit is provided, comprising: Host computer; The control unit is communicatively connected to the host computer; An actuator, comprising a programmable load motor, wherein the control terminal of the programmable load motor is connected to the control unit, and its output terminal is used to connect to the motor output shaft of the electronic power unit under test; The sensing feedback module includes multiple sensors for collecting the operating parameters of the tested electronic power unit, and each sensor is connected to the control unit. The fault simulation module is integrated into the control unit, and its output is used to connect to the fault injection node of the tested electronic power unit. The programmable load motor, the sensing feedback module, and the fault simulation module, under the coordination of the control unit, constitute an integrated test system for performing dynamic load testing and active fault injection testing on the electronic power unit under test. The fault simulation module includes a signal simulation unit and a power fault injection unit; The signal simulation unit is configured to: inject simulated signals of sensor signal abnormality or communication bus abnormality into the electronic power unit under test; The power fault injection unit is configured to: inject short-circuit or voltage surge signals into the motor windings or ECU power supply circuit of the electronic power unit under test; The injection action of the fault simulation module and the monitoring action of the sensing feedback module are synchronously controlled by the control unit to verify the fault identification and redundancy switching response of the tested electronic power unit.

[0005] According to the technical solution provided in this application, the programmable load motor is a servo motor, and its output shaft is coaxially connected to the motor output shaft of the electronic power unit under test through a rigid coupling. It is used to switch between torque control mode and speed control mode under the control of the control unit to reproduce the dynamic load spectrum of vehicle steering.

[0006] According to the technical solution provided in this application, the sensing feedback module includes a torque and speed sensor, a current sensor, and a position sensor; The torque and speed sensor is connected in series with the motor output shaft of the electronic power unit under test, and is used to synchronously collect motor torque and speed parameters; The current sensor is connected in series in the motor power supply circuit of the electronic power unit under test, and is used to collect the winding current. The position sensor is set corresponding to the motor rotor of the electronic power unit under test and is used to detect the rotor position.

[0007] According to the technical solution provided in this application, a security protection module is also included, the security protection module comprising: A hardware emergency stop unit is connected in series in the power supply circuit of the programmable load motor and the electronic power unit under test; The software out-of-tolerance protection unit is integrated into the control unit and is used to compare the data collected by the sensing feedback module with the preset safety threshold in real time, and to trigger the programmable load motor to stop when the out-of-tolerance occurs. The security protection module provides redundant security protection for the dynamic load test and the active fault injection test.

[0008] According to the technical solution provided in this application, the sensing feedback module further includes: The insulation resistance detection unit has test probes that are used to connect the motor windings and ECU power supply terminals of the electronic power unit under test, and automatically detect the insulation resistance to ground based on the balanced bridge method. The ECU signal acquisition unit has a pin connector for connecting the control signal output terminal and the fault feedback terminal of the ECU in the tested electronic power unit, and is used to acquire the ECU's PWM control signal and fault status signal in real time.

[0009] According to the technical solution provided in this application, it further includes a test process management module that is communicatively connected to the control unit; the test process management module is configured to: Send a serialization test command to the control unit; Receive and integrate detection data from the sensing feedback module; According to preset logic, the fault simulation module is triggered to inject a fault at a specific node in the test sequence; The serialized test instructions drive the device to complete electrical safety verification, sensor calibration, dynamic performance testing, and redundancy safety verification.

[0010] According to the technical solution provided in this application, the fault simulation module further includes a communication anomaly simulation unit, which is configured to: Under the coordination of the control unit, a simulated anomaly is injected into the CAN bus connected to the electronic power unit under test. The simulated anomaly includes at least one of communication delay, data packet loss, and bus collision. The control unit synchronously monitors the operating status and redundancy switching response of the tested electronic power unit under simulated abnormality through the sensing feedback module.

[0011] According to the technical solution provided in this application, the pre-set serialized test instructions in the test process management module drive the device to automatically execute the following detection steps in sequence: Perform preliminary checks to verify the connection status of each module of the equipment and the electronic power unit under test; Perform basic performance pre-tests on the electronic power unit, including insulation resistance, motor winding parameters, and ECU power supply stability testing; Perform MPS calibration, and read and verify position sensor data at a preset speed; Perform zero-position calibration, control the tested motor to learn itself and calculate and write the zero-position deviation; Perform no-load and load dynamic performance tests and collect three-dimensional dynamic parameters of speed, torque and current. Perform fault injection and redundancy switching verification, inject at least one type of fault and verify switching latency and performance retention; Perform communication and system flag verification; The output includes a test report containing all process data and diagnostic results.

[0012] According to the technical solution provided in this application, the control unit is configured to: When driving the actuator to perform the dynamic load test, a closed-loop control strategy combining incremental PID algorithm and torque feedforward compensation technology is adopted. The control unit generates a feedforward compensation signal based on the target load torque change rate and simultaneously performs PID closed-loop correction based on the real-time torque feedback signal collected by the sensing feedback module.

[0013] Compared with existing technologies, the advantages of this application are: it achieves a high degree of integration and automation of the testing process, greatly improving testing efficiency and consistency. By integrating the host computer, control unit, actuator (including programmable load motor), sensor feedback module, and fault simulation module into one unit, a complete closed-loop testing system is formed under the coordination of the control unit. This system can automatically and continuously execute the entire process from electrical safety inspection and performance testing to fault injection verification, replacing the traditional mode of step-by-step operation of multiple devices and manual intervention. This not only significantly shortens the testing time of a single product to meet mass production cycle time, but also avoids human operation errors through automated scripts, ensuring high consistency and repeatability of the testing process and results, while realizing automatic data acquisition and full traceability of testing data. Attached Figure Description

[0014] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 A schematic diagram of the structure of the performance testing equipment for the dual-redundant R-EPS steering system electronic power unit provided in this application; The text labels in the image represent: 1. Host computer; 2. Control unit; 3. Fault simulation module; 4. Actuator; 5. Sensor feedback module. Detailed Implementation

[0015] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0016] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0017] As mentioned in the background section, this application proposes a performance testing device for a dual-redundant R-EPS steering system electronic power unit, such as... Figure 1 As shown, it includes: Host computer 1; Control unit 2 is communicatively connected to the host computer 1; The actuator 4 includes a programmable load motor, the control terminal of which is connected to the control unit 2, and its output terminal is used to connect to the motor output shaft of the electronic power unit under test. The sensing feedback module 5 includes multiple sensors for collecting the operating parameters of the tested electronic power unit, and each sensor is connected to the control unit 2. The fault simulation module 3 is integrated into the control unit 2, and its output is used to connect to the fault injection node of the tested electronic power unit. The programmable load motor, the sensing feedback module 5, and the fault simulation module 3, under the coordination of the control unit 2, constitute an integrated test system for performing dynamic load testing and active fault injection testing on the electronic power unit under test.

[0018] Specifically, the host computer 1 uses an industrial control computer (model: IPC-610L) equipped with customized testing software developed based on LabVIEW (response latency ≤50ms), and has 7 built-in test automation scripts. Hardware interfaces include an RJ45 Ethernet interface (communication protocol: TCP / IP), a VGA interface (for connecting to a monitor), and a USB interface (for connecting to a printer). Its core functions include parameter configuration, data acquisition, real-time curve generation, anomaly alarms, and report output.

[0019] Control Unit 2: Employs an ARM Cortex-M7 processor (model: STM32H743VI, 400MHz), integrating a CAN module (model: TJA1050, supporting UDS protocol, 500kbps baud rate, communication latency ≤10ms), a 16-bit PWM driver module (model: IR2110), and a fault simulation module 3 (model: ADG1419). It establishes a communication connection with the host computer 1 via an RJ45 Ethernet interface, receiving commands from the host computer 1 and feeding back detection data.

[0020] Actuator 4 includes a programmable load motor (servo load motor, model: MS1H1-10B30CB-A331Z, rated torque 5Nm, peak torque 10Nm, speed 0-3000RPM, control accuracy ±1RPM), a rigid coupling (model: LK45, material: 45# steel), and a motor mounting bracket (material: POM, fixed to the test bench with 4 M8 bolts). The control terminal of the programmable load motor is connected to the control unit 2 through the output terminal (pins PA8-PA11) of the PWM drive module. Its output shaft is coaxially connected to the output shaft of the motor of the electronic power unit under test through the rigid coupling (using key connection + lock nut for fixation, coaxiality error ≤0.02mm).

[0021] Sensing feedback module 5: This is a full-dimensional sensing feedback module 5, containing 5 sub-modules. Each sensor is connected to the control unit 2 through a corresponding interface. Torque and speed sensor (range 0-10Nm / 0-6000RPM, accuracy ±0.1% FS): connected in series between the motor under test and the coupling, connected to the ADC interface of the control unit 2 via a shielded cable, with a sampling frequency of 1kHz, used to collect motor speed and torque parameters; Current sensor (model: ACS712-50A, range 0-50A, accuracy ±0.2% FS): connected in series in the power supply circuit of the motor winding under test, and the output terminal is connected to the ADC interface of the control unit to monitor the stability of the winding current. Position sensor (model: E6B2-CWZ6C, accuracy ±0.01°): It is fixed to the end cover of the motor under test by a bracket. The detection head is coaxially attached to the motor rotor shaft. The output end is connected to the encoder interface of control unit 2 for zero position calibration. Insulation resistance testing module (model: CH2671, output voltage 12V / 24V adaptive): The test probe is connected to the winding of the motor under test and the power supply terminal of the ECU. The signal control line is connected to the 2GPIO interface of the control unit. The insulation performance is tested by the balanced bridge method. ECU signal acquisition module (model: PCI-6221): Connects to the PWM output and fault feedback terminals of the ECU under test via pin connectors. The data transmission line connects to control unit 2. The sampling frequency is 1kHz, acquiring ECU control signals and fault feedback signals. All sensor modules use shielded cables for connection, and the grounding terminals are uniformly connected to the test bench grounding busbar (grounding resistance ≤4Ω) to avoid electromagnetic interference.

[0022] Fault simulation module 3: Integrated into control unit 2 (model: ADG1419), its output is connected to the fault injection node of the tested electronic power unit (including sensor signal interface, motor winding power supply circuit, ECU power supply interface, CAN bus interface) through signal channel switching, and is used to inject simulated signals such as sensor fault, actuator fault, ECU fault and communication abnormality.

[0023] Integrated Test System Working Logic: Control Unit 2 receives test commands from Host Computer 1 via RJ45 Ethernet interface, coordinating the collaborative work of programmable load motor, sensor feedback module 5, and fault simulation module 3. During dynamic load testing, the control unit 2 outputs a PWM signal to drive the programmable load motor to switch between speed control mode and torque control mode, thus reproducing the dynamic load characteristics of vehicle steering. The sensor feedback module 5 synchronously collects the operating parameters of the tested electronic power unit, such as speed, torque, current, rotor position, and ECU control signal, and uploads them to the control unit 2 for processing before feeding them back to the host computer 1. During active fault injection testing, control unit 2 controls fault simulation module 3 to inject various fault signals into the electronic power unit under test at preset test nodes. Sensing feedback module 5 monitors the operating status and redundancy switching response after fault injection in real time. Control unit 2 records data such as fault identification delay and switching delay to ensure a closed-loop test process.

[0024] In a preferred embodiment, the programmable load motor is a servo motor, and its output shaft is coaxially connected to the motor output shaft of the electronic power unit under test via a rigid coupling. This allows the motor to switch between torque control mode and speed control mode under the control of the control unit 2, so as to reproduce the dynamic load spectrum of vehicle steering.

[0025] Specifically, the programmable load motor adopts a servo load motor (model: MS1H1-10B30CB-A331Z), with a rated torque of 5Nm, a peak torque of 10Nm, a speed adjustment range of 0-3000RPM, and a control accuracy of ±1RPM. It supports dynamic switching between speed control mode and torque control mode. Its driver (model: MEDL-TB3BF) receives mode switching instructions and parameter adjustment signals from the control unit 2 through PWM signals. Mechanical connection: The output shaft of the servo load motor is coaxially connected to the output shaft of the motor of the electronic power unit under test through a rigid coupling (model: LK45, material: 45 steel). Double fixation is adopted by key connection and lock nut to ensure coaxiality error ≤0.02mm, avoiding test data distortion caused by mechanical deviation. The torque and speed sensor (range 0-10Nm / 0-6000RPM, accuracy ±0.1% FS) is connected in series between the coupling and the motor under test. Both ends are connected to the coupling and the motor under test respectively through flanges (M6 bolts) to realize synchronous acquisition of speed and torque under load.

[0026] Dynamic load spectrum reproduction implementation: Based on the dynamic load curve command issued by the host computer 1, control unit 2 uses an incremental PID control algorithm (speed control mode) or a feedforward-feedback composite algorithm (torque control mode) to drive the servo load motor to reproduce the dynamic load spectrum of vehicle steering. Speed ​​Cyclic Load: Output PWM signal according to 10-second curve (0→+3000→0→-3000→0RPM), and realize smooth speed transition through PID closed-loop control. The speed fluctuation is ≤±1RPM, simulating the speed change process from stationary turning to high-speed driving. Torque load simulation: Switch to torque control mode, adjust the load to 3Nm (corresponding to the vehicle steering limit condition) through feedforward-feedback composite algorithm (feedforward coefficient 0.8), maintain load stability, and simultaneously collect the dynamic response parameters of the tested electronic power unit; Mode switching logic: Control unit 2 automatically switches between speed / torque modes according to the test process instructions, with a switching response time of ≤200ms, ensuring the continuity and realism of the load simulation.

[0027] In a preferred embodiment, the sensing feedback module 5 includes a torque and speed sensor, a current sensor, and a position sensor; The torque and speed sensor is connected in series with the motor output shaft of the electronic power unit under test, and is used to synchronously collect motor torque and speed parameters; The current sensor is connected in series in the motor power supply circuit of the electronic power unit under test, and is used to collect the winding current. The position sensor is set corresponding to the motor rotor of the electronic power unit under test and is used to detect the rotor position.

[0028] Specifically, the torque and speed sensor configuration and function implementation are as follows: Selection parameters: A torque and speed sensor with a range of 0-10Nm / 0-6000RPM, an accuracy of ±0.1% FS, a sampling frequency of 1kHz, and an anti-electromagnetic interference design is adopted. It is connected to the ADC interface of control unit 2 via a shielded cable. Installation position: It is connected in series between the output shaft of the motor of the tested electronic power unit and the rigid coupling. Both ends are mechanically fixed by flanges (M6 bolts), ensuring coaxiality with the output shaft of the tested motor and the output shaft of the load motor (coaxiality error ≤0.02mm). It collects the motor speed and torque parameters under load conditions in real time and synchronously uploads them to control unit 2 to provide feedback signals for closed-loop control. Functions: In no-load testing, it collects motor no-load speed fluctuation data (≤±1RPM); in load testing, it synchronously collects three-dimensional dynamic data of speed-torque-current, verifying that torque fluctuation is ≤0.2 times the average torque; in redundancy switching testing, it detects the torque mutation value during the switching process (≤0.3Nm).

[0029] Current Sensor Configuration and Functionality: Selection Parameters: Model ACS712-50A, Range 0-50A, Accuracy ±0.2%FS, with overcurrent protection signal output function, connected to the ADC interface of Control Unit 2 via a shielded cable. Installation Method: Connected in series in the power supply circuit of the motor winding of the tested electronic power unit, ensuring accurate current sampling and avoiding measurement errors caused by current shunting. Function: Monitors the current stability of the motor winding, acquiring no-load current (≤2A) in no-load tests, acquiring dynamic current change data in load tests, and monitoring overcurrent signals (≥50A) in fault injection tests (such as winding short-circuit faults), providing data support for motor winding parameter calculation (such as phase resistance deviation ≤2%) and fault identification.

[0030] Position sensor configuration and function implementation: Selection parameters: Model E6B2-CWZ6C, accuracy ±0.01°, output signal is incremental encoder signal, connected to the encoder interface of control unit 2 via shielded cable. Installation method: Fixed to the motor end cover of the tested electronic power unit using a custom bracket, the detection head is coaxially fitted with the motor rotor shaft to ensure no relative offset of the detection head when the rotor rotates, sampling interval 10μs to ensure real-time and accurate position detection. Function: During zero-position calibration, the position data of the motor rotor is collected in real time, uploaded to control unit 2, and the zero-position deviation is calculated using the least squares method to ensure that the zero-position calibration error is ≤0.05°; during redundancy switching tests, the rotor position change is monitored to verify the continuity of the steering angle during switching.

[0031] In a preferred embodiment, the fault simulation module 3 includes a signal simulation unit and a power fault injection unit; The signal simulation unit is configured to: inject simulated signals of sensor signal abnormality or communication bus abnormality into the electronic power unit under test; The power fault injection unit is configured to: inject short-circuit or voltage surge signals into the motor windings or ECU power supply circuit of the electronic power unit under test; The injection action of the fault simulation module 3 and the monitoring action of the sensing feedback module 5 are synchronously controlled by the control unit 2 to verify the fault identification and redundancy switching response of the tested electronic power unit.

[0032] Specifically, the composition and functional division of fault simulation module 3: Signal simulation unit: Integrated into fault simulation module 3 (model: ADG1419), it realizes analog signal output through signal channel switching, and connects to the sensor signal interface (such as MPS sensor interface) and CAN bus interface of the electronic power unit under test. Sensor signal anomaly simulation: simulates the loss of MPS signal output or the deviation of MPS signal by ±5° to simulate sensor failure or signal distortion fault; Communication bus anomaly simulation: The delay signal (0-100ms) is generated by the timer of control unit 2, the data packet loss (0-5%) is simulated by the random number algorithm, and the bus collision is simulated by the signal collision generator to verify the anti-interference capability of CAN bus communication.

[0033] Power fault injection unit: This unit is linked to the motor winding power supply circuit and ECU power supply interface of the tested electronic power unit via the power module and fault simulation module 3. Motor winding fault injection: Output short-circuit signal to motor winding to simulate a partial short-circuit fault in the winding and trigger an overcurrent signal (≥50A). ECU power supply fault injection: Output power supply voltage sudden change signal (12V→5V sudden change) and power supply interruption signal to simulate ECU power supply abnormal fault; Power module failure simulation: Cut off or disrupt the PWM drive signal to simulate a power module failure.

[0034] Synchronization control logic and verification process: Control unit 2 implements synchronous control of fault injection and monitoring based on the UDS protocol (Unified Diagnostic Service Protocol). The specific process is as follows: Control unit 2 sends a fault injection command (such as a sensor signal loss command, ID: 0x7DF, data segments 0x03 0x2E 0x30 0x01) to fault simulation module 3 via a CAN module (model: TJA1050, supporting UDS protocol); After receiving the instruction, the fault simulation module 3 injects the target fault signal into the electronic power unit under test at a preset time (synchronized with the test process node); The sensor feedback module 5 (torque and speed sensor, current sensor, ECU signal acquisition module, etc.) synchronously collects the operating parameters after fault injection (such as fault identification delay, torque change, redundancy switching action) and uploads them to the control unit 2 through the ADC interface or encoder interface. Control unit 2 sends a read command (ID: 0x7DF, data segment 0x02 0x22 0x20 0x02) via UDS protocol to read the diagnostic fault codes (DTCs) and redundancy switching status bits of the tested electronic power unit and verify the accuracy of fault identification. Control unit 2 compares the consistency of fault injection type and diagnostic code, redundancy switching delay (≤50ms), torque fluctuation after switching (≤0.2 times average torque), and assist performance retention rate (≥80% rated assist), generates verification results, and feeds them back to host computer 1.

[0035] Verification indicators and judgment criteria: Fault identification delay ≤20ms; Redundancy switching delay ≤50ms; The torque surge during the switching process is ≤0.3Nm; After switching, the single-channel motor assist performance is ≥80% of the rated assist (≥4Nm); No fault propagation phenomenon (e.g., a single sensor failure does not affect the normal operation of other modules); The fault codes correspond one-to-one with the fault types, and can be read and cleared using the UDS protocol.

[0036] In a preferred embodiment, a security protection module is further included, the security protection module comprising: A hardware emergency stop unit is connected in series in the power supply circuit of the programmable load motor and the electronic power unit under test; The software out-of-tolerance protection unit, integrated into the control unit 2, is used to compare the data collected by the sensing feedback module 5 with the preset safety threshold in real time, and to trigger the programmable load motor to stop when an out-of-tolerance condition is exceeded. The security protection module provides redundant security protection for the dynamic load test and the active fault injection test.

[0037] Specifically, the security protection module consists of the following components and hardware configuration: Hardware emergency stop unit: Selection: The normally closed button (model: LA38-11ZS) is used, which has an anti-accidental touch design. After pressing, it needs to be rotated clockwise to reset, ensuring operational safety. Connection method: Connected in series with the 24V main power supply circuit of the programmable load motor (model: MS1H1-10B30CB-A331Z) and the electronic power unit under test, forming a series protection circuit with the power switch and relay; Working logic: When the emergency stop button is pressed, the circuit is immediately disconnected, cutting off the power supply to the programmable load motor and the electronic power unit under test, stopping all mechanical movement and electrical testing. The response time is ≤10ms, which is suitable for rapid shutdown in emergency faults or dangerous scenarios.

[0038] Software out-of-tolerance protection unit: Integration Location: The software out-of-tolerance protection unit is integrated into the built-in program of the core control unit 2 (model: STM32H743VI), and is linked in real time with the data acquisition channel of the sensing feedback module 5; Threshold settings: The preset safety thresholds include the speed threshold (3000±50RPM) and the torque threshold (5Nm). At the same time, it supports flexible adjustment of the threshold range according to the parameter requirements of different models of dual redundant R-EPS electronic power units through the host computer software (developed based on LabVIEW). Working logic: The core control unit 2 compares the speed, torque and other data uploaded by the sensor feedback module 5 with the preset safety threshold in real time. When the parameter exceeds the tolerance, it immediately outputs a stop signal with 0% PWM duty cycle, triggers the relay to cut off the power output circuit, and sends an over-tolerance alarm signal (data format: 0x02 0x01 0x01) to the host computer 1, and records the over-tolerance parameters, timestamp and other fault information.

[0039] Redundant security protection logic: The security protection module provides dual redundancy protection for dynamic load testing and active fault injection testing: Hardware level: The hardware emergency stop unit is independent of the software control system. Even if the core control unit 2 or the software fails, the power supply can still be cut off by physical operation to prevent the danger from escalating. All power circuits are equipped with dual-circuit fuse protection (rated current 20A) to prevent overcurrent from causing line burnout or equipment damage. At the software level: In addition to over-tolerance protection, the core control unit 2 has built-in dual-channel MPS and communication cross-verification logic. When the deviation between the MPS data collected by the position sensor and the CAN bus communication data is ≥0.1°, it is judged as abnormal and the shutdown process is immediately triggered. During the fault injection test, if the risk of fault propagation is detected (such as multiple modules reporting faults at the same time), the software automatically starts hierarchical protection, first cutting off the power supply to the faulty module, and then evaluating whether to terminate the overall test. Collaborative protection: Hardware emergency stop and software over-tolerance protection can be triggered independently or in tandem. When the software detects an over-tolerance, if the system is not stopped within 100ms, the hardware emergency stop circuit will be automatically triggered to ensure the safety of personnel, equipment and the tested electronic power unit during the test.

[0040] In a preferred embodiment, the sensing feedback module 5 further includes: The insulation resistance detection unit has test probes that are used to connect the motor windings and ECU power supply terminals of the electronic power unit under test, and automatically detect the insulation resistance to ground based on the balanced bridge method. The ECU signal acquisition unit has a pin connector for connecting the control signal output terminal and the fault feedback terminal of the ECU in the tested electronic power unit, and is used to acquire the ECU's PWM control signal and fault status signal in real time.

[0041] Specifically, the configuration and function implementation of the insulation resistance detection unit are as follows: Selection parameters: The insulation resistance detection module (model: CH2671) is adopted, the output voltage supports 12V / 24V adaptive adjustment, it is matched with the low voltage working scenario of the dual redundant R-EPS electronic power unit in the vehicle, the detection range is 0-1000MΩ, the detection accuracy is ±5%, and it has overvoltage protection function (maximum output voltage does not exceed 30V). Connection method: Connect the motor winding and ECU power supply terminals under test through a customized test probe (with anti-misinsertion design, only compatible with the winding terminals and ECU power supply terminals of the tested electronic power unit). The signal control line is connected to the core control unit 2 (model: STM32H743VI) through the GPIO interface. The grounding terminal of the test module is connected to the grounding busbar of the test bench (grounding resistance ≤4Ω) to avoid grounding interference. Detection principle and process: The core control unit 2 sends a start command (GPIO output high level), and the insulation resistance detection module automatically switches to output 12V or 24V test voltage according to the power supply type of the electronic power unit under test; The balanced bridge method is used to collect the insulation resistance values ​​of the winding to ground and the ECU power supply circuit to ground through a high impedance sampling module. The analog signals are converted into digital signals and then uploaded to the core control unit 2. The core control unit 2 compares the detection data with the judgment threshold (≥100MΩ). If the threshold is met, it proceeds to the next test stage. If the threshold is not met, it outputs fault code 0x05 (insulation fault), triggers an audible and visual alarm (model: LTE-1101), and terminates the test. At the same time, it records the specific value of the insulation resistance and the detection location.

[0042] ECU signal acquisition unit configuration and function implementation: Selection parameters: ECU signal acquisition module (model: PCI-6221) is used, with a sampling frequency of 1kHz, supporting synchronous acquisition of PWM signals, digital signals, and analog signals, input voltage range of 0-30V, and sampling accuracy of ±0.1% FS; Connection method: Connect the PWM control signal output terminal and fault feedback terminal of the ECU in the tested electronic power unit through pin connectors (matched one by one with the signal interface of the ECU under test, with foolproof design). The data transmission line is connected to the core control unit 2 through the PCI interface and uses shielded cable to reduce electromagnetic interference. Content and functions to be collected: The PWM control signal output by the ECU is acquired in real time, including parameters such as duty cycle, frequency, and phase, to analyze the ECU's control logic and response speed, and to verify the stability of the PWM signal under dynamic load (duty cycle fluctuation ≤ ±1%). Collect fault status signals (digital quantities) from the ECU, including fault trigger flags and fault type codes, and synchronize them with the fault injection test to verify the accuracy of the ECU in identifying various faults. Data on ECU power supply voltage fluctuations are collected. Within the power supply fluctuation range of 12V±1V and 24V±2V, the voltage ripple is monitored to be ≤50mV to ensure the stability of the ECU power supply and provide data support for the basic performance evaluation of the electronic power unit.

[0043] In a preferred embodiment, a test process management module communicatively connected to the control unit 2 is further included; the test process management module is configured to: Send a serialization test command to the control unit 2; Receive and integrate detection data from the sensing feedback module 5; According to the preset logic, the fault simulation module 3 is triggered to inject a fault at a specific node in the test sequence; The serialized test instructions drive the device to complete electrical safety verification, sensor calibration, dynamic performance testing, and redundancy safety verification.

[0044] Furthermore, the pre-set serialized test instructions in the test process management module drive the device to automatically execute the following detection steps sequentially: Perform preliminary checks to verify the connection status of each module of the equipment and the electronic power unit under test; Perform basic performance pre-tests on the electronic power unit, including insulation resistance, motor winding parameters, and ECU power supply stability testing; Perform MPS calibration, and read and verify position sensor data at a preset speed; Perform zero-position calibration, control the tested motor to learn itself and calculate and write the zero-position deviation; Perform no-load and load dynamic performance tests and collect three-dimensional dynamic parameters of speed, torque and current. Perform fault injection and redundancy switching verification, inject at least one type of fault and verify switching latency and performance retention; Perform communication and system flag verification; The output includes a test report containing all process data and diagnostic results.

[0045] Specifically, the configuration and connection relationships of the test process management module are as follows: Hardware carrier: The test process management module is integrated into the customized test software (developed based on LabVIEW, with a response latency of ≤50ms) of the host computer 1 (model: IPC-610L). It establishes a communication connection with the core control unit 2 (model: STM32H743VI) through the RJ45 Ethernet interface (communication protocol: TCP / IP), with a data transmission rate of ≥100Mbps to ensure the real-time performance of command issuance and data upload. Software architecture: Built-in serialized test instruction library, data integration algorithm, and fault injection triggering logic module, supporting custom editing of test process (such as adding test steps, adjusting test order, and modifying parameter thresholds), adapting to the testing needs of different models of dual redundant R-EPS electronic power units.

[0046] Core functionality implementation method: Serialization test command issuance: The test process management module pre-sets serialization test commands for 8 stages, which are sent to the core control unit 2 sequentially according to the preset logic. The command data format is uniformly hexadecimal, including fields such as command type, parameter value, and checksum, as follows: Pre-test command (0x01 0x00 0x01): Triggers the initialization of each module of the device and the connection test of the electronic power unit under test; Basic performance pre-test instructions (0x01 0x02 0x01): Initiate insulation resistance, motor parameters, and ECU power supply stability tests; MPS calibration command (0x01 0x03 0x01): Set the calibration speed to 400±5RPM and trigger UDS protocol reading and message verification; Zero-position calibration command (0x01 0x04 0x01): Triggers the forward and reverse self-learning and zero-position deviation calculation of the tested motor; Dynamic performance test command (0x01 0x05 0x01): Switch the load motor mode and start the no-load / load test; Fault injection and redundancy verification instructions (0x01 0x06 0x01): Set the fault type and injection timing, and start redundancy switching verification; Communication and flag check instructions (0x01 0x07 0x01): Send UDS test instructions and flag read instructions; Output command (0x01 0x08 0x01): Triggers full-process data packaging, uploading, and report generation.

[0047] Data reception and integration: The core control unit 2 packages the detection data such as speed, torque, current, insulation resistance, and ECU signals collected by the sensor feedback module 5 into JSON format and uploads it to the test process management module every 10ms. The module uses a built-in data integration algorithm to associate and integrate the scattered parameter data, generate multi-dimensional real-time curves such as speed-time, torque-current, and voltage-fluctuation, and establish a data index (associated with motor serial number, test time, and test personnel) to support traceability.

[0048] Fault Injection Trigger Control: The test process management module triggers the fault simulation module 3's action in the "Fault Injection and Redundancy Switching Verification" stage (stage 6) according to the preset test sequence. Specific logic: The module sends fault injection parameters (fault type code, injection duration, triggering conditions) to the core control unit 2. After the core control unit 2 parses the parameters, it controls the fault simulation module 3 (model: ADG1419) to switch the signal channel and inject the target fault; The module synchronously receives monitoring data from the sensor feedback module 5, and judges the fault identification delay and redundancy switching effect in real time. If the preset indicators are not met (such as switching delay > 50ms), an alarm is immediately triggered and fault data is recorded.

[0049] Serialization testing process: The test process management module sends serialized instructions to drive the device to automatically execute the following testing steps in sequence. The steps are seamlessly connected, and the testing time for a single device is ≤6 minutes: Pre-test: Verify the power supply to the device module and the connection status of the unit under test; Basic performance pre-test: Complete insulation, motor parameters, and ECU power supply tests; MPS calibration: Enables location data reading and verification with a detection rate of ≥99.5%; Zero-point calibration: Complete the calculation and writing of the zero-point deviation, with an error ≤ 0.05°; Dynamic performance testing: Acquiring three-dimensional dynamic parameters under no-load and loaded conditions; Fault Injection and Redundancy Verification: Inject three typical faults to verify the effectiveness of redundancy switching; Communication and flag verification: Completes message consistency, fault code, and communication anomaly verification; Output results: Generate a detection report containing curves and fault logs, and store and trace the results.

[0050] Specifically, the serialization test instruction triggering logic: The test process management module (integrated into the LabVIEW software on the host computer 1) has a pre-set serialized test instruction library. It sends instructions sequentially to the core control unit 2 (model: STM32H743VI) via the RJ45 Ethernet interface (TCP / IP protocol). The instructions include the stage code, parameter configuration, and check bit field. After receiving the instructions, the core control unit 2 drives the modules to work together through the built-in state machine trigger mechanism. The steps are seamlessly connected, and the total test time for a single unit is ≤6 minutes.

[0051] Specific implementation process of each testing step: Step 1: Preliminary checks: Triggering condition: Host computer 1 sends an initialization command (data format: 0x01 0x00 0x01); Actions performed: ① The core control unit 2 sends a connection detection signal (ID: 0x749, data segment 0x00) to the tested electronic power unit via the CAN module (model: TJA1050); ② The power supply voltage of each sensor is detected via the GPIO interface (standard value 5V±0.1V). Judgment Logic: When the tested electronic power unit returns a "Ready" signal (ID: 0x749, data segment 0x01) and the sensor power supply is normal, the core control unit 2 sends a "Startable" signal (data format: 0x01 0x000x02) to the host computer 1 and proceeds to the next stage; otherwise, the audible and visual alarm module (model: LTE-1101) is triggered, outputting fault codes (sensor fault code 0x01, connection fault code 0x02), and the process is terminated.

[0052] Step 2: Pre-testing of basic performance of the electronic power unit: Insulation resistance detection: The core control unit 2 starts the insulation resistance detection module (model: CH2671) by outputting a high level through GPIO, outputting a 12V / 24V adaptive voltage, and collecting the insulation resistance value of the winding and ECU power supply circuit based on the balanced bridge method. The judgment threshold is ≥100MΩ, and the data is uploaded through the ADC interface. Motor parameter detection: The core control unit 2 outputs a PWM signal with a duty cycle of 5% to drive the motor under test to rotate under no-load. The current sensor (model: ACS712-50A) collects the no-load current (≤2A), and the torque and speed sensor collects the back EMF data to calculate the winding phase resistance deviation (≤2%) and the back EMF waveform distortion rate (≤5%). ECU power supply test: The power supply voltage is collected through the ECU signal acquisition module (model: PCI-6221), and the voltage stability (ripple ≤50mV) under fluctuations of 12V±1V and 24V±2V is tested. Abnormal handling: When any parameter fails to meet the standard, the core control unit 2 sends a stop command with PWM duty cycle of 0%, uploads fault data to the host computer 1, and terminates the process with an alarm.

[0053] Step 3: MPS Calibration: Speed ​​control: The core control unit 2 drives the servo load motor to maintain a stable speed of 400±5RPM through an incremental PID algorithm, and maintains the steady state for 100ms. Data reading and verification: Send a UDS read command (ID: 0x7DF, data segment 0x02 0x220x10 0x01) via CAN module to read MPS position data; verify the number of bytes (8 bytes), CRC-8 check bits and status bits (0x01 for normal) of the feedback message (ID: 0x749). Result processing: If the verification passes, store the MPS calibration data; otherwise, output fault code 0x03 and trigger an alarm to terminate the process.

[0054] Step 4: Zero-point calibration: Mode switching: Core control unit 2 controls the servo load motor to stop and switch to no-load mode; Self-learning and data acquisition: The DID command (ID: 0x7DF, data segment 0x03 0x2E 0x200x01) is sent through the CAN module to trigger the forward and reverse self-learning of the tested motor. The position sensor (model: E6B2-CWZ6C) collects rotor position data at a sampling interval of 10μs and uploads it to the core control unit 2. Calibration calculation and verification: The core control unit 2 calculates the zero-position deviation using the least squares method and writes the calibration data into the NvM (non-volatile memory) of the motor under test; when the "calibration completed" bit (ID: 0x749, 3rd byte of data segment 0x01) is read and the zero-position error is ≤0.05°, proceed to the next stage; otherwise, repeat the calibration twice. If it still fails to meet the standard, an alarm will be triggered.

[0055] Step 5: Dynamic performance test under no-load and load conditions: No-load test: The core control unit 2 outputs a PWM signal (duty cycle 0-10%-0-(-10%)-0) according to a 10-second curve. The speed transition is achieved through PID closed-loop control. The torque and speed sensor collects speed fluctuation data (≤±1RPM) and uploads it to the host computer 1 in real time. Load test: Send a command to switch the servo load motor to torque mode, and adjust the load to 3Nm through a feedforward-feedback composite algorithm (feedforward coefficient 0.8, feedback PID parameters are the same as in step 3). Simultaneously collect three-dimensional data of speed-torque-current (sampling frequency 1kHz), and verify that the torque fluctuation is ≤0.2 times the average torque. Process progress: After the test is completed, the core control unit 2 sends a "test normal" signal to the host computer 1 (data format: 0x01 0x05 0x01).

[0056] Step 6: Fault Injection and Redundancy Switching Verification: Fault injection: The core control unit 2 injects three types of faults sequentially through the fault simulation module 3 (model: ADG1419): ① Sensor fault (MPS signal loss / deviation ±5°); ② Actuator fault (motor winding short circuit, current ≥50A); ③ ECU fault (power supply 12V→5V sudden change, communication interruption). Redundancy verification: Real-time monitoring of fault identification delay (≤20ms) via CAN module, and detection of redundancy switching delay (≤50ms) and torque fluctuation after takeover (≤0.2 times average torque) via torque and speed sensors. Judgment criteria: If the assist performance is ≥80% of the rated assist (≥4Nm) in safe working mode, the redundancy switching is deemed effective; otherwise, output fault code 0x04 and record the fault data.

[0057] Step 7: Communication and System Flag Verification: Command transmission: Core control unit 2 sends UDS test command (ID: 0x7DF, data segment 0x02 0x3E 0x00) and flag bit read command (ID: 0x7DF, data segment 0x02 0x22 0x20 0x02). Verification content: ① Feedback message consistency (deviation from preset message ≤ 1 bit); ② No DTC fault code (4th byte of data segment 0x00); ③ Flag_Redundancy_Test_Finish=0x01; ④ Simulate communication delay (0-100ms) and packet loss (0-5%) through fault simulation module 3 to verify that the tested electronic power unit can work normally or safely degrade. Process Implementation: After successful verification, the process proceeds to the result output stage.

[0058] Step 8: Output the results: Data Upload: The core control unit 2 packages the entire process detection data (including parameters and fault logs) in JSON format and uploads it to the host computer 1; Report generation: The host computer software generates a test report containing real-time curves and fault diagnosis logs, marking non-conforming items and corresponding fault codes and fault locations; Data storage and output: The report is printed out and simultaneously stored on the local hard drive (path: D:\Detection Data\) and the production line MES system. The data retention period is ≥3 years, and it supports accurate traceability by motor serial number.

[0059] In a preferred embodiment, the fault simulation module 3 further includes a communication anomaly simulation unit, configured to: Under the coordination of the control unit 2, a simulated anomaly is injected into the CAN bus connected to the electronic power unit under test. The simulated anomaly includes at least one of communication delay, data packet loss, and bus collision. The control unit 2 synchronously monitors the working status and redundancy switching response of the tested electronic power unit under simulated abnormality through the sensing feedback module 5.

[0060] Specifically, the configuration and integration method of the communication anomaly simulation unit: Hardware integration: The communication anomaly simulation unit is integrated into the CAN module (model: TJA1050) of the core control unit 2, and works in conjunction with the fault simulation module 3 (model: ADG1419). It is connected to the CAN communication interface of the electronic power unit under test through the CAN bus interface, supports UDS protocol, baud rate of 500kbps, and communication delay ≤10ms. Software support: The core control unit 2 has a built-in communication anomaly simulation algorithm, including a delay signal generation module, a random packet loss algorithm module, and a bus conflict simulation module. Anomaly parameters (delay time, packet loss rate, and conflict frequency) can be configured through the test process management module of the host computer 1.

[0061] Simulated exception types and implementation methods: Communication delay simulation: The timer of the core control unit 2 generates an adjustable delay signal within the range of 0-100ms, which is then inserted into the data transmission link via the CAN module. Specific implementation details are as follows: The test process management module issues delay parameters (e.g., 50ms); After receiving the parameters, the communication anomaly simulation unit starts a delay timer before the CAN message is sent; After the timing ends, the message is sent to the electronic power unit under test to simulate the communication delay for a specified duration, with a delay accuracy of ±1ms.

[0062] Data packet loss simulation: A random number algorithm is used to simulate a packet loss rate within the range of 0-5%. Specific logic: Set the packet loss rate parameter (e.g., 3%), and the communication anomaly simulation unit will randomly discard packets according to the set probability during CAN message transmission; The types of messages dropped include UDS command messages and status feedback messages, ensuring the randomness and authenticity of packet loss scenarios; The core control unit 2 records information such as packet loss time and message ID for subsequent data tracing and analysis.

[0063] Bus collision simulation: Bus collision simulation is achieved by generating conflicting messages with the same ID as normal CAN messages but different data segments. The communication anomaly simulation unit monitors the ID and transmission timing of normal messages; While sending normal messages, conflicting messages are sent synchronously, causing abnormal bus levels. The duration of the conflict is adjustable (1-10ms), simulating multi-node communication conflict scenarios in real-world applications.

[0064] Synchronous monitoring and verification logic: Control Unit 2 Coordination: While the core control unit injects an anomaly into the control communication anomaly simulation unit, it simultaneously monitors the operating status of the tested electronic power unit through the sensor feedback module 5 (torque and speed sensor, ECU signal acquisition module, and position sensor). Monitor the ECU's fault feedback signals to determine whether a communication anomaly has been identified (e.g., output a communication fault code). The motor's speed and torque changes are collected by a torque and speed sensor to verify whether the assist performance remains stable under communication failure (torque fluctuation ≤ 0.3 times the average torque). If the tested electronic power unit supports safe degraded operation, monitor whether the degraded operating parameters meet the preset standards; Record the redundancy switching response time after communication anomaly injection (if switching is triggered), and verify that the switching delay is ≤50ms.

[0065] Result determination: The core control unit 2 uploads the monitoring data to the test process management module. The module compares the data with the preset judgment criteria (such as no fault code and stable performance under communication abnormality, or normal operation under safety degradation) and generates the communication reliability verification result. If the criteria are not met, the fault code 0x06 (communication abnormality adaptation fault) is output, and the abnormality type and monitoring data are marked.

[0066] In a preferred embodiment, the control unit 2 is configured to: When driving the actuator 4 to perform the dynamic load test, a closed-loop control strategy combining incremental PID algorithm and torque feedforward compensation technology is adopted. The control unit 2 generates a feedforward compensation signal based on the target load torque change rate and simultaneously performs PID closed-loop correction based on the real-time torque feedback signal collected by the sensing feedback module 5.

[0067] Specifically, the configuration of control unit 2 and the integration of core algorithms are as follows: Control unit 2 uses an ARM Cortex-M7 processor (model: STM32H743VI, main frequency 400MHz), with built-in incremental PID control algorithm module and torque feedforward compensation algorithm module. It outputs control signals through a 16-bit PWM drive module (model: IR2110) with a sampling frequency of 1kHz to ensure the real-time performance and accuracy of dynamic load testing.

[0068] Specific implementation of the closed-loop control strategy: Application of incremental PID algorithm (speed / torque basic control): Algorithm parameters: proportional coefficient Kp=0.8, integral coefficient Ki=0.1, differential coefficient Kd=0.05, which can be adaptively adjusted according to different electronic power unit models under test via host computer software; Control Logic: The core control unit 2 receives the actual speed / torque values ​​uploaded by the sensor feedback module 5 in real time, calculates the deviation between these values ​​and the target values ​​sent by the host computer 1, and calculates the PWM signal duty cycle adjustment using the incremental PID algorithm formula (Δu(k)=Kp[e(k)-e(k-1)]+Ki*e(k)+Kd[e(k)-2e(k-1)+e(k-2)]). This dynamically corrects the output signal, achieving speed fluctuation ≤±5RPM and torque control accuracy ±0.1Nm. Here, e(k) represents the deviation between the target value and the actual value at the current sampling moment, and e(k-1) and e(k-2) represent the deviation values ​​at the previous and two previous sampling moments, respectively.

[0069] Torque feedforward compensation technology (load change adaptive): Feedforward signal generation: Based on historical load data (torque change curve within the last 100ms), control unit 2 predicts the target load torque change rate through a linear fitting algorithm and generates a feedforward compensation signal 0.1ms in advance. The amplitude of the compensation signal is positively correlated with the load change rate (feedforward coefficient 0.8). Cooperative control logic: The feedforward compensation signal and the PID closed-loop correction signal are superimposed and output as the final PWM control signal to the servo load motor driver; when the load changes abruptly from 0Nm to 3Nm, the load growth trend is predicted in advance through feedforward compensation to avoid the response lag of PID control, achieving a load response time of ≤200ms, which is 40% faster than the uncompensated scheme; Dynamic correction: The control unit 2 synchronously receives the real-time torque feedback signal from the sensor feedback module 5 and dynamically corrects the feedforward compensation signal to ensure torque control accuracy (torque fluctuation ≤ 0.2 times the average torque), adapting to dynamic load switching scenarios of "turning in place to high-speed driving".

[0070] Algorithm Collaboration Workflow: Step 1: The host computer 1 issues a dynamic load test command (such as a 3Nm load test), specifying parameters such as the target torque and the rate of load change; Step 2: After the control unit 2 parses the command, the torque feedforward compensation module fits the prediction curve based on historical load data and generates a feedforward compensation PWM signal. Step 3: The sensor feedback module 5 collects the actual torque data of the motor in real time and uploads it to the control unit 2; Step 4: The PID algorithm module calculates the deviation between the target torque and the actual torque, and generates a closed-loop correction signal; Step 5: Control unit 2 superimposes the feedforward compensation signal and the PID correction signal, and outputs the final PWM control signal to the servo load motor to dynamically adjust the load size; Repeat steps 3-5 until the test is completed, ensuring stable load and accurate parameter acquisition throughout the process.

[0071] Furthermore, it also includes a real-time arbitration and isolation circuit; the real-time arbitration and isolation circuit is connected between the control unit 2, the fault simulation module 3 and the electronic power unit under test, and communicates with the test process management module; The real-time arbitration and isolation circuit has at least two operating modes, and the mode switching is controlled by: Mode switching instructions from the test process management module; or / and The circuit makes autonomous judgments based on the state signals it directly acquires regarding the tested electronic power unit or fault injection circuit.

[0072] Furthermore, the control unit 2 is configured to periodically trigger the fault simulation module 3 while driving the actuator 4 to apply a dynamic load to the tested electronic power unit; The fault simulation module 3 is configured to: inject a non-destructive diagnostic signal with an amplitude much smaller than that of the dynamic load into the tested electronic power unit each time it is triggered; The sensing feedback module 5 is configured to: synchronously acquire the response of the tested electronic power unit to the non-destructive diagnostic signal; The control unit 2 is further configured to: calculate and update, in real time, an estimated value of at least one real-time performance parameter of the electronic power unit under test under the dynamic load, based on the response, wherein the real-time performance parameter includes the motor torque constant, back electromotive force constant, or rotor electrical angle offset of the electronic power unit under test.

[0073] Furthermore, the non-destructive diagnostic signal is a voltage perturbation signal based on pseudo-random binary sequence modulation; The fault simulation module 3 is configured to: It generates the fundamental voltage signal through its signal simulation unit; A pseudo-random binary sequence is modulated onto the fundamental voltage signal using amplitude shift keying to form the voltage disturbance signal; Through its power fault injection unit, the voltage disturbance signal is superimposed on the two-phase drive voltage of the motor winding of the tested electronic power unit in a common-mode injection manner; The chip rate of the pseudo-random binary sequence is set to be much higher than the bandwidth of the electronic power unit control system under test, and the peak-to-peak value of the voltage disturbance signal is limited to within 0.5% of the amplitude of the driving voltage.

[0074] Thus, this application addresses the significant shortcomings of existing solutions in the specialized testing of dual-redundant motors: Low calibration accuracy: The zero position is calibrated manually or by traditional self-learning methods, and the error is far higher than the required ≤0.05°; MPS fault detection relies on manual comparison of messages, and the detection rate is low; no special tests are carried out on core parameters such as the performance of the permanent magnet of the motor, the consistency of the winding, and the stability of the ECU power supply in the electronic power unit, making it difficult to ensure that the basic performance of the electronic power unit meets the standards.

[0075] The load simulation is distorted and the scenario is limited: the fixed resistance load cannot reproduce the dynamic load characteristics of "turning in place (95% Fmax) - high speed driving (40% Fmax)"; it can only measure steady-state speed and torque, and cannot capture dynamic parameters such as current fluctuation and torque lag when under load, resulting in missed detection of motor performance problems under the 3Nm extreme working condition.

[0076] The process is fragmented and inefficient: multi-device step-by-step testing takes a long time per unit (unable to meet the mass production requirement of ≤6 minutes); the communication test frame rate is only 2ms / frame, which cannot capture instantaneous anomalies of the electronic power unit within the ≤100μs control cycle; the test data is not interconnected, making it difficult to trace the cause and effect of electronic power unit performance deviations and redundancy switching failures.

[0077] Redundancy safety verification is lacking: Only the basic connectivity of the CAN bus is verified, without simulating abnormal scenarios such as communication delay (0-100ms), packet loss (0-5%), and bus conflict; injection tests for typical electronic power unit faults (sensor signal loss, motor winding short circuit, ECU power supply failure, power module failure) are not carried out, so the effectiveness of fault isolation and redundant takeover cannot be verified, which does not meet the requirements of industry functional safety specifications.

[0078] Therefore, the technical effects that this application can achieve are as follows: Improve calibration accuracy: Achieve zero-point calibration error ≤0.05°, MPS fault detection rate ≥99.5%, ensure that the basic performance of core components such as motor windings, permanent magnets, and ECUs in the electronic power unit meets the standards, and eliminate reliance on manual experience; Reproduces real working conditions: Realizes dynamic load simulation, covering 10-second no-load speed cycle (0→+3000→0→-3000→0RPM) and 3Nm load test, and synchronously collects three-dimensional dynamic parameters such as motor speed-torque-current and ECU control signals in the electronic power unit. Adapted to mass production requirements: Integrated with full-process testing functions for basic performance, redundancy coordination, and fault tolerance of electronic power units, with a single unit testing time of ≤6 minutes; Meeting safety and compliance requirements: Improved communication anomaly simulation and motor fault injection testing, achieving full-scenario verification of redundancy switching, and complying with industry functional safety specifications and steer-by-wire technology requirements.

[0079] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A dual redundant R-EPS steering system electronic power unit performance detection apparatus, characterized by, include: Host computer (1); The control unit (2) is communicatively connected to the host computer (1); The actuator (4) includes a programmable load motor, the control end of which is connected to the control unit (2), and its output end is used to connect to the motor output shaft of the electronic power unit under test; The sensing feedback module (5) includes multiple sensors for collecting the operating parameters of the tested electronic power unit, and each of the sensors is connected to the control unit (2). The fault simulation module (3) is integrated into the control unit (2), and its output is used to connect to the fault injection node of the tested electronic power unit. The programmable load motor, the sensing feedback module (5), and the fault simulation module (3), under the coordination of the control unit (2), constitute an integrated test system for dynamic load testing and active fault injection testing of the electronic power unit under test. The fault simulation module (3) includes a signal simulation unit and a power fault injection unit; The signal simulation unit is configured to: inject simulated signals of sensor signal abnormality or communication bus abnormality into the electronic power unit under test; The power fault injection unit is configured to: inject short-circuit or voltage surge signals into the motor windings or ECU power supply circuit of the electronic power unit under test; The injection action of the fault simulation module (3) and the monitoring action of the sensing feedback module (5) are synchronously controlled by the control unit (2) to verify the fault identification and redundancy switching response of the tested electronic power unit.

2. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 1, wherein, The programmable load motor is a servo motor, and its output shaft is coaxially connected to the motor output shaft of the electronic power unit under test through a rigid coupling. It is used to switch between torque control mode and speed control mode under the control of the control unit (2) to reproduce the dynamic load spectrum of vehicle steering.

3. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 1, wherein, The sensing feedback module (5) includes a torque and speed sensor, a current sensor and a position sensor; The torque and speed sensor is connected in series with the motor output shaft of the electronic power unit under test, and is used to synchronously collect motor torque and speed parameters; The current sensor is connected in series in the motor power supply circuit of the electronic power unit under test, and is used to collect the winding current. The position sensor is set corresponding to the motor rotor of the electronic power unit under test and is used to detect the rotor position.

4. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 1, wherein, It also includes a security protection module, which includes: A hardware emergency stop unit is connected in series in the power supply circuit of the programmable load motor and the electronic power unit under test; The software out-of-tolerance protection unit is integrated into the control unit (2) and is used to compare the data collected by the sensing feedback module (5) with the preset safety threshold in real time, and to trigger the programmable load motor to stop when the out-of-tolerance occurs. The security protection module provides redundant security protection for the dynamic load test and the active fault injection test.

5. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 3, wherein, The sensing feedback module (5) also includes: The insulation resistance detection unit has test probes that are used to connect the motor windings and ECU power supply terminals of the electronic power unit under test, and automatically detect the insulation resistance to ground based on the balanced bridge method. The ECU signal acquisition unit has a pin connector for connecting the control signal output terminal and the fault feedback terminal of the ECU in the tested electronic power unit, and is used to acquire the ECU's PWM control signal and fault status signal in real time.

6. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 1, wherein, It also includes a test process management module that is communicatively connected to the control unit (2); the test process management module is configured to: Send a serialization test command to the control unit (2); Receive and integrate the detection data from the sensing feedback module (5); According to the preset logic, the fault simulation module (3) is triggered to inject a fault at a specific node in the test sequence; The serialized test instructions drive the device to complete electrical safety verification, sensor calibration, dynamic performance testing, and redundancy safety verification.

7. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 6, wherein, The fault simulation module (3) also includes a communication anomaly simulation unit, which is configured to: Under the coordination of the control unit (2), a simulated anomaly is injected into the CAN bus connected to the electronic power unit under test. The simulated anomaly includes at least one of communication delay, data packet loss and bus collision. The control unit (2) synchronously monitors the working status and redundancy switching response of the tested electronic power unit under the simulated abnormality through the sensing feedback module (5).

8. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 6, wherein, The pre-set serialized test instructions in the test process management module drive the device to automatically execute the following detection steps in sequence: Perform preliminary checks to verify the connection status of each module of the equipment and the electronic power unit under test; Perform basic performance pre-tests on the electronic power unit, including insulation resistance, motor winding parameters, and ECU power supply stability testing; Perform MPS calibration, and read and verify position sensor data at a preset speed; Perform zero-position calibration, control the tested motor to learn itself and calculate and write the zero-position deviation; Perform no-load and load dynamic performance tests and collect three-dimensional dynamic parameters of speed, torque and current. Perform fault injection and redundancy switching verification, inject at least one type of fault and verify switching latency and performance retention; Perform communication and system flag verification; The output includes a test report containing all process data and diagnostic results.

9. The dual redundant R-EPS steering system electronic power unit performance test apparatus of claim 8, wherein, The control unit (2) is configured to: When driving the actuator (4) to perform the dynamic load test, a closed-loop control strategy combining incremental PID algorithm and torque feedforward compensation technology is adopted. The control unit (2) generates a feedforward compensation signal based on the target load torque change rate and performs PID closed-loop correction simultaneously based on the real-time torque feedback signal collected by the sensing feedback module (5).

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