A power and digital isolation and fault detection system, detection method

Abstract

The application discloses a kind of power ground and digital ground isolation and fault detection system, detection method, belongs to the field of automobile electronic control, including the power ground layer, digital ground layer and power drive layer being arranged in physical hierarchy, controllable on-off isolation circuit, double-redundancy wake-up control module and double-redundancy state monitoring module are carried on power drive layer, the output end of double-redundancy wake-up control module is connected with controllable on-off isolation circuit, controllable on-off isolation circuit is connected between power ground layer and digital ground layer, and complete electrical isolation and working condition self-adaptive controllable connection of power ground and digital ground are realized by controllable on-off isolation circuit.Power ground and digital ground isolation and fault detection system, detection method described above, reliable electrical isolation of power ground and digital ground, controllable connection of working condition adaptation are realized, while eliminating single-point failure risk and improving fault detection accuracy, adapt to the demand of high stability and high reliability of automobile electronic harsh working condition.

Description

Technical Field

[0001] This invention relates to the field of automotive electronic control technology, and in particular to a power ground and digital ground isolation and fault detection system and method. Background Technology

[0002] With the rapid development of automotive electronics technology, the functions of automotive electronic control units (ECUs) are becoming increasingly complex. This is especially true for core automotive electronic control and execution systems, such as Integrated Brake-by-Wire (GIBC), which place increasingly stringent demands on the functional safety and operational reliability of the equipment. At the grounding design level, as a core component of automotive electronic system design, it directly determines the overall system performance and the integrity of signal transmission. Automotive electronic systems contain different types of grounding terminals, including power ground (including motor power ground and valve power ground) and digital ground. In scenarios where high-power drive circuits and low-power digital control circuits coexist, electromagnetic interference and signal coupling between different grounds can easily cause signal distortion, noise increase, and even directly lead to system failure. In high-power, high-noise on-board conditions like GIBC, the problem of noise propagation across power ground and digital ground is particularly prominent, becoming a key bottleneck restricting stable system operation.

[0003] In traditional automotive electronic system design, the grounding of power ground and digital ground typically employs single-point or multi-point grounding connections to reduce ground loop formation and suppress noise interference. However, this type of grounding design has significant limitations under the complex high-power, high-noise conditions of automotive operation: on the one hand, power ground is prone to generating significant noise due to sudden load changes or circuit faults. This noise can be directly conducted to digital ground through a common ground path, interfering with the normal operation of digital circuits and leading to system malfunctions and functional failures; on the other hand, during system operation, "grounding drops" such as poor grounding connections or broken lines are prone to occur, and existing designs lack effective means to detect such faults, which can easily cause continuous degradation of system performance and, in extreme cases, even lead to driving safety hazards.

[0004] Currently, existing technologies have not achieved effective and complete electrical isolation between power ground and digital ground, and also lack a highly reliable real-time monitoring and fault diagnosis mechanism for grounding failures. Summary of the Invention

[0005] The purpose of this invention is to provide a power ground and digital ground isolation and fault detection system and method to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides a power ground and digital ground isolation and fault detection system, comprising a physically layered power ground layer, a digital ground layer, and a power drive layer. The power drive layer is equipped with a controllable on / off isolation circuit, a dual-redundant wake-up control module, and a dual-redundant status monitoring module. The output of the dual-redundant wake-up control module is connected to the controllable on / off isolation circuit, which is connected between the power ground layer and the digital ground layer. The controllable on / off isolation circuit enables complete electrical isolation between the power ground and the digital ground, as well as adaptive and controllable connection under operating conditions.

[0007] Preferably, the dual-redundant wake-up control module includes a main wake-up unit and an auxiliary wake-up unit that communicate with each other. Both the main wake-up unit and the auxiliary wake-up unit are connected to the system power supply terminal VPWR, and both control the on / off state of the controllable on / off isolation circuit through PWM signals. The power ground layer is isolated from the motor power ground and the valve power ground; The controllable on / off isolation circuit includes a first on / off isolation branch matched with the motor power ground and a second on / off isolation branch matched with the valve power ground. Both the first and second on / off isolation branches include a wake-up control transistor, a drive transistor, a main switch transistor, a voltage divider resistor, and a clamping diode. The gate of the wake-up control transistor receives a PWM signal. The on terminal of the wake-up control transistor is connected to the input terminal of the voltage divider resistor. The output terminal of the voltage divider resistor is connected to the control terminal of the drive transistor. The output terminal of the drive transistor is connected to the control terminal of the main switch transistor. The power terminals of the main switch transistor are connected to the corresponding power ground and digital ground, respectively.

[0008] Preferably, the dual-redundant status monitoring module includes a main monitoring unit and an auxiliary monitoring unit, which are used to determine the connection status of power ground and digital ground by reading the sampled values ​​between the drive transistor and the main switch transistor, and to perform cross-verification; the main monitoring unit is a real-time working unit, and the auxiliary monitoring unit is a backup monitoring unit that takes over the monitoring task when the main monitoring unit fails.

[0009] Preferably, the adaptive controllable connection is implemented based on an adaptive conduction control strategy, and the system collects vehicle speed in real time. Brake pedal travel Power load current Establish a three-level conduction priority and dynamically adjust the PWM signal parameters: Priority 1: and or The PWM signal duty cycle is set to 100%, the main switch is continuously on and the response time is ≤1ms; Priority 2: and or The PWM signal frequency is adaptively adjusted between 500Hz and 1kHz, and the duty cycle is between 50% and 80%. Priority 3: and or The PWM signal frequency is fixed at 300Hz and the duty cycle is 30%.

[0010] The preferred dynamic adjustment strategy for PWM signal parameters is as follows: Digital ground noise amplitude ground connection response time To dynamically adjust the proportional coefficient of the PWM signal to control the target Integral coefficient and differential coefficients ; Among them, the proportionality coefficient , This represents the initial scaling factor. This represents the adjustment value of the proportional coefficient, and Based on noise amplitude and response time deviation Output via a fuzzy rule table; Integral coefficient , This represents the initial scaling factor. This represents the adjustment value for the integral coefficient, and Cumulative value of response time deviation Sure, , Represents the cumulative coefficient of the integral; Differential coefficients , Represents the initial differential coefficients. This represents the adjustment amount of the differential coefficient, and From the rate of change of deviation Sure, , It represents the coefficient of the differential rate of change.

[0011] A detection method for a power ground and digital ground isolation and fault detection system includes the following steps: S1. System initialization: The dual-redundant wake-up control module and dual-redundant status monitoring module perform power-on self-tests, the main wake-up unit and the auxiliary wake-up unit complete communication handshakes, the main monitoring unit starts real-time sampling mode, and the auxiliary monitoring unit starts backup standby mode. S2. The main wake-up unit and the auxiliary wake-up unit send PWM signals to the first on / off isolation branch and the second on / off isolation branch respectively, and verify the validity of the PWM signals. After passing the verification, they execute step S3. S3. Dual-channel interlock wake-up verification: After the main wake-up unit outputs a PWM signal, it waits for the feedback confirmation signal from the auxiliary wake-up unit within 5ms. After the auxiliary wake-up unit outputs a PWM signal, it waits for the feedback confirmation signal from the main wake-up unit within 5ms. If both channels receive feedback, proceed to step S4. If no feedback is received from a single channel, perform a single-channel forced wake-up, record the fault information, and trigger a level one warning. S4. Controllable on / off isolation circuit drive: After the wake-up control tube receives a valid PWM signal, it turns on. The voltage divider signal formed by the voltage divider resistor drives the drive tube to turn on, thereby enabling the gate of the main switch tube to obtain an effective GS voltage difference and turn on, realizing the electrical connection between the motor power ground and digital ground, and between the valve power ground and digital ground. S5, the main monitoring unit, and the auxiliary monitoring unit all convert the acquired analog sampling signal of the ground connection status into a digital signal through an ADC analog-to-digital converter, and use a Kalman filter algorithm to reduce noise in the sampled values, and calculate the standard deviation of nearly 100 noise-reduced sampled values. Update the adaptive dynamic threshold; S6. Hierarchical Fault Diagnosis and Fault-Tolerant Control: Based on the denoised sampled values ​​and adaptive dynamic thresholds, combined with the fault duration, the fault level is determined.

[0012] Preferably, the validity verification strategy described in step S2 is as follows: Set the sliding window length to 10 PWM cycles, count the number of effective wake-up pulses with an amplitude ≥ 4.5V and a pulse width ≥ 50μs within the window, and execute the following control strategy based on the number of effective wake-up pulses: When the number of valid pulses is ≥8, the wake-up signal is determined to be normal and the conduction logic is executed; When the number of valid pulses is less than or equal to 5, the wake-up signal is considered weakly valid, and the PWM signal amplitude is increased from 5V to 5.5V before retrying. When the number of valid pulses is less than 5, the main wake-up failure is determined and the system switches to the secondary wake-up channel.

[0013] Preferably, the adaptive dynamic threshold update strategy described in step S5 is as follows: ; ; In the formula, and These represent the normal connection threshold and the disconnection threshold, respectively. Represents the unit of voltage; This represents the standard deviation of nearly 100 noise-reduced sample values; Preferably, the fault level determination logic in step S6 is as follows: If the real-time acquisition values ​​of both the main monitoring unit and the auxiliary monitoring unit are ≥ And the duration of the fault If the power ground and digital ground are in a normal connection state, the fault duration timer is cleared, and the current controllable on / off isolation circuit conduction strategy is maintained. If the real-time acquisition values ​​of both the main monitoring unit and the auxiliary monitoring unit are within... and If the values ​​collected by the main monitoring unit and the auxiliary monitoring unit deviate from the threshold in a single path, dual redundancy cross-validation is initiated. If the verification is consistent, it is determined to be a poor contact condition, and the fault duration timer is started. If the real-time collected values ​​of the main monitoring unit and the auxiliary monitoring unit are both If the fault is detected, the system is determined to be in a disconnected state, and the fault duration timer is started synchronously. If only a single channel is collected, the value is... If the sampling is abnormal, the monitoring channel is identified as abnormal, and the data collected by another monitoring unit is used as the basis for judgment. The sampling channel is then marked as faulty.

[0014] Therefore, the present invention employs the above-described power ground and digital ground isolation and fault detection system and method, which has the following beneficial effects: 1. Optimize electrical isolation performance and improve signal integrity: Through the physical layering design of power ground and digital ground, combined with controllable switching isolation circuit, complete electrical isolation between power ground and digital ground is achieved under normal operating conditions, blocking the propagation path of high power circuit noise to low power digital circuit, effectively improving the system's anti-interference capability and the integrity of signal sampling. 2. Achieve accurate and reliable ground wire status monitoring: Relying on the main and auxiliary cross-sampling and Kalman filter noise reduction algorithm of the dual redundant status monitoring module, combined with the adaptive dynamic threshold judgment strategy based on standard deviation, the connection status of power ground and digital ground is monitored in real time and accurately. Faults such as momentary disconnection, poor contact, and permanent disconnection are quickly identified and graded protection measures are triggered to avoid safety hazards caused by ground wire failure in the system. 3. Enhance system functional safety and operational reliability: Through a dual-redundant wake-up-monitoring hardware redundancy architecture, a dual-channel interlock wake-up control strategy, and hierarchical fault diagnosis and fault-tolerant control logic, the system is ensured to operate stably under harsh automotive conditions such as high noise, temperature change, and vibration, meeting automotive functional safety standards such as ISO26262, and significantly improving system functional safety and operational reliability. 4. Optimize cost and engineering adaptability: While ensuring high-performance isolation and high-reliability monitoring, the system reduces reliance on high-cost dedicated isolation devices by optimizing the controllable on / off isolation circuit and dual-redundant module design, thereby reducing the overall system complexity and material costs and adapting to the large-scale mass production of automotive electronics and complex real-world application scenarios.

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] Figure 1 This is a circuit diagram of a power ground and digital ground isolation and fault detection system according to the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0018] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0019] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0020] like Figure 1 As shown, a power ground and digital ground isolation and fault detection system includes a physically layered power ground layer, a digital ground layer, and a power drive layer (physical isolation). The power drive layer is equipped with a controllable on / off isolation circuit, a dual-redundant wake-up control module, and a dual-redundant status monitoring module. The output of the dual-redundant wake-up control module is connected to the controllable on / off isolation circuit, which is connected between the power ground layer and the digital ground layer. The controllable on / off isolation circuit achieves complete electrical isolation between the power ground and the digital ground and adaptive controllable connection under operating conditions (electrical isolation).

[0021] The dual-redundant wake-up control module includes a main wake-up unit and an auxiliary wake-up unit that communicate with each other. Both the main wake-up unit and the auxiliary wake-up unit are connected to the system power supply terminal VPWR, and both control the on / off state of the controllable on / off isolation circuit through PWM signals. The power ground layer is isolated from the motor power ground and the valve power ground; The controllable on / off isolation circuit includes a first on / off isolation branch matched with the motor power ground and a second on / off isolation branch matched with the valve power ground. Both the first and second on / off isolation branches include wake-up control transistors (Q5, Q6), drive transistors (Q2, Q4), main switch transistors (Q1, Q3), voltage divider resistors (R1 and R4, R7 and R8), and clamping diodes (D2, D4). The gate of the wake-up control transistor receives the PWM signal. The on terminal of the wake-up control transistor is connected to the input terminal of the voltage divider resistor. The output terminal of the voltage divider resistor is connected to the control terminal of the drive transistor. The output terminal of the drive transistor is connected to the control terminal of the main switch transistor. The power terminals of the main switch transistor are connected to the corresponding power ground and digital ground, respectively.

[0022] The dual-redundant status monitoring module includes a main monitoring unit and an auxiliary monitoring unit. It is used to determine the connection status of power ground and digital ground by reading the sampled values ​​between the drive transistor and the main switch transistor, and to perform cross-verification. The main monitoring unit is a real-time working unit, and the auxiliary monitoring unit is a backup monitoring unit that takes over the monitoring task when the main monitoring unit fails.

[0023] The adaptive controllable connection is implemented based on an adaptive conduction control strategy, and the system collects vehicle speed in real time. Brake pedal travel Power load current Establish a three-level conduction priority and dynamically adjust the PWM signal parameters: Priority 1: and or (Emergency condition) The PWM signal duty cycle is set to 100%, the main switch is continuously on and the response time is ≤1ms; Priority 2: and or (Under normal operating conditions), the PWM signal frequency is adaptively adjusted between 500Hz and 1kHz, and the duty cycle is between 50% and 80%. Priority 3: and or (Under mild operating conditions) The PWM signal frequency is fixed at 300Hz and the duty cycle is 30%.

[0024] The dynamic adjustment strategy for PWM signal parameters is as follows: Digital ground noise amplitude ground connection response time To dynamically adjust the proportional coefficient of the PWM signal to control the target Integral coefficient and differential coefficients ; Among them, the proportionality coefficient , This represents the initial scaling factor, in this embodiment, Take 2.5, This indicates the adjustment value of the proportional coefficient, and Based on noise amplitude and response time deviation Output via a fuzzy rule table; Integral coefficient , This represents the initial scaling factor, in this embodiment, Take 0.1, This represents the adjustment value for the integral coefficient, and Cumulative value of response time deviation Sure, , Represents the cumulative coefficient of the integral; Differential coefficients , In this embodiment, the initial differential coefficients are represented. Take 0.5, This represents the adjustment amount of the differential coefficient, and From the rate of change of deviation Sure, , It represents the coefficient of the differential rate of change.

[0025] This algorithm enables the digital ground noise amplitude to be stably controlled within ±10mV, with a response time fluctuation of ≤0.2ms.

[0026] A method for detecting the isolation and fault detection system between power ground and digital ground includes the following steps: S1. System initialization: The dual-redundant wake-up control module and dual-redundant status monitoring module perform power-on self-tests, the main wake-up unit and the auxiliary wake-up unit complete communication handshakes, the main monitoring unit starts real-time sampling mode, and the auxiliary monitoring unit starts backup standby mode. S2. The main wake-up unit and the auxiliary wake-up unit send PWM signals to the first on / off isolation branch and the second on / off isolation branch respectively, and verify the validity of the PWM signals. After passing the verification, they execute step S3. S3. Dual-channel interlock wake-up verification: After the main wake-up unit outputs a PWM signal, it waits for the feedback confirmation signal from the auxiliary wake-up unit within 5ms. After the auxiliary wake-up unit outputs a PWM signal, it waits for the feedback confirmation signal from the main wake-up unit within 5ms. If both channels receive feedback, proceed to step S4. If no feedback is received from a single channel, perform a single-channel forced wake-up, record the fault information, and trigger a level one warning. S4. Controllable on / off isolation circuit drive: After the wake-up control tube receives a valid PWM signal, it turns on. The voltage divider signal formed by the voltage divider resistor drives the drive tube to turn on, thereby enabling the gate of the main switch tube to obtain an effective GS voltage difference and turn on, realizing the electrical connection between the motor power ground and digital ground, and between the valve power ground and digital ground. S5, the main monitoring unit, and the auxiliary monitoring unit all convert the acquired analog sampling signal of the ground connection status into a digital signal through an ADC analog-to-digital converter, and use a Kalman filter algorithm to reduce noise in the sampled values, and calculate the standard deviation of nearly 100 noise-reduced sampled values. Update the adaptive dynamic threshold; S6. Hierarchical Fault Diagnosis and Fault-Tolerant Control: Based on the denoised sampled values ​​and adaptive dynamic thresholds, combined with the fault duration, the fault level is determined.

[0027] The validity verification strategy described in step S2 is as follows: Set the sliding window length to 10 PWM cycles, count the number of effective wake-up pulses with an amplitude ≥ 4.5V and a pulse width ≥ 50μs within the window, and execute the following control strategy based on the number of effective wake-up pulses: When the number of valid pulses is ≥8, the wake-up signal is determined to be normal and the conduction logic is executed; When the number of valid pulses is less than or equal to 5, the wake-up signal is considered weakly valid, and the PWM signal amplitude is increased from 5V to 5.5V before retrying. When the number of valid pulses is less than 5, the main wake-up failure is determined and the system switches to the secondary wake-up channel.

[0028] Preferably, the adaptive dynamic threshold update strategy described in step S5 is as follows: ; ; In the formula, and These represent the normal connection threshold and the disconnection threshold, respectively. Represents the unit of voltage; This represents the standard deviation of nearly 100 noise-reduced sample values; The fault level determination logic described in step S6 is as follows: If the real-time acquisition values ​​of both the main monitoring unit and the auxiliary monitoring unit are ≥ And the duration of the fault If the power ground and digital ground are in a normal connection state, the fault duration timer is cleared, and the current controllable on / off isolation circuit conduction strategy is maintained. If the real-time acquisition values ​​of both the main monitoring unit and the auxiliary monitoring unit are within... and If the values ​​collected by the main monitoring unit and the auxiliary monitoring unit deviate from the threshold in a single path, dual redundancy cross-validation is initiated. If the verification is consistent, it is determined to be a poor contact condition, and the fault duration timer is started. If the real-time collected values ​​of the main monitoring unit and the auxiliary monitoring unit are both If the fault is detected, the system is determined to be in a disconnected state, and the fault duration timer is started synchronously. If only a single channel is collected, the value is... If the sampling is abnormal, the monitoring channel is identified as abnormal, and the data collected by another monitoring unit is used as the basis for judgment. The sampling channel is then marked as faulty.

[0029] Experimental Example I. Experimental Conditions: The power ground and digital ground isolation and fault detection system of this invention includes dual power ground loops (motor power ground PGND_MR, valve power ground PGND_COIL), a controllable on / off isolation circuit, a dual-redundant wake-up control module, and a dual-redundant status monitoring module; Fault simulation node: motor power ground PGND_MR loop (simulating a disconnection fault scenario); System operating voltage: 12VDC; Load configuration: valve power ground PGND_COIL loop connected in series with a 4.7kΩ load resistor; Measurement and monitoring points: the connection node between digital ground (GND) and valve power ground PGND_COIL, and the sampling channels (G30P_DET_MON, G30V_DET_MON) of the dual-redundant status monitoring module.

[0030] II. Experimental Procedure: Conduct the test and record the experimental data according to the present invention.

[0031] III. Experimental Results and Analysis: Loop current accuracy verification: The measured PGND_COIL loop current is 2.56mA, while the theoretical calculated value is 12V / 4.7kΩ≈2.553mA. The error between the measured value and the theoretical value is only 0.27%, which is within the allowable error range of the system. This proves that the current control accuracy under the adaptive conduction control strategy meets the design requirements.

[0032] Verification of power ground independence and isolation effect: When the PGND_MR loop simulates a disconnection fault, the PGND_COIL loop current remains stable without significant fluctuations; no significant noise crosstalk is detected between the two power grounds; the digital ground potential fluctuation is less than ±10mV, verifying the physical and electrical isolation effect between the power ground layer and the digital ground layer, as well as the independent operation capability of the dual power grounds.

[0033] MOSFET switching performance verification: In the on state (PGND_COIL circuit Q3 is on), the main switch VDS voltage difference is 0V, indicating that the on-resistance is extremely low and the power loss is small; in the off state (PGND_MR circuit Q1 is off), the main switch VDS voltage difference is 12V, which is consistent with the system operating voltage, proving that the turn-off is reliable and there is no risk of leakage current.

[0034] Fault detection accuracy verification: The sampled values ​​of the PGND_MR loop acquired by the dual-redundant condition monitoring module are all ≤ If the fault duration is ≥10ms, it is classified as a Level 3 fault (permanent disconnection); simultaneously, the sampled values ​​of the PGND_COIL circuit are all ≥ The connection was determined to be normal, and the fault diagnosis results were consistent with the simulation scenario, with no misjudgments or omissions.

[0035] IV. Experimental Conclusions: This experimental example verifies the performance of the power ground and digital ground isolation and fault detection system described in this invention in terms of independent operation of dual power grounds, accurate fault detection, and reliable MOSFET switching. Experimental data shows that the system can effectively achieve electrical isolation between power ground and digital ground, controllable connection adapted to operating conditions, and accurate fault diagnosis, meeting the high stability and high reliability requirements of automotive electronics under harsh operating conditions.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A power ground and digital ground isolation and fault detection system, characterized in that: It includes a physically layered power ground layer, a digital ground layer, and a power drive layer. The power drive layer is equipped with a controllable on / off isolation circuit, a dual-redundant wake-up control module, and a dual-redundant status monitoring module. The output of the dual-redundant wake-up control module is connected to the controllable on / off isolation circuit, which is connected between the power ground layer and the digital ground layer. The controllable on / off isolation circuit achieves complete electrical isolation between the power ground and the digital ground, as well as adaptive and controllable connection under operating conditions.

2. The power ground and digital ground isolation and fault detection system according to claim 1, characterized in that: The dual-redundant wake-up control module includes a main wake-up unit and an auxiliary wake-up unit that communicate with each other. Both the main wake-up unit and the auxiliary wake-up unit are connected to the system power supply terminal VPWR, and both control the on / off state of the controllable on / off isolation circuit through PWM signals. The power ground layer is isolated from the motor power ground and the valve power ground; The controllable on / off isolation circuit includes a first on / off isolation branch matched with the motor power ground and a second on / off isolation branch matched with the valve power ground. Both the first and second on / off isolation branches include a wake-up control transistor, a drive transistor, a main switch transistor, a voltage divider resistor, and a clamping diode. The gate of the wake-up control transistor receives a PWM signal. The on terminal of the wake-up control transistor is connected to the input terminal of the voltage divider resistor. The output terminal of the voltage divider resistor is connected to the control terminal of the drive transistor. The output terminal of the drive transistor is connected to the control terminal of the main switch transistor. The power terminals of the main switch transistor are connected to the corresponding power ground and digital ground, respectively.

3. The power ground and digital ground isolation and fault detection system according to claim 2, characterized in that: The dual-redundant status monitoring module includes a main monitoring unit and an auxiliary monitoring unit. It is used to determine the connection status of power ground and digital ground by reading the sampled values ​​between the drive transistor and the main switch transistor, and to perform cross-verification. The main monitoring unit is a real-time working unit, and the auxiliary monitoring unit is a backup monitoring unit that takes over the monitoring task when the main monitoring unit fails.

4. The power ground and digital ground isolation and fault detection system according to claim 3, characterized in that: The adaptive controllable connection is implemented based on an adaptive conduction control strategy, and the system collects vehicle speed in real time. Brake pedal travel Power load current Establish a three-level conduction priority and dynamically adjust the PWM signal parameters: Priority 1: and or The PWM signal duty cycle is set to 100%, the main switch is continuously on and the response time is ≤1ms; Priority 2: and or The PWM signal frequency is adaptively adjusted between 500Hz and 1kHz, and the duty cycle is between 50% and 80%. Priority 3: and or The PWM signal frequency is fixed at 300Hz and the duty cycle is 30%.

5. The power ground and digital ground isolation and fault detection system according to claim 4, characterized in that: The dynamic adjustment strategy for PWM signal parameters is as follows: Digital ground noise amplitude ground connection response time To dynamically adjust the proportional coefficient of the PWM signal to control the target Integral coefficient and differential coefficients ; Among them, the proportionality coefficient , This represents the initial scaling factor. This represents the adjustment value of the proportional coefficient, and Based on noise amplitude and response time deviation Output via a fuzzy rule table; Integral coefficient , This represents the initial scaling factor. This represents the adjustment value for the integral coefficient, and Cumulative value of response time deviation Sure, , Represents the cumulative coefficient of the integral; Differential coefficients , Represents the initial differential coefficients. This represents the adjustment amount of the differential coefficient, and From the rate of change of deviation Sure, , It represents the coefficient of the differential rate of change.

6. The detection method for a power ground and digital ground isolation and fault detection system as described in any one of claims 3-5, characterized in that: Includes the following steps: S1. System initialization: The dual-redundant wake-up control module and dual-redundant status monitoring module perform power-on self-tests, the main wake-up unit and the auxiliary wake-up unit complete communication handshakes, the main monitoring unit starts real-time sampling mode, and the auxiliary monitoring unit starts backup standby mode. S2. The main wake-up unit and the auxiliary wake-up unit send PWM signals to the first on / off isolation branch and the second on / off isolation branch respectively, and verify the validity of the PWM signals. After passing the verification, they execute step S3. S3. Dual-channel interlock wake-up verification: After the main wake-up unit outputs a PWM signal, it waits for the feedback confirmation signal from the auxiliary wake-up unit within 5ms. After the auxiliary wake-up unit outputs a PWM signal, it waits for the feedback confirmation signal from the main wake-up unit within 5ms. If both channels receive feedback, proceed to step S4. If no feedback is received from a single channel, perform a single-channel forced wake-up, record the fault information, and trigger a level one warning. S4. Controllable on / off isolation circuit drive: After the wake-up control tube receives a valid PWM signal, it turns on. The voltage divider signal formed by the voltage divider resistor drives the drive tube to turn on, thereby enabling the gate of the main switch tube to obtain an effective GS voltage difference and turn on, realizing the electrical connection between the motor power ground and digital ground, and between the valve power ground and digital ground. S5, the main monitoring unit, and the auxiliary monitoring unit all convert the acquired analog sampling signal of the ground connection status into a digital signal through an ADC analog-to-digital converter, and use a Kalman filter algorithm to reduce noise in the sampled values, and calculate the standard deviation of nearly 100 noise-reduced sampled values. Update the adaptive dynamic threshold; S6. Hierarchical Fault Diagnosis and Fault-Tolerant Control: Based on the denoised sampled values ​​and adaptive dynamic thresholds, combined with the fault duration, the fault level is determined.

7. The detection method for a power ground and digital ground isolation and fault detection system according to claim 6, characterized in that: The validity verification strategy described in step S2 is as follows: Set the sliding window length to 10 PWM cycles, count the number of effective wake-up pulses with an amplitude ≥ 4.5V and a pulse width ≥ 50μs within the window, and execute the following control strategy based on the number of effective wake-up pulses: When the number of valid pulses is ≥8, the wake-up signal is determined to be normal and the conduction logic is executed; When the number of valid pulses is less than or equal to 5, the wake-up signal is considered weakly valid, and the PWM signal amplitude is increased from 5V to 5.5V before retrying. When the number of valid pulses is less than 5, the main wake-up failure is determined and the system switches to the secondary wake-up channel.

8. The detection method of the power ground and digital ground isolation and fault detection system according to claim 6, characterized in that: The adaptive dynamic threshold update strategy described in step S5 is as follows: ； ； In the formula, and These represent the normal connection threshold and the disconnection threshold, respectively. Represents the unit of voltage; This represents the standard deviation of nearly 100 noise-reduced sample values.

9. The detection method of the power ground and digital ground isolation and fault detection system according to claim 8, characterized in that: The fault level determination logic described in step S6 is as follows: If the real-time acquisition values ​​of both the main monitoring unit and the auxiliary monitoring unit are ≥ And the duration of the fault If the power ground and digital ground are in a normal connection state, the fault duration timer is cleared, and the current controllable on / off isolation circuit conduction strategy is maintained. If the real-time acquisition values ​​of both the main monitoring unit and the auxiliary monitoring unit are within... and If the values ​​collected by the main monitoring unit and the auxiliary monitoring unit deviate from the threshold in a single path, dual redundancy cross-validation is initiated. If the verification is consistent, it is determined to be a poor contact condition, and the fault duration timer is started. If the real-time collected values ​​of the main monitoring unit and the auxiliary monitoring unit are both If the fault is detected, the system is determined to be in a disconnected state, and the fault duration timer is started synchronously. If only a single channel is collected, the value is If the sampling is abnormal, the monitoring channel is identified as abnormal, and the data collected by another monitoring unit is used as the basis for judgment. The sampling channel is then marked as faulty.

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