Self-adaptive priority redundant power supply method and system for chassis key actuator

Abstract

The invention discloses a chassis key actuator-oriented adaptive priority redundant power supply method and system, and relates to the technical field of chassis drive-by-wire, input end voltage, node voltage and link current of a double-path power supply link are collected, recursive filtering is carried out, an impedance value is constructed based on voltage drop and current, and the line health degree is calculated by combining baseline impedance; generating a residual capacity coefficient according to the output power and the maximum power, and identifying a vehicle running state; generating a fault mark through continuous confirmation by using the filtering voltage and the health degree, calculating distributable total power based on a spare link residual capacity coefficient, and setting a priority coefficient to generate a target power upper limit and a power supply sequence; isolation is performed on a fault link through residual current and voltage drop, bus discharge is performed in a motor branch, and the duty ratio slope is associated with a residual capacity coefficient to complete soft start and determine stable power supply; and mapping the power upper limit into a torque upper limit, an action frequency and a permission condition, and executing cooperative control and returning.

Description

Technical Field

[0001] This invention relates to the field of chassis drive-by-wire technology, and more specifically, to an adaptive priority redundant power supply method and system for key chassis actuators. Background Technology

[0002] With the rapid development of automotive intelligence and electrification, chassis brake-by-wire systems are gradually evolving from traditional hydraulic power steering to integrated electro-hydraulic braking systems. The new generation of chassis actuators, represented by the One-box integrated braking system, integrates multiple key actuators such as motor-driven pressure build-up, solenoid valve group pressure regulation, and electronic parking brake into the same control unit. It usually adopts a dual-redundant power supply architecture, that is, two independent power supply links provide power to the actuators respectively, so as to ensure that the system still has basic braking function when a single power supply fails. The dual-redundant power supply architecture has been widely used in mass production line brake systems. Its core idea is that when the main power supply link fails, the backup power supply link takes over all the load, thereby maintaining the continuous operation of the braking system. Upper-level chassis control functions such as ABS anti-lock braking, ESP electronic stability control, TCS traction control, AVH automatic parking, and HDC hill descent control place increasingly higher demands on power supply continuity and power response capabilities.

[0003] The existing technology has the following shortcomings: In the fault diagnosis stage, undervoltage detection is usually based solely on a single voltage threshold, lacking the ability to identify latent faults such as gradual degradation of link impedance. This can easily lead to missed or misdiagnosed faults. During power supply switching, a hard switching method of directly closing the backup link is commonly used, without considering the potential difference impact caused by residual charge on the three-phase motor drive axle bus. This can easily cause inrush current impact and stress damage to power devices. After the backup power supply link takes over, it usually operates in full power supply mode without differentiating power allocation and priority management for different actuators based on the actual remaining power supply capacity of the backup link and the current vehicle operating conditions. This results in the inability to reasonably guarantee the priority operation of the most critical actuators under different operating conditions when the backup link power supply capacity is limited. Furthermore, the current power supply boundary is not fed back to the chassis main controller to achieve coordinated degradation of upper and lower level control functions, thereby affecting the braking safety and functional availability of the entire vehicle in degraded operation mode.

[0004] To address the above problems, this invention proposes a solution. Summary of the Invention

[0005] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide an adaptive priority redundant power supply method and system for chassis key actuators, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An adaptive priority redundancy power supply method for chassis-critical actuators includes the following steps: Step S1: Synchronously collect the input terminal voltage, load-side node voltage and link current of the dual power supply link, perform recursive filtering, construct impedance measurement values ​​based on link voltage drop and current, calculate the line health by combining the baseline impedance under healthy operating conditions, generate the remaining capacity coefficient based on the current output power and the maximum allowable power, and identify the vehicle operating status. Step S2: Use the load-side filter voltage and line health to set a continuous confirmation cycle to generate a fault flag, calculate the total allocable power based on the remaining capacity coefficient of the backup power supply link, set priority coefficients for the motor branch, valve group branch and parking branch according to the vehicle operating status, calculate the target power upper limit for each branch and generate the target power supply sequence from large to small. Step S3: Perform safety isolation on the faulty link through residual current and node voltage drop. When the target branch is a motor branch, perform active bus discharge. Determine the discharge is completed based on the bus residual voltage attenuation and the access potential difference. Correlate the duty cycle growth slope with the remaining capacity coefficient. Complete soft start and determine stable power supply status through the access point voltage deviation and the target branch current change rate. Step S4: Map the target power limit of the motor branch to the torque limit, map the target power limit of the valve group branch to the maximum operating frequency, map the target power limit of the parking branch to the operating permission condition, perform differentiated collaborative control according to the vehicle operating status, and send the power supply boundary back to the chassis main controller.

[0007] In a preferred embodiment, the input voltage, load-side node voltage, and link current of the dual-power supply link are synchronously acquired, and recursive filtering is performed on the input voltage, load-side node voltage, and link current respectively. Recursive filtering uses a weighted combination of the original sampled value of the current sampling period and the filtered value of the previous sampling period to obtain the filtered voltage and filtered current; The link voltage drop is calculated based on the difference between the input filter voltage and the load-side node filter voltage, and the ratio of the link voltage drop to the filter current is used to construct the impedance measurement value. The line health is calculated by combining the baseline impedance recorded under healthy operating conditions with the current impedance estimate.

[0008] In a preferred embodiment, the current link output power is calculated based on the product of the load-side node filter voltage and the filter current. The remaining capacity factor is generated by using the ratio of the difference between the maximum power allowed for continuous power supply and the current output power to the maximum power, and the remaining capacity factor is limited to a range that is not less than zero. The vehicle's operating status is identified, including normal braking conditions, dynamic intervention conditions, and parking holding conditions. The vehicle's operating status is obtained from the internal state variables of the braking system or the functional status flags sent by the chassis main controller.

[0009] In a preferred embodiment, the load-side filter voltage is compared with the power supply failure voltage threshold, and a voltage failure judgment flag is generated when the load-side filter voltage is lower than the power supply failure voltage threshold. The line health status is compared with the health status fault threshold. When the line health status is lower than the health status fault threshold, a health status abnormality judgment flag is generated. Set a continuous confirmation cycle. If either the pressure loss judgment flag or the health abnormality judgment flag is continuously satisfied within the number of continuous confirmation cycles, a final fault flag is generated. The pressure loss judgment flag is used to identify overt pressure loss, and the health abnormality judgment flag is used to identify latent deterioration. When a power supply link is determined to be faulty, another power supply link is designated as a backup power supply link. The total power that can be allocated is calculated by multiplying the remaining capacity factor of the backup power supply link by the maximum power that it is allowed to continuously supply.

[0010] In a preferred embodiment, priority coefficients are set for the motor branch, valve group branch and parking branch according to the vehicle operating status, and each priority coefficient satisfies the normalization constraint. The target power limit for each branch is equal to the product of the corresponding priority coefficient and the total allocable power; The target power supply sequence is generated by sorting the target power limits of each branch from largest to smallest.

[0011] In a preferred embodiment, safety isolation is performed on the faulty link, and the absolute value of the residual current of the faulty link and the deviation between the load-side node filter voltage and the reference shutdown voltage are monitored. When the absolute value of the residual current does not exceed the isolation residual current threshold and the voltage deviation does not exceed the isolation voltage deviation threshold, the isolation is determined to be complete. When the target branch is the motor branch, the closed discharge circuit releases the residual charge on the bus. The residual voltage on the bus decreases according to the exponential decay law, and the discharge time is estimated based on the equivalent discharge resistance of the discharge circuit, the equivalent capacitance of the bus, and the discharge termination voltage threshold. Calculate the connection potential difference between the backup power supply link output terminal and the motor bus. When the bus residual voltage does not exceed the discharge termination voltage threshold or the connection potential difference does not exceed the allowable connection potential difference threshold, the active discharge is determined to be complete.

[0012] In a preferred embodiment, after the active discharge is completed, the soft access phase is entered, and the duty cycle growth slope is linearly correlated with the remaining capacity coefficient of the backup power supply link, with the duty cycle growth slope between the minimum duty cycle slope and the maximum duty cycle slope. The duty cycle of the target switching device increases incrementally from the initial duty cycle at a fixed slope, and is limited to not exceeding the maximum duty cycle. Monitor the voltage deviation at the access point and the rate of change of the target branch current. The voltage deviation at the access point is the ratio of the difference between the filter voltage of the load-side node of the backup power supply link and the voltage of the target access point to the filter voltage of the load-side node of the backup power supply link. The rate of change of the target branch current is the ratio of the difference between the target branch currents in adjacent sampling periods to the upper limit of the allowable current of the target branch. When the voltage deviation at the access point does not exceed the voltage deviation threshold and the current change rate of the target branch does not exceed the current change rate threshold, the power supply is determined to be in a stable state.

[0013] In a preferred embodiment, the upper limit of the target power of the motor branch is mapped to the upper limit of the allowable torque of the motor branch through the energy conversion efficiency coefficient of the motor branch and the motor speed, wherein the motor speed is taken as the larger value between the current motor speed and the minimum speed threshold, and the upper limit of the allowable torque is further mapped to the upper limit of the allowable current of the motor branch through the motor torque constant. The target power limit of the valve group branch is mapped to the maximum allowable operating frequency of the valve group branch by the average equivalent energy of a single valve action. The target power limit of the parking branch is compared with the average power requirement required for the parking branch to complete one lock-up establishment. When the target power limit is not less than the average power requirement, a parking branch action permission flag is generated.

[0014] In a preferred embodiment, when the vehicle is in dynamic intervention mode, the valve group branch takes priority, the motor branch limits the output according to the upper limit of the allowable torque or the upper limit of the allowable current, and the parking branch is on standby. When the vehicle is in parking hold mode, the parking branch takes priority. When the parking branch action permission flag is met, the parking branch is allowed to enter active lock-up establishment. The motor branch and valve group branch only maintain the initial hydraulic hold. When the vehicle is in normal braking condition, the motor branch and valve group branch share the braking capacity, while the parking branch is on standby. The single power supply mode flag, target power supply sequence, target power limit of each branch, and available status of key actuators are transmitted back to the chassis main controller, enabling the upper-level control functions to operate collaboratively within the new power supply boundary. The target power upper limit for each branch is updated smoothly. The smooth update uses a weighted combination of the original target power upper limit of the current sampling period and the smoothed target power upper limit of the previous sampling period. An adaptive priority redundant power supply system for key chassis actuators includes: a baseline establishment module, a priority allocation module, a safety isolation access module, and a collaborative degradation control module, with signal connections between the modules; Baseline establishment module: Synchronously collects input terminal voltage, load-side node voltage and link current for dual power supply links, performs recursive filtering, constructs impedance measurement values ​​based on link voltage drop and current, calculates line health by combining healthy operating condition baseline impedance, generates remaining capacity coefficient based on current output power and maximum allowable power, and identifies vehicle operating status; Priority allocation module: It generates fault flags by setting a continuous confirmation cycle based on the load-side filter voltage and line health, calculates the total allocable power based on the remaining capacity coefficient of the backup power supply link, sets priority coefficients for motor branch, valve group branch and parking branch according to the vehicle operating status, calculates the target power upper limit of each branch and generates the target power supply order from large to small. Safety isolation access module: It performs safety isolation on faulty links through residual current and node voltage drop. When the target branch is a motor branch, it performs active bus discharge. It determines the discharge is completed based on the bus residual voltage attenuation and the access potential difference. It correlates the duty cycle growth slope with the remaining capacity coefficient. It completes soft start and determines stable power supply status through the access point voltage deviation and the target branch current change rate. Collaborative Degradation Control Module: Maps the target power limit of the motor branch to the torque limit, the target power limit of the valve group branch to the maximum operating frequency, and the target power limit of the parking branch to the operating permission condition. It performs differentiated collaborative control based on the vehicle's operating status and sends the power supply boundary back to the chassis main controller.

[0015] The technical effects and advantages of the adaptive priority redundancy power supply method for key chassis actuators of this invention are as follows: This invention constructs impedance measurements based on link voltage drop and current, calculates line health by combining baseline impedance under healthy operating conditions, and generates fault flags by setting a continuous confirmation cycle using load-side filter voltage and line health. It employs a fault identification method combining explicit undervoltage and implicit degradation as dual criteria with a continuous confirmation mechanism, effectively avoiding instantaneous misjudgments caused by normal dynamic fluctuations. By performing safety isolation confirmation on the faulty link, and actively discharging the bus when the target branch is a motor branch, the discharging completion condition is determined based on the bus residual voltage attenuation and the access potential difference. Adaptive soft-start access is achieved by correlating the duty cycle growth slope with the remaining capacity coefficient of the backup power supply link. Compared to the hard switching method of directly closing the backup link in existing technologies, this effectively avoids inrush current and power device stress damage caused by potential difference surges. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the adaptive priority redundancy power supply method for key chassis actuators according to the present invention.

[0017] Figure 2 Schematic diagram of dual-criteria fault confirmation and priority power allocation.

[0018] Figure 3 This is a schematic diagram of the adaptive priority redundant power supply system module for key chassis actuators according to the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example Please see Figures 1-3 As shown, this invention discloses an adaptive priority redundancy power supply method for chassis-critical actuators, comprising the following steps: Step S1: Synchronously collect the input terminal voltage, load-side node voltage and link current of the dual power supply link, perform recursive filtering, construct impedance measurement values ​​based on link voltage drop and current, calculate the line health by combining the baseline impedance under healthy operating conditions, generate the remaining capacity coefficient based on the current output power and the maximum allowable power, and identify the vehicle operating status. Step S2: Use the load-side filter voltage and line health to set a continuous confirmation cycle to generate a fault flag, calculate the total allocable power based on the remaining capacity coefficient of the backup power supply link, set priority coefficients for the motor branch, valve group branch and parking branch according to the vehicle operating status, calculate the target power upper limit for each branch and generate the target power supply sequence from large to small. Step S3: Perform safety isolation on the faulty link through residual current and node voltage drop. When the target branch is a motor branch, perform active bus discharge. Determine the discharge is completed based on the bus residual voltage attenuation and the access potential difference. Correlate the duty cycle growth slope with the remaining capacity coefficient. Complete soft start and determine stable power supply status through the access point voltage deviation and the target branch current change rate. Step S4: Map the target power limit of the motor branch to the torque limit, map the target power limit of the valve group branch to the maximum operating frequency, map the target power limit of the parking branch to the operating permission condition, perform differentiated collaborative control according to the vehicle operating status, and send the power supply boundary back to the chassis main controller.

[0021] In step S1, the input voltage, load-side node voltage, and link current of the dual-power supply link are synchronously collected. Recursive filtering is performed, and impedance measurements are constructed based on the link voltage drop and current. The line health is calculated by combining the baseline impedance under healthy operating conditions. The remaining capacity coefficient is generated based on the current output power and the maximum allowable power to identify the vehicle's operating status. Specific details include: This step establishes a unified status baseline for the dual power supply links, enabling rapid identification of abnormal power supply links and determining which link can continue to provide power, thus generating the core parameters needed later, namely, line health. Remaining capacity coefficient And the vehicle's operating status S; In this embodiment, after the system is powered on and enters a stable working state, the MCU synchronously collects the input voltage, load-side node voltage, and link current of the first power supply link and the second power supply link. The three-phase motor branch has a dynamic voltage build-up process, the solenoid valve group branch has a high-frequency engagement action, and the EPB motor group branch has a short-term inrush current. Therefore, the original sampled values ​​cannot be used directly for state judgment. Otherwise, normal dynamic fluctuations may be misjudged as link abnormalities. The input voltage, load-side node voltage, and link current are recursively filtered to obtain stable basic measurement results. For the The input voltage of the power supply link can be expressed by the formula: ;in, For the first The sampling period The filter voltage at the input of the power supply link. For the previous sampling period The filter voltage at the input of the power supply link. For the first The sampling period The original sampling voltage at the input of the power supply link. These are the voltage filtering coefficients; For the The load-side node voltage of the power supply link can be expressed by the formula: ;in, For the first The sampling period Filtered voltage of the load-side node of the power supply link. For the previous sampling period Filtered voltage of the load-side node of the power supply link. For the first The sampling period The original sampled voltage of the load-side node of the power supply link. These are the voltage filtering coefficients; For the The current in the power supply link can be expressed by the formula: ;in, For the first The sampling period Filtering current of the power supply link For the previous sampling period Filtering current of the power supply link For the first The sampling period The original sampling current of the power supply link, These are the current filtering coefficients; After obtaining the filter voltage and filter current, the line health is constructed based on the link voltage drop and link current. The reason for constructing the line health is to compress the health status of the link into a single result. ; Link voltage drop is used to characterize the voltage loss between the power input terminal and the load connection point, and can be expressed by the formula: ;in, For the first The sampling period Voltage drop in the power supply link, For the first The sampling period The filter voltage at the input of the power supply link. For the first The sampling period Filtered voltage at the load-side node of the power supply link; Link impedance measurements are used to normalize the voltage drop to the current dimension, avoiding misjudgments caused solely by increased load current. The formula can be expressed as: ;in, For the first The sampling period Impedance measurements of the power supply link. For the first The sampling period Voltage drop in the power supply link, For the first The sampling period Filtering current of the power supply link A positive decimal is set to prevent the denominator from being zero; In this embodiment, the current impedance estimate From the aforementioned impedance measurements This is obtained. Furthermore, this is combined with the baseline impedance recorded under healthy operating conditions. and current impedance estimate The formula for line health can be expressed as: ;in, For the first The sampling period The health of the power supply link. For the first The baseline impedance of the power supply link under healthy operating conditions. For the first The sampling period The current impedance estimate of the power supply link. A positive decimal is set to prevent the denominator from being zero; To enable a rapid assessment of whether the backup power supply link is capable of taking over, a remaining capacity factor also needs to be generated. In subsequent steps, this is used to generate the target power upper limit for each branch. The current link power formula can be expressed as: ;in, For the first The sampling period The current output power of the power supply link. For the first The sampling period Filtered voltage of the load-side node of the power supply link. For the first The sampling period Filtering current of the power supply link; The formula for the remaining capacity factor can be expressed as: ;in, For the first The sampling period The remaining capacity factor of the power supply link. For the first The maximum power that the power supply link is allowed to continuously supply. For the first The sampling period The current output power of the power supply link; This step identifies the vehicle's operating status. The role of vehicle operating status is that subsequent steps need to generate different target power supply sequence and power distribution results based on whether the current condition is normal braking, dynamic intervention or parking. It should be noted that the vehicle operating status in this embodiment It can be obtained from the internal state variables of the braking system or from the functional status flags sent by the chassis main controller. When in normal braking condition, it is recorded as... When functions such as ABS, ESP, or TCS are activated, it is recorded as When the AVH or parking lock establishment phase is activated, it is recorded as ; Three core results are needed to form the subsequent steps: line health Remaining capacity coefficient and vehicle operating status Among them, the line health is used in step S2 to perform fault confirmation based on the dual criteria of explicit undervoltage and implicit degradation, the remaining capacity coefficient is used in step S2 to generate the allocable power boundary of the backup power supply link, and the vehicle operating status is used in step S2 to form the target power supply sequence and target power limit.

[0022] In step S2, a fault flag is generated by setting a continuous confirmation cycle based on the load-side filter voltage and line health. The total allocable power is calculated based on the remaining capacity coefficient of the backup power supply link. Priority coefficients are set for the motor branch, valve group branch, and parking branch according to the vehicle's operating status. The target power upper limit for each branch is calculated and the target power supply order is generated in descending order. Specific contents include: The parameters generated in step S1 are transformed into executable reconfiguration decisions, specifically answering which power supply link failed, how much power supply capacity the remaining links can still provide, and which type of critical actuators should be prioritized for protection. Since step S1 has already compressed the complex raw quantities into... , and Therefore, this step can complete fault identification and priority power allocation with clearer criteria; Fault confirmation adopts a dual criterion method of load-side voltage and line health. Load-side voltage is used to identify explicit voltage loss, while line health is used to identify implicit degradation states that have not been completely depleted but are no longer suitable for continuing to supply power to critical actuators. For the The undervoltage determination flag for the power supply link can be expressed by the formula: ;in, For the first The sampling period The power supply link undervoltage determination flag, For the first The sampling period Filtered voltage of the load-side node of the power supply link. This refers to the power supply failure voltage threshold. For the The health status criterion for a power supply link can be expressed by the following formula: ;in, For the first The sampling period Health anomaly detection flag for power supply links. For the first The sampling period The health of the power supply link. The health status fault threshold; To avoid misjudgment due to instantaneous fluctuations, this embodiment sets a continuous confirmation period, and the final fault flag formula can be expressed as: ;in, For the first The sampling period The final fault indicator of the power supply link. This represents the number of fault confirmation cycles. For logical OR operation; When one power supply link is determined to be faulty, the other power supply link is designated as the backup power supply link. This step is then based on the remaining capacity factor of the backup power supply link. The purpose of calculating its total allocatable power is to generate implementable power boundaries for subsequent different actuator branches; The formula for the total allocatable power of the backup power supply link can be expressed as: ;in, For the first The total power available for allocation in the backup power supply link per sampling period For the first The remaining capacity factor of the backup power supply link for each sampling period. The maximum power that can be continuously supplied to the backup power link; Since the functional importance of key actuators varies under different operating conditions, the vehicle operating status is identified in step S1. Based on this, priority coefficients are set for the motor branch, valve group branch, and parking branch respectively. And satisfying the normalization constraint, the priority coefficient constraint formula can be expressed as: ;in, The vehicle's operating status is The priority coefficient of the motor branch. The vehicle's operating status is Priority coefficient of the time valve group branch, The vehicle's operating status is Priority coefficient of parking branch road; Furthermore, the formula for the upper limit of the target power of each actuator branch can be expressed as: ;in, For the first The sampling period The target power limit for each load branch The vehicle's operating status is Time Priority coefficient of each load branch, For the first The total power available for allocation in the backup power supply link for each sampling period; After obtaining the target power upper limit for each branch, in order to facilitate direct use in steps S3 and S4, this embodiment generates the target power supply order in descending order of target power upper limit. The formula for the target power supply order can be expressed as: ;in, Power supply sequence for the target For sorting operators that sort in descending order, The upper limit of the target power of the motor branch. The upper limit of the target power for the valve group branch. The target power limit for the parking branch; For example, when the current remaining capacity coefficient of the backup power supply link is 0.639, the maximum allowable continuous power supply is 720 watts, and the vehicle is in dynamic intervention mode, the system can obtain different target power limits for the valve group branch, motor branch and parking branch according to the principle of valve group priority, motor second, and parking standby in dynamic intervention in the briefing, and naturally form the target power supply order of valve group priority. This step uses the output of step S1. , and For direct input, the dual-criteria fault identification, calculation of the total allocable power of the backup power supply link, calculation of the target power limit of each branch, and generation of the target power supply sequence are completed. Therefore, step S3 can directly perform physical power supply reconstruction based on the fault results, target power limit, and target power supply sequence without having to re-analyze the original sampled data. Step S4 can also carry out cooperative degradation operation in single power supply mode on the same target power boundary.

[0023] In step S3, safety isolation is performed on the faulty link through residual current and node voltage drop. When the target branch is a motor branch, active bus discharge is performed. The discharge is determined to be complete based on the bus residual voltage attenuation and the connection potential difference. The duty cycle growth slope is correlated with the remaining capacity coefficient. Soft start is completed and a stable power supply state is determined by the connection point voltage deviation and the target branch current change rate. Specific details include: This step transforms the reconfiguration decision formed in step S2 into an actual power supply path switching. The key is not simply closing the backup link, but first safely isolating the faulty link, then performing active bus discharge when the target branch is a three-phase motor branch, and finally smoothly connecting through PWM soft start based on the remaining capacity of the backup power supply link. When it is necessary to switch power to the three-phase motor load, the MCU first closes the discharge circuit MOSFET to release the residual charge on the bus, and then gradually turns on the target MOSFET in PWM mode, thereby avoiding inrush current and device stress. In this embodiment, safety isolation is performed on the faulty link. To confirm that the original faulty link has been removed from the power supply network, it is necessary to observe its residual current and node voltage drop simultaneously. The formula for the absolute value of the residual current of the faulty link isolation can be expressed as: ;in, For the first The absolute value of the isolation residual current of the faulty link in each sampling period. For the first The filtered current of the faulty link in each sampling period. The formula for the isolation voltage deviation of a faulty link node can be expressed as: ;in, For the first The isolation voltage deviation of the faulty link node in each sampling period For the first The filtered voltage of the load-side node of the faulty link in each sampling period This is the reference shutdown voltage after isolation; The formula for indicating isolation completion can be expressed as: ;in, For the first The completion marker for isolation of each sampling cycle. To isolate the residual current threshold, The isolation voltage deviation threshold; When the target branch is a motor branch, active bus discharge is performed. The reason for using active discharge is that the three-phase motor drive bridge bus has residual charge after power failure. If it is directly connected to the backup power supply link, it is easy to cause potential difference surge. The formula for the bus residual voltage attenuation law can be expressed as: ;in, For time Busbar residual pressure at any moment This represents the initial residual pressure on the busbar at the start of the discharge. The equivalent discharge resistance of the active discharge circuit. This is the equivalent capacitance of the motor drive bridge bus. Duration of the discharge; To estimate the discharge time, the formula can be expressed as: ;in, The theoretical discharge time required to reach the discharge termination voltage threshold. The equivalent discharge resistance of the active discharge circuit. This is the equivalent capacitance of the busbar. The discharge termination voltage threshold, This represents the initial residual pressure on the busbar at the start of the discharge. It is the natural logarithm operator; To further determine whether safe access conditions are met, the potential difference between the backup power supply link output and the motor bus is calculated. The formula can be expressed as: ;in, For the first The connection potential difference between the output terminal of the backup power supply link and the motor bus in each sampling cycle For the first The filtered voltage of the load-side node of the backup power supply link in each sampling period For the first Motor bus residual voltage in one sampling cycle; The formula for determining the completion of active discharge can be expressed as: ;in, For the first The active discharge completion marker for each sampling cycle For the first Motor bus residual voltage per sampling period The discharge termination voltage threshold, For the first The input potential difference is used in each sampling period. To allow access to the specified potential difference threshold; After the active discharge is completed, the PWM soft-access phase begins. The PWM control signal increases at a specific slope starting from a 5% duty cycle, and the maximum power limit of the three-phase motor is set according to the current remaining capacity. Therefore, in this embodiment, the duty cycle growth slope is correlated with the remaining capacity coefficient of the backup power supply link. The formula for the duty cycle growth slope can be expressed as: ;in, For the first The duty cycle growth slope of each control cycle For the minimum duty cycle slope, For the maximum duty cycle slope, For the first The remaining capacity factor of the backup power supply link for each control cycle. The formula for increasing the PWM duty cycle of the target MOSFET can be expressed as: ;in, For the first The duty cycle of the target MOSFET in each PWM control cycle. For maximum duty cycle, The initial duty cycle, For the first The duty cycle growth slope of each control cycle This is the current PWM control cycle number; To determine whether soft access has been completed, this embodiment continues to monitor the access point voltage deviation and the target branch current change rate. The access point voltage deviation formula can be expressed as: ;in, For the first The voltage deviation at the access point in each sampling period. For the first The filtered voltage of the load-side node of the backup power supply link in each sampling period For the first The target access node voltage in each sampling period A positive decimal is set to prevent the denominator from being zero; The formula for the rate of change of the target branch current can be expressed as: ;in, For the first Rate of change of target branch current in each sampling period For the first Target branch current in each sampling period The target branch current in the previous sampling period. The upper limit of the allowable current for the target branch. A positive decimal is set to prevent the denominator from being zero; The formula for determining stable power supply can be expressed as: ;in, For the first The stable power supply judgment value for each sampling period. For the first Voltage deviation at the access point per sampling period This is the voltage deviation threshold. For the first Rate of change of target branch current in each sampling period The threshold for the rate of change of current; By first isolating the faulty link, then performing active discharge of the motor bus, then performing PWM soft connection based on the remaining capacity, and finally determining the stable power supply state, the reconfiguration decision formed in step S2 is implemented as a power supply path switching result that can be safely implemented. Thus, step S4 can continue to perform priority downgrade operation on the already confirmed stable single power supply boundary, without having to deal with the connection transient problem.

[0024] In step S4, the target power upper limit of the motor branch is mapped to the torque upper limit, the target power upper limit of the valve group branch is mapped to the maximum operating frequency, and the target power upper limit of the parking branch is mapped to the operating permission condition. Differentiated cooperative control is performed according to the vehicle operating status, and the power supply boundary is transmitted back to the chassis main controller. The specific content includes: Under the premise that a smooth connection has been completed in step S3, the system continues to operate stably in single power supply mode, instead of simply relying on the backup power supply link to take over all loads. Based on the target power limit and target power supply sequence generated in step S2, the system applies differentiated power limits to the motor branch, valve group branch and parking branch, and feeds back the current power supply boundary to the chassis main controller, so that the upper-level control functions such as ABS, ESP, AVH, HDC and so on can operate collaboratively within the new power supply boundary. When step S3 outputs When entering single-power-supply mode, for the motor branch, the target power limit needs to be further converted into a torque limit that can be directly called by the drive control. The reason is that the three-phase motor is the power source for establishing the One-box braking force, and the actual control is often executed through torque or current boundaries. The formula for the allowable torque limit of the motor branch can be expressed as: ;in, For the first The maximum allowable torque of the motor branch per sampling period The energy conversion efficiency coefficient of the motor branch. For the first The upper limit of the target power of the motor branch in each sampling period For the first Motor speed per sampling period, A minimum speed threshold is set to prevent the denominator from being too small. To select the operator with the larger value; To further map this to a current limit, the formula can be expressed as: ;in, For the first The upper limit of the allowable current of the motor branch in each sampling period For the first The maximum allowable torque of the motor branch per sampling period The torque constant of the motor; For valve group branches, the target power limit needs to be converted into the maximum allowable operating frequency of the valve group. This is because the functions of ABS, ESP, TCS, etc., mainly involve changes in pulse operating frequency and duty cycle density when calling upon the valve group. The formula for the maximum allowable operating frequency of the valve group branch can be expressed as: ;in, For the first The maximum allowable operating frequency of the valve group branch per sampling period For the first The upper limit of the target power of the valve group branch in each sampling period The average equivalent energy of a single valve action; For parking branch circuits, since they typically involve short-duration, high-power actions, using an action authorization method is more direct. The action authorization criterion formula for parking branch circuits can be expressed as: ;in, For the first Parking branch road action permit sign for each sampling cycle, For the first The upper limit of the target power of the parking branch in each sampling period The average power requirement for establishing a lock on a parking branch; According to vehicle operating status Implement differentiated collaborative control: when At that time, the valve group branch takes priority, and the motor branch follows the order of priority. or Output restricted, vehicle parked on side road and ready to go; when At that time, priority is given to parking on side roads, if This allows the parking branch to enter active locking mode, while the motor branch and valve group branch only maintain initial hydraulic pressure. when At the same time, the motor branch and the valve group branch jointly undertake the normal braking capacity, the parking branch is on standby, the valve group takes priority during dynamic intervention, EPB takes priority during parking, and the motor and valve group jointly ensure normal braking. To ensure that the upper chassis control functions are consistent with the current power supply boundary, the single power supply mode flag and target power supply sequence are set. Target power limit for each branch The availability status of key actuators is fed back to the chassis main controller, and upper-level functions such as ABS, ESP, AVH, and HDC can adjust their strategies within the new total power boundary without continuing to make control requests that exceed the current power supply capacity. After entering the single power supply degradation mode, the MCU needs to notify the chassis main controller that the power supply mode has changed and operate stably within the new power boundary. To avoid frequent jitter in upper-layer functions caused by small fluctuations in the target power limit during the control period, this embodiment can also perform a smooth update on the target power limit. The formula for smoothing the target power limit can be expressed as: ;in, For the first The sampling period Smooth target power limit for each load branch For the previous sampling period Smooth target power limit for each load branch For the first The sampling period The original target power limit of each load branch, For smoothing coefficients; The target power limit of the motor branch is mapped to the allowable torque or allowable current boundary, the target power limit of the valve group branch is mapped to the maximum operating frequency, and the target power limit of the parking branch is mapped to the action permission condition. Different priority control logics are executed according to the vehicle operating status. In single power supply mode, it can not only continue to operate, but also prioritize the effectiveness of the most critical chassis functions within the limited power boundary. By feeding back the power supply boundary to the chassis main controller, the upper-level functions can work in coordination with the power supply layer, thereby forming a complete graceful degradation control closed loop.

[0025] This invention discloses an adaptive priority redundancy power supply system for key chassis actuators, comprising: a baseline establishment module, a priority allocation module, a safety isolation access module, and a collaborative degradation control module, with signal connections between the modules; Baseline establishment module: Synchronously collects input terminal voltage, load-side node voltage and link current for dual power supply links, performs recursive filtering, constructs impedance measurement values ​​based on link voltage drop and current, calculates line health by combining healthy operating condition baseline impedance, generates remaining capacity coefficient based on current output power and maximum allowable power, and identifies vehicle operating status; Priority allocation module: It generates fault flags by setting a continuous confirmation cycle based on the load-side filter voltage and line health, calculates the total allocable power based on the remaining capacity coefficient of the backup power supply link, sets priority coefficients for motor branch, valve group branch and parking branch according to the vehicle operating status, calculates the target power upper limit of each branch and generates the target power supply order from large to small. Safety isolation access module: It performs safety isolation on faulty links through residual current and node voltage drop. When the target branch is a motor branch, it performs active bus discharge. It determines the discharge is completed based on the bus residual voltage attenuation and the access potential difference. It correlates the duty cycle growth slope with the remaining capacity coefficient. It completes soft start and determines stable power supply status through the access point voltage deviation and the target branch current change rate. Collaborative Degradation Control Module: Maps the target power limit of the motor branch to the torque limit, the target power limit of the valve group branch to the maximum operating frequency, and the target power limit of the parking branch to the operating permission condition. It performs differentiated collaborative control based on the vehicle's operating status and sends the power supply boundary back to the chassis main controller.

[0026] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0027] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0028] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and inventive constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0029] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0030] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0031] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An adaptive priority redundancy power supply method for key chassis actuators, characterized in that, Including the following steps: Step S1: Synchronously collect the input terminal voltage, load-side node voltage and link current of the dual power supply link, perform recursive filtering, construct impedance measurement values ​​based on link voltage drop and current, calculate the line health by combining the baseline impedance under healthy operating conditions, generate the remaining capacity coefficient based on the current output power and the maximum allowable power, and identify the vehicle operating status. Step S2: Use the load-side filter voltage and line health to set a continuous confirmation cycle to generate a fault flag, calculate the total allocable power based on the remaining capacity coefficient of the backup power supply link, set priority coefficients for the motor branch, valve group branch and parking branch according to the vehicle operating status, calculate the target power upper limit for each branch and generate the target power supply sequence from large to small. Step S3: Perform safety isolation on the faulty link through residual current and node voltage drop. When the target branch is a motor branch, perform active bus discharge. Determine the discharge is completed based on the bus residual voltage attenuation and the access potential difference. Correlate the duty cycle growth slope with the remaining capacity coefficient. Complete soft start and determine stable power supply status through the access point voltage deviation and the target branch current change rate. Step S4: Map the target power limit of the motor branch to the torque limit, map the target power limit of the valve group branch to the maximum operating frequency, map the target power limit of the parking branch to the operating permission condition, perform differentiated collaborative control according to the vehicle operating status, and send the power supply boundary back to the chassis main controller.

2. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 1, characterized in that, The input voltage, load-side node voltage, and link current of the dual-power supply link are synchronously collected, and recursive filtering is performed on the input voltage, load-side node voltage, and link current respectively. Recursive filtering uses a weighted combination of the original sampled value of the current sampling period and the filtered value of the previous sampling period to obtain the filtered voltage and filtered current; The link voltage drop is calculated based on the difference between the input filter voltage and the load-side node filter voltage, and the ratio of the link voltage drop to the filter current is used to construct the impedance measurement value. The line health is calculated by combining the baseline impedance recorded under healthy operating conditions with the current impedance estimate.

3. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 2, characterized in that, The current link output power is calculated based on the product of the filter voltage and filter current at the load-side node. The remaining capacity factor is generated by using the ratio of the difference between the maximum power allowed for continuous power supply and the current output power to the maximum power, and the remaining capacity factor is limited to a range that is not less than zero. The vehicle's operating status is identified, including normal braking conditions, dynamic intervention conditions, and parking holding conditions. The vehicle's operating status is obtained from the internal state variables of the braking system or the functional status flags sent by the chassis main controller.

4. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 1, characterized in that, The load-side filter voltage is compared with the power supply failure voltage threshold. When the load-side filter voltage is lower than the power supply failure voltage threshold, a voltage failure judgment flag is generated. The line health status is compared with the health status fault threshold. When the line health status is lower than the health status fault threshold, a health status abnormality judgment flag is generated. Set a continuous confirmation cycle. If either the pressure loss judgment flag or the health abnormality judgment flag is continuously satisfied within the number of continuous confirmation cycles, a final fault flag is generated. The pressure loss judgment flag is used to identify overt pressure loss, and the health abnormality judgment flag is used to identify latent deterioration. When a power supply link is determined to be faulty, another power supply link is designated as a backup power supply link. The total power that can be allocated is calculated by multiplying the remaining capacity factor of the backup power supply link by the maximum power that it is allowed to continuously supply.

5. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 4, characterized in that, Priority coefficients are set for the motor branch, valve group branch and parking branch according to the vehicle's operating status, and each priority coefficient satisfies the normalization constraint. The target power limit for each branch is equal to the product of the corresponding priority coefficient and the total allocable power; The target power supply sequence is generated by sorting the target power limits of each branch from largest to smallest.

6. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 1, characterized in that, Perform safety isolation on the faulty link, monitor the absolute value of the residual current of the faulty link and the deviation between the load-side node filter voltage and the reference shutdown voltage. When the absolute value of the residual current does not exceed the isolation residual current threshold and the voltage deviation does not exceed the isolation voltage deviation threshold, the isolation is determined to be complete. When the target branch is the motor branch, the closed discharge circuit releases the residual charge on the bus. The residual voltage on the bus decreases according to the exponential decay law, and the discharge time is estimated based on the equivalent discharge resistance of the discharge circuit, the equivalent capacitance of the bus, and the discharge termination voltage threshold. Calculate the connection potential difference between the backup power supply link output terminal and the motor bus. When the bus residual voltage does not exceed the discharge termination voltage threshold or the connection potential difference does not exceed the allowable connection potential difference threshold, the active discharge is determined to be complete.

7. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 6, characterized in that, After the active discharge is completed, the soft access phase begins, where the duty cycle growth slope is linearly correlated with the remaining capacity coefficient of the backup power supply link, and the duty cycle growth slope is between the minimum duty cycle slope and the maximum duty cycle slope. The duty cycle of the target switching device increases incrementally from the initial duty cycle at a fixed slope, and is limited to not exceeding the maximum duty cycle. Monitor the voltage deviation at the access point and the rate of change of the target branch current. The voltage deviation at the access point is the ratio of the difference between the filter voltage of the load-side node of the backup power supply link and the voltage of the target access point to the filter voltage of the load-side node of the backup power supply link. The rate of change of the target branch current is the ratio of the difference between the target branch currents in adjacent sampling periods to the upper limit of the allowable current of the target branch. When the voltage deviation at the access point does not exceed the voltage deviation threshold and the current change rate of the target branch does not exceed the current change rate threshold, the power supply is determined to be in a stable state.

8. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 1, characterized in that, The target power limit of the motor branch is mapped to the allowable torque limit of the motor branch through the energy conversion efficiency coefficient of the motor branch and the motor speed, where the motor speed is taken as the larger value between the current motor speed and the minimum speed threshold. The allowable torque limit is further mapped to the allowable current limit of the motor branch through the motor torque constant. The target power limit of the valve group branch is mapped to the maximum allowable operating frequency of the valve group branch by the average equivalent energy of a single valve action. The target power limit of the parking branch is compared with the average power requirement required for the parking branch to complete one lock-up establishment. When the target power limit is not less than the average power requirement, a parking branch action permission flag is generated.

9. The adaptive priority redundant power supply method for chassis-critical actuators according to claim 8, characterized in that, When the vehicle is in dynamic intervention mode, the valve group branch takes priority, the motor branch outputs according to the upper limit of the allowable torque or the upper limit of the allowable current, and the parking branch is on standby. When the vehicle is in parking hold mode, the parking branch takes priority. When the parking branch action permission flag is met, the parking branch is allowed to enter active lock-up establishment. The motor branch and valve group branch only maintain the initial hydraulic hold. When the vehicle is in normal braking condition, the motor branch and valve group branch share the braking capacity, while the parking branch is on standby. The single power supply mode flag, target power supply sequence, target power limit of each branch, and available status of key actuators are transmitted back to the chassis main controller, enabling the upper-level control functions to operate collaboratively within the new power supply boundary. The target power upper limit of each branch is updated smoothly. The smooth update adopts a weighted combination of the original target power upper limit of the current sampling period and the smoothed target power upper limit of the previous sampling period.

10. An adaptive priority redundancy power supply system for chassis-critical actuators, used to implement the adaptive priority redundancy power supply method for chassis-critical actuators as described in any one of claims 1-9, characterized in that... ； Baseline establishment module: Synchronously collects input terminal voltage, load-side node voltage and link current for dual power supply links, performs recursive filtering, constructs impedance measurement values ​​based on link voltage drop and current, calculates line health by combining healthy operating condition baseline impedance, generates remaining capacity coefficient based on current output power and maximum allowable power, and identifies vehicle operating status; Priority allocation module: It generates fault flags by setting a continuous confirmation cycle based on the load-side filter voltage and line health, calculates the total allocable power based on the remaining capacity coefficient of the backup power supply link, sets priority coefficients for motor branch, valve group branch and parking branch according to the vehicle operating status, calculates the target power upper limit of each branch and generates the target power supply order from large to small. Safety isolation access module: It performs safety isolation on faulty links through residual current and node voltage drop. When the target branch is a motor branch, it performs active bus discharge. It determines the discharge is completed based on the bus residual voltage attenuation and the access potential difference. It correlates the duty cycle growth slope with the remaining capacity coefficient. It completes soft start and determines stable power supply status through the access point voltage deviation and the target branch current change rate. Collaborative Degradation Control Module: Maps the target power limit of the motor branch to the torque limit, the target power limit of the valve group branch to the maximum operating frequency, and the target power limit of the parking branch to the operating permission condition. It performs differentiated collaborative control based on the vehicle's operating status and sends the power supply boundary back to the chassis main controller.

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