Control method for inhibiting low-voltage power supply disturbance in electromechanical brake release working condition

Abstract

The application discloses a kind of control methods for inhibiting electromechanical brake brake release working condition low voltage power supply disturbance, it is related to automobile electromechanical brake control technical field.The application establishes mechanical braking force in brake clamping stage, and collects multiple vehicle signals to monitor low voltage power supply working condition in pressure maintaining stage;Brake release piece release stage adopts duty ratio ramp gradual change drive, and dissipates motor counter drag induced potential through buffer filter bus and controllable discharge branch;Meanwhile, according to fixed time delay sequence, each wheel brake reset is completed step by step, and instantaneous electrical impact is dispersed.When detecting low voltage sensitive working condition, start exclusive adaptation logic optimization drive parameter, full open discharge branch.The application effectively inhibits low voltage power supply disturbance generated in brake release process, solves vehicle low voltage voltage fluctuation, load impact problem, improves vehicle low voltage power supply stability and brake system working reliability.

Description

Technical Field

[0001] This invention relates to the field of automotive electromechanical braking control technology, and in particular to a control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake. Background Technology

[0002] Electromechanical brakes (EMBs), as the core actuators of brake-by-wire systems in new energy vehicles, achieve the clamping and release of brake pads through the coordinated operation of a permanent magnet servo motor, a reduction mechanism, and a ball screw. In related technologies, during the EMB brake release phase, the brake disc's inertia drags the motor rotor in the opposite direction via the ball screw and reduction mechanism, causing the permanent magnet motor to rotate passively and generate an alternating induced electromotive force (EMF). This electrical disturbance is directly transmitted to the vehicle's 12V low-voltage power supply network. Specifically, traditional EMB control strategies only have an inverter drive function. When the brake is released, the controller reverses the power to drive the motor back to its initial position. The back EMF generated by the reverse drag has no suppression circuit, and the instantaneous surge current directly disturbs the low-voltage power supply.

[0003] However, existing technologies directly employ passive voltage regulation via generators, DC-DC modules, and batteries, without designing dedicated suppression logic for the pulse-like electrical disturbances generated by intermittent EMB braking release. This can lead to a momentary surge in the 12V bus voltage, causing electrical interference faults such as flashing of onboard instruments, excessive low-voltage ECU power supply ripple, and controller malfunctions. Furthermore, the simultaneous issuance of EMB braking release commands across all four wheels amplifies the low-voltage power supply disturbance due to the superimposed instantaneous electrical impact from multiple wheels. The lack of adaptive control logic and disturbance discharge circuits makes it unsuitable for the power supply immunity requirements under all driving conditions, severely impacting the stability of the vehicle's low-voltage power supply system. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] The main objective of this invention is to provide a control method for suppressing low-voltage power supply disturbances during the braking release operation of an electromechanical brake.

[0006] Another objective of this invention is to provide a control device for suppressing low-voltage power supply disturbances during the braking release operation of an electromechanical brake.

[0007] The third objective of this invention is to provide an electronic device.

[0008] To achieve the above objectives, a first aspect of the present invention provides a control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, comprising: S1 controls the motor to run in the forward direction during the braking clamping phase to establish mechanical braking force, and collects wheel speed signals, low-voltage bus voltage signals and vehicle low-voltage load signals in real time during the braking pressure holding phase to monitor the low-voltage power supply condition. S2, during the brake release and pad disengagement stage, the drive mode is switched by a duty cycle ramp-up method, so that the friction pads are disengaged from the brake disc, and the induced electromotive force generated by the brake disc reverse drag motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch. S3, upon receiving the brake release command, sequentially activates the electromechanical brakes of each wheel according to the preset delay sequence to perform brake release reset, thereby dispersing the instantaneous electrical impact on each wheel; S4, when a low-pressure sensitive operating condition trigger signal is detected, activates dedicated adaptation logic to optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect.

[0009] Optionally, the step of real-time acquisition of wheel speed signals, low-voltage bus voltage signals, and vehicle low-voltage load signals during the braking and pressure holding phase to monitor the low-voltage power supply condition includes: real-time interaction between the EMB ECU and the VCU and 12V power controller to acquire wheel speed signals, braking commands, 12V bus voltage, instantaneous low-voltage load power of the vehicle, ABS trigger signals, and vehicle start-up status signals to monitor the low-voltage power supply condition.

[0010] Optionally, the step of buffering and dissipating the induced electromotive force generated by the brake disc reverse drag motor through the buffer filter bus and the controllable discharge branch includes: feeding the induced electromotive force generated by the brake disc reverse drag motor into an independent buffer bus, buffering it through a thin-film filter capacitor connected in parallel to the buffer bus, and dissipating the excess impact energy locally through the MOS transistor and power discharge resistor in the controllable discharge branch.

[0011] Optionally, the step of sequentially activating the electromechanical brakes of each wheel to perform brake release reset according to a preset delay sequence includes: the left front electromechanical brake first performs brake release reset, the right front electromechanical brake activates brake release reset after a 20ms interval, the left rear electromechanical brake activates brake release reset after another 20ms interval, and finally the right rear electromechanical brake activates brake release reset.

[0012] Optionally, the low-pressure sensitive operating condition trigger signal includes an ABS trigger signal, a vehicle cold start signal, or a vehicle high-power load start signal.

[0013] Optionally, the controllable discharge branch includes a MOSFET and a power discharge resistor, and the excess surge energy is dissipated locally as heat energy through the power discharge resistor after the MOSFET is turned on.

[0014] Optionally, the step of sequentially activating the electromechanical brakes of each wheel to perform brake release reset according to a preset delay sequence further includes: after the left front electromechanical brake performs brake release reset, sequentially delaying for 20ms to activate the brake release reset of the right front, left rear, and right rear electromechanical brakes to disperse the instantaneous electrical impact on each wheel.

[0015] Optionally, the activation of the dedicated adaptation logic, optimization of brake release drive parameters and full opening of the discharge branch includes: adopting a low-speed smooth drive return mode, optimizing the duty cycle ramp gradual switching slope, and fully opening the controllable discharge branch to dissipate all the induced electromotive force generated by brake release reverse drag on-site.

[0016] To achieve the above objectives, a second aspect of the present invention provides a control device for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, comprising: The first module is used to control the motor to run in the forward direction during the braking clamping phase to establish mechanical braking force, and to collect wheel speed signals, low-voltage bus voltage signals and vehicle low-voltage load signals in real time during the braking pressure holding phase to monitor the low-voltage power supply condition. The second module is used to switch the drive mode by gradually changing the duty cycle during the brake release and pad disengagement stage, so that the friction pads are disengaged from the brake disc, and the induced electromotive force generated by the brake disc reverse drag motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch. The third module is used to activate the electromechanical brakes of each wheel in a preset delay sequence after receiving the brake release command to perform brake release reset, so as to disperse the instantaneous electrical impact of each wheel. The first module is used to activate dedicated adaptation logic when a low-pressure sensitive operating condition trigger signal is detected, optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect.

[0017] To achieve the above objectives, a third aspect of this application provides an electronic device, including a processor and a memory; wherein the processor runs a program corresponding to the executable program code stored in the memory to implement the method described in the first aspect.

[0018] The embodiments of the present invention have the following beneficial effects: by combining a control strategy that combines graded delayed energy release, ramp gradual drive and working condition adaptive discharge, the instantaneous electrical impact caused by the synchronous release of multiple brakes is effectively reduced, the reverse drag induced electromotive force is quickly dissipated, and the voltage fluctuation and power supply disturbance of the vehicle's low-voltage bus are significantly suppressed; it can be adapted to harsh low-voltage sensitive working conditions such as cold start, ABS triggering, and high-power load opening, and greatly improves the stability of the vehicle's low-voltage power supply, the smoothness of the electromechanical braking system and the safety of the vehicle operation. Attached Figure Description

[0019] The above-described and additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, in which: Figure 1 The flowchart illustrates a control method for suppressing low-voltage power supply disturbances during the braking release operation of an electromechanical brake, as provided in an embodiment of the present invention. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0022] The following describes, with reference to the accompanying drawings, a control method and apparatus for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, according to an embodiment of the present invention.

[0023] Example 1 Figure 1 This is a flowchart of a control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, according to an embodiment of the present invention.

[0024] like Figure 1 As shown, the control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake includes the following steps: S1 controls the motor to run in the forward direction during the braking clamping phase to establish mechanical braking force, and collects wheel speed signals, low-voltage bus voltage signals and vehicle low-voltage load signals in real time during the braking pressure holding phase to monitor the low-voltage power supply condition.

[0025] During the braking clamping phase, the motor is controlled to rotate forward to drive the brake actuator and generate mechanical braking force, thereby responding to the braking command and establishing the required braking effect. During this phase, the motor is in a controlled drive state, and its electrical behavior is unaffected by the low-voltage power supply system. During the braking pressure holding phase, various signals reflecting the vehicle's motion state and the operating condition of the low-voltage power supply system are continuously collected, including wheel speed signals representing wheel rotation speed, low-voltage bus voltage signals representing the voltage level of the low-voltage power supply network, and vehicle low-voltage load signals representing the power of the vehicle's electrical load. By monitoring these signals in real time, the current operating state of the low-voltage power supply system can be dynamically obtained, providing a predictive basis and parameter foundation for potential electrical disturbances that may occur during the subsequent braking release phase.

[0026] As one implementation method, during the braking clamping phase, the vehicle controller issues a braking request, and the electromechanical brake controller controls the power bridge inverter to output three-phase AC power to drive the motor to run in the forward direction. The lead screw moves forward to push the friction pads to fit against the brake disc to establish mechanical braking force. During the braking pressure holding phase, wheel speed, low-voltage bus voltage, and vehicle low-voltage load signals are continuously collected to monitor the low-voltage power supply condition in real time and pre-match the corresponding disturbance suppression control strategy.

[0027] Through the above steps, braking force can be reliably established during the braking clamping phase, and real-time perception and monitoring of the low-voltage power supply condition can be achieved during the braking pressure holding phase. This provides accurate status information and decision-making basis for disturbance suppression control in the subsequent braking release phase, effectively improving the stability and anti-disturbance capability of the low-voltage power supply system under full braking conditions.

[0028] S2, during the brake release and pad disengagement phase, uses a duty cycle ramp-up method to switch the drive mode, causing the friction pads to disengage from the brake disc, and buffering and dissipating the induced electromotive force generated by the brake disc reverse drag motor through the buffer filter bus and the controllable discharge branch.

[0029] During the brake release and pad disengagement phase, after the brake command is cancelled, the electromechanical brake needs to switch from the brake clamping state to the brake release and reset state. This switching process involves reversing the power supply to the drive motor to drive the friction pads away from the brake disc. To suppress the instantaneous inrush current caused by the sudden change in drive current during mode switching, this step uses a duty cycle ramp-up method to smoothly switch the drive mode. That is, the duty cycle of the drive signal gradually transitions from the current value to the target value according to a preset ramp, thereby avoiding a step change in the drive current and suppressing electrical shocks at the source. At the same time, after the friction pads disengage from the brake disc, the brake disc continues to rotate due to inertia, dragging the motor rotor in the opposite direction through the reduction mechanism, causing the permanent magnet motor to rotate passively and generate an alternating induced electromotive force. If this induced electromotive force is directly conducted to the low-voltage power supply system, it will cause voltage fluctuations and current surges. Therefore, this step introduces the induced electromotive force into a preset buffer filter bus, which is connected in parallel with a filter capacitor to absorb the high-frequency peak energy in the induced electromotive force and achieve the buffering of the instantaneous electromotive force. Furthermore, the excess electrical energy remaining after buffering is dissipated locally in the form of heat energy through a controllable discharge branch, thereby completely blocking the conduction path of the induced electromotive force to the low-voltage power supply system.

[0030] As one implementation method, after the friction pad disengages from the brake disc and leaves a preset gap, the drive PWM is gradually cut off according to the set ramp slope to achieve smooth switching of the drive mode; at the same time, the induced electromotive force is filtered by the buffer bus and then dissipated by a controllable discharge branch composed of power switching devices and discharge resistors to ensure the stability of the low-voltage bus voltage.

[0031] This step effectively suppresses the instantaneous inrush current and voltage fluctuations during the brake release disc disengagement stage through a dual mechanism of soft switching of drive mode and buffer discharge of induced electromotive force. It avoids the direct conduction of electrical disturbances to the low-voltage power supply system, thereby improving the stability of the vehicle's low-voltage power supply and the operational reliability of the vehicle's electrical appliances.

[0032] S3, upon receiving the brake release command, sequentially activates the electromechanical brakes of each wheel according to the preset delay sequence to perform brake release reset, thereby dispersing the instantaneous electrical impact on each wheel.

[0033] Upon receiving a brake release command, this method employs a timing control strategy to orderly schedule the electromechanical brakes of each wheel, thereby dispersing the instantaneous electrical shocks generated during brake release. Specifically, this method does not cause all wheel electromechanical brakes to perform brake release and reset operations simultaneously. Instead, based on a preset delay sequence, the brake release actions of each wheel are staggered on the time axis, thus dispersing the potentially synchronously superimposed instantaneous electrical shocks to different time points. This staggered timing effectively prevents the induced electromotive force and surge current generated by the reverse drag motors of each wheel from flowing into the low-voltage power supply system at the same moment during simultaneous brake release of multiple wheels, thereby eliminating the superposition effect of electrical disturbances and reducing the instantaneous fluctuation amplitude and current spike intensity of the low-voltage bus voltage.

[0034] As one implementation method, the electromechanical brakes of each wheel can be activated sequentially at fixed time intervals (e.g., 20 milliseconds) in the order of left front wheel, right front wheel, left rear wheel, and right rear wheel to perform brake release reset. This significantly suppresses electrical disturbances to the vehicle's low-voltage power supply system caused by simultaneous operation of multiple wheels while ensuring the complete realization of the brake release function.

[0035] By adopting the above-mentioned delayed sequential start brake release control strategy, this method can effectively disperse the instantaneous electrical impact of each wheel without changing the mechanical structure and basic braking performance of the electromechanical brake, and avoid the concentrated impact of the superposition of multiple wheel synchronous disturbances on the low-voltage power supply system, thereby improving the stability and anti-interference capability of the vehicle's low-voltage power supply network.

[0036] S4, when a low-pressure sensitive operating condition trigger signal is detected, activates dedicated adaptation logic to optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect.

[0037] When a trigger signal indicating a sensitive operating condition in the low-voltage power supply system is detected, this method activates a dedicated adaptation logic matched to that condition to dynamically optimize the braking release drive parameters of the electromechanical brake. Simultaneously, the controllable discharge branch is switched to a fully open state, thereby enhancing the suppression of low-voltage power supply disturbances. Specifically, this dedicated adaptation logic adaptively adjusts control parameters such as the drive rate, duty cycle switching slope, or return mode during the braking release process based on the detected sensitive operating condition type. This allows the electromechanical brake to operate more smoothly and with lower impact during the release return phase, reducing the amplitude of the induced electromotive force and the intensity of the inrush current generated by the brake disc's inertial reverse motor at the source. Simultaneously, by fully activating the controllable discharge branch, a low-impedance discharge path is provided for the instantaneous excess electromotive force generated during braking release, allowing it to be dissipated locally, thus completely blocking the transmission path of electrical disturbances to the low-voltage power supply system.

[0038] As one implementation, the low-voltage sensitive operating condition trigger signal may include, but is not limited to, vehicle cold start signal, anti-lock braking system trigger signal, or vehicle high-power load start signal. When such a signal is detected, the corresponding dedicated adaptation logic is triggered to provide targeted disturbance suppression protection under the most vulnerable operating conditions of the low-voltage power supply system.

[0039] Through the above-mentioned dedicated adaptive control for low-voltage sensitive operating conditions, this method can proactively enhance the ability to suppress electrical disturbances during the braking release of electromechanical brakes at critical moments when the vehicle's low-voltage power supply system faces significant fluctuation risks. This effectively avoids voltage oscillations or excessive ripple caused by the superposition of power supply disturbances and sensitive operating conditions, thereby significantly improving the stability and reliability of the vehicle's low-voltage power supply system under various extreme or special operating conditions and ensuring the normal operation of sensitive on-board electrical equipment.

[0040] Example 2 Based on the above embodiments, this embodiment provides a detailed description of the specific implementation of step S1 in the control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake: "Controlling the motor to run in the forward direction during the braking clamping stage to establish mechanical braking force, and collecting wheel speed signals, low-voltage bus voltage signals, and vehicle low-voltage load signals in real time during the braking pressure holding stage to monitor the low-voltage power supply condition."

[0041] In this embodiment, during the braking and pressure holding phase described in step S1, wheel speed signals, low-voltage bus voltage signals, and vehicle low-voltage load signals are collected in real time to monitor the low-voltage power supply condition. This is specifically achieved through the following method: The EMB ECU, as the core control unit, establishes a real-time data interaction link with the vehicle controller (VCU) and the 12V power controller via the controller area network bus. During the braking and pressure holding phase, the EMB ECU first obtains the wheel speed signals of each wheel from the wheel speed sensors. These signals represent the current wheel speed value in the form of pulse frequency. Simultaneously, the EMB ECU receives braking command signals issued by the VCU via the CAN bus. These commands include parameters such as brake pedal opening or braking torque demand, used to determine whether the braking state continues. In addition, the EMB ECU collects real-time sampled values ​​of the 12V bus voltage and instantaneous low-voltage load power data of the vehicle from the 12V power controller. The bus voltage is input in digital form through an analog-to-digital converter interface, while the load power is calculated based on the product of current detection and voltage within the power controller. The EMB ECU also simultaneously receives the ABS trigger signal from the ABS controller. This signal is a Boolean state variable used to indicate whether the ABS is active. Simultaneously, the EMB ECU obtains the vehicle start status signal from the VCU or Body Control Module (BCM), indicating whether the engine or powertrain has completed starting. These multi-source signals are conditioned and filtered within the EMB ECU, then comprehensively analyzed by the operating condition monitoring module. The module outputs a quantitative assessment of the current low-voltage power supply condition, including characteristic parameters such as bus voltage fluctuation amplitude, load rate, and whether it is under sensitive operating conditions. This provides input for matching adaptive disturbance suppression strategies in subsequent steps.

[0042] Through the real-time interaction and comprehensive monitoring of the above-mentioned multi-source signals, this embodiment can fully perceive the real-time status of the low-voltage power supply system, providing a precise data foundation for condition-adaptive disturbance suppression control, thereby significantly improving the pertinence and effectiveness of the control strategy, and ensuring that power supply disturbance risks can be accurately identified and control parameters can be adapted in advance under different driving conditions.

[0043] Example 3 Based on the above embodiments, this embodiment provides a detailed description of the specific implementation of step S2 in the control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake: "In the brake release pad disengagement stage, the drive mode is switched by a gradual change in duty cycle ramp, so that the friction pads disengage from the brake disc, and the induced electromotive force generated by the brake disc reverse drag motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch."

[0044] In this embodiment, the specific implementation of buffering and dissipating the induced electromotive force generated by the brake disc reverse-dragging motor in step S2 through a buffer filter bus and a controllable discharge branch is as follows: When the braking command is cancelled, the controller drives the motor to rotate in the reverse direction, causing the friction pads to disengage from the brake disc. The brake disc continues to rotate under inertia, and through the ball screw and reduction mechanism, it drags the rotor of the permanent magnet servo motor of the electromechanical brake in the reverse direction, causing the permanent magnet motor to rotate passively and generate an alternating induced electromotive force. This induced electromotive force is used as input and is first fed into an independently set buffer bus. A thin-film filter capacitor is connected in parallel to this buffer bus. The thin-film filter capacitor is used to buffer and absorb the instantaneous voltage spikes of the induced electromotive force, smoothing the high-amplitude pulse potential into a relatively smooth energy fluctuation, thereby suppressing sudden voltage changes. After the initial buffering by the thin-film filter capacitor, if the energy of the induced electromotive force exceeds the buffering capacity of the capacitor, the excess impact energy is used as input and guided to the controllable discharge branch connected in parallel with the buffer bus. The controllable discharge branch includes a metal-oxide-semiconductor field-effect transistor (MOSFET) and a power discharge resistor connected in series. In one possible implementation, when the buffer bus voltage exceeds a preset safety threshold, the controller applies a conduction voltage to the gate of the MOSFET, causing it to enter a conducting state, thereby guiding the excess surge energy to the power discharge resistor. The power discharge resistor converts the received energy into heat energy, which is dissipated locally on the resistive element, thus completely eliminating the impact of this portion of energy on the low-voltage power supply system. Through the above-described series processing flow of "buffer bus input - thin-film capacitor buffer - controllable branch discharge," the complete absorption and dissipation of the induced electromotive force generated by the brake disc reverse drag motor is achieved. The final output result is that the low-voltage bus side no longer suffers from instantaneous voltage surges and surge current backflow, ensuring the voltage stability of the vehicle's low-voltage power supply network.

[0045] This specific implementation method, by constructing an independent buffer filter and controllable discharge hardware topology, achieves precise absorption and on-site heat energy conversion of the induced electromotive force of braking release, completely cutting off the transmission path of electrical disturbances to the low-voltage power supply system from a physical level, and significantly improving the anti-interference capability and reliability of the vehicle's low-voltage power supply network.

[0046] Example 4 Based on the above embodiments, this embodiment provides a detailed description of the specific implementation of step S3 in the control method for suppressing low-voltage power supply disturbances during the braking release of electromechanical brakes: "After receiving the brake release command, the electromechanical brakes of each wheel are sequentially activated according to a preset delay sequence to perform brake release reset, so as to disperse the instantaneous electrical impact of each wheel."

[0047] In this embodiment, step S3, which involves sequentially activating the electromechanical brakes of each wheel according to a preset delay sequence to perform brake release reset, is specifically implemented through a four-wheel staggered peak-time control timing sequence. When the vehicle controller (VCU) issues a brake release command, the electromechanical brake electronic control unit (EMB ECU) receives the command as an input signal and immediately activates the preset delay control logic. First, the left front electromechanical brake is immediately triggered to perform a brake release reset operation. Its drive circuit begins to operate, controlling the motor to rotate in the reverse direction to drive the lead screw backward, causing the friction pads to disengage from the brake disc with a gap of 0.2 to 0.4 mm. Simultaneously, the induced electromotive force generated by the brake disc inertia-driven reverse-draft motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch. After the left front electromechanical brake initiates the brake release reset, the timer inside the EMB ECU begins counting. After a fixed delay interval of 20 milliseconds, the EMB ECU outputs a start signal to the right front electromechanical brake, causing it to begin performing the brake release reset operation, with the same action flow as the left front wheel. Subsequently, after a 20-millisecond delay (40 milliseconds after the left front wheel starts), the EMB ECU outputs a start signal to the left rear electromechanical brake, initiating brake release reset. Finally, after another 20-millisecond delay (60 milliseconds after the left front wheel starts), the EMB ECU outputs a start signal to the right rear electromechanical brake, initiating brake release reset. This staggered start method, with sequential 20-millisecond delays, effectively disperses the instantaneous electrical shocks generated by the electromechanical brakes of all four wheels during brake release reset along the time axis. This avoids the superposition effect of the back drag induced electromotive force and the surge current during simultaneous four-wheel brake release, thus dispersing the independent electrical disturbances of each wheel to different time points and significantly reducing the instantaneous impact on the vehicle's low-voltage power supply system.

[0048] This specific implementation method uses four-wheel staggered peak-time braking release control to disperse the instantaneous electrical impact generated by multiple wheels synchronously to different time points, effectively eliminating the disturbance superposition effect, significantly reducing the instantaneous impact amplitude of the low-voltage power supply system, and improving the stability of the vehicle's low-voltage power supply.

[0049] Example 5 Based on the above embodiments, this embodiment provides a detailed description of the specific implementation of step S4 in the control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake: "When a low-voltage sensitive condition trigger signal is detected, a dedicated adaptation logic is activated to optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect."

[0050] In this embodiment, when the vehicle enters a low-pressure sensitive operating condition, the EMB ECU will detect and identify the corresponding trigger signals in real time. Specifically, the low-pressure sensitive operating condition trigger signals include the ABS trigger signal, the vehicle cold start signal, or the vehicle high-power load activation signal. The ABS trigger signal is generated by the vehicle controller (VCU) when it detects an emergency braking condition and sent to the EMB ECU; the vehicle cold start signal is generated by the power management system when it detects the vehicle starting state; and the vehicle high-power load activation signal is generated by the body controller (BCM) when it detects the activation of high-power loads such as the air conditioning compressor or high beams. Upon receiving any of the above trigger signals, the EMB ECU immediately activates dedicated adaptation logic to optimize the brake release drive parameters and fully open the discharge branch. In one possible implementation, this dedicated adaptation logic specifically includes: the EMB ECU first switches the drive mode to a low-speed smooth drive return mode, that is, controlling the motor to reverse drive at a speed lower than the normal operating condition, causing the lead screw to slowly retract, thereby reducing the amplitude of the induced electromotive force generated by the brake disc reverse drag motor. Meanwhile, the EMB ECU optimizes the duty cycle ramp-up switching slope, extending the PWM duty cycle switching time between the brake clamping mode and the brake release reset mode to over 50 milliseconds to further suppress the instantaneous inrush current generated during mode switching. Furthermore, the EMB ECU sends a full-on command to the power MOSFET in the controllable discharge branch, ensuring the power discharge resistor is fully connected to the buffer bus, thereby dissipating all the induced electromotive force generated by the brake release reverse drag into heat energy on-site. Through these measures, all electrical disturbances generated during brake release are blocked at the motor side, completely eliminating the possibility of inrush current flowing back into the 12V low-voltage power supply system, ensuring the stable operation of on-board electrical equipment under sensitive conditions.

[0051] This specific implementation achieves refined optimization of brake release drive parameters and full opening control of the discharge branch through dedicated adaptation logic for low-voltage sensitive operating conditions. As a result, in critical operating conditions such as ABS triggering, vehicle cold start, or high-power load activation, it completely eliminates the impact of electrical disturbances on the low-voltage power supply system from the source, significantly improving the stability of the vehicle's low-voltage power supply and the operational reliability of the vehicle's electrical appliances.

[0052] Example 6 In this embodiment, a complete implementation of a control method for suppressing low-voltage power supply disturbances during the braking release of an electromechanical brake (EMB) will be described in detail, covering the hardware topology architecture, data acquisition and interaction, software hierarchical control strategy, and execution flow under various specific operating conditions, so as to fully disclose all the technical contents recorded in the technical disclosure.

[0053] The hardware topology used in this embodiment employs a three-level anti-disturbance architecture. The first level is a buffer filter bus. The EMB three-phase permanent magnet motor is matched with a dedicated drive circuit. During brake release, the brake disc's inertia drags the motor rotor in the opposite direction via a ball screw and reduction mechanism, causing the alternating induced electromotive force generated by the passive rotation of the permanent magnet motor to flow into this independent buffer bus. A thin-film filter capacitor is connected in parallel on the buffer bus to buffer instantaneous potential spikes. The second level is an electrical isolation module, located between the EMB motor drive control circuit and the vehicle's 12V low-voltage side, achieving electrical isolation between the motor side and the low-voltage side, blocking the direct transmission path of electrical disturbances. The third level is a controllable discharge branch, connected to the buffer bus and composed of a MOSFET and a power discharge resistor connected in series, used to dissipate the remaining excess impact energy as heat on-site. Furthermore, high-frequency filter capacitors are added across the 12V battery terminals to assist in smoothing small electrical ripples, collaboratively constructing a multi-layered anti-disturbance system.

[0054] In terms of data acquisition and operating condition monitoring, the EMB ECU interacts in real time with the vehicle control unit (VCU) and the 12V power controller. The acquired signals include wheel speed signals, braking commands, 12V bus voltage, instantaneous low-voltage load power of the vehicle, ABS trigger signals, and vehicle start-up status signals. These signals provide data support for subsequent adaptive disturbance rejection control, enabling the system to monitor the low-voltage power supply status in real time and dynamically match appropriate control strategies accordingly.

[0055] During the braking clamping phase, the VCU issues a braking request, and the EMB ECU controls the power bridge inverter to output three-phase AC power, driving the motor to rotate in the forward direction. This, through the ball screw, pushes the friction pads to engage with the brake disc, establishing mechanical braking force and fulfilling the vehicle's braking requirements. During this phase, because the motor is in an active driving state, no electrical disturbances are generated. After entering the brake pressure holding phase, the system continuously collects signals such as wheel speed, 12V bus voltage, vehicle low-voltage load, and ABS status, monitoring the low-voltage power supply condition in real time to prepare for the pre-matching of subsequent disturbance suppression control strategies.

[0056] When the braking command is cancelled and the brake release and disc disengagement phase begins, the controller first reverses the lead screw with a small current to disengage the friction pads from the brake disc, leaving a gap of 0.2 to 0.4 mm. During this process, the drive mode switching adopts duty cycle ramp-based soft-switching control, setting a soft-start or soft-stop slope of 10 to 50 milliseconds to achieve a smooth switch from the brake clamping mode to the brake release and reset mode, thereby suppressing the inrush current generated during mode switching. The induced electromotive force generated by the brake disc inertia-driven EMB motor is buffered by the thin-film filter capacitor on the buffer filter bus, effectively suppressing the instantaneous potential spike; the remaining excess impact energy after buffering is dissipated locally as heat through the MOSFET in the controllable discharge branch and the power discharge resistor, completely blocking electrical disturbances from entering the low-voltage power supply system.

[0057] Upon receiving the vehicle's brake release command, the system executes staggered, time-sharing brake release control for all four wheels. Specifically, the left front electromechanical brake first performs a brake release reset, followed by the right front electromechanical brake after a 20-millisecond interval, then the left rear electromechanical brake after another 20-millisecond interval, and finally the right rear electromechanical brake. This sequentially delayed control sequence disperses the instantaneous electrical impact on all four wheels, completely eliminating the superposition effect of disturbances caused by simultaneous brake releases from multiple wheels. After each wheel's brake release reset is completed, the lead screw returns to its mechanical limit position, the motor stops reverse drag, the controller switches back to standby drive mode, and a single brake release operation is completed, with no low-voltage power supply disturbance transmission throughout the process.

[0058] For low-voltage sensitive operating conditions, this embodiment sets up dedicated adaptation logic. This logic is triggered when the system detects an ABS trigger signal, a vehicle cold start signal, or a high-power load such as the vehicle's air conditioning or high beams being turned on. In this mode, the EMB adopts a low-speed smooth drive return mode, further optimizing the duty cycle ramp-up switching slope to maximize the suppression of instantaneous inrush current; at the same time, the controllable discharge branch is fully opened, dissipating all the induced electromotive force generated by brake release back drag on-site, completely blocking electrical disturbances from entering the low-voltage power supply system, and ensuring the stable operation of vehicle electrical appliances under sensitive operating conditions.

[0059] When the vehicle's low-voltage system is in a high-load steady-state operating condition, the EMB ECU monitors the 12V bus voltage fluctuation threshold in real time and dynamically fine-tunes the release drive rate and PWM switching time accordingly. In conjunction with the buffer filter topology, it smooths out electrical ripple in real time and continuously suppresses power disturbances caused by braking release conditions, thereby adapting to the high-load operation scenario of the vehicle.

[0060] In summary, this embodiment, through a three-level hardware topology of buffer filter bus, electrical isolation and controllable discharge branch, combined with condition-adaptive disturbance suppression, four-wheel off-peak time-sharing braking release, PWM soft switching control and multi-condition intelligent adaptation logic, effectively suppresses electrical disturbances of EMB braking release under all operating conditions without altering the existing EMB body mechanical structure. This significantly improves the stability of the vehicle's low-voltage power supply system and the operational reliability of on-board electrical appliances.

[0061] Example 7 This invention also provides a control device for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, comprising: The first module is used to control the motor to run in the forward direction during the braking clamping phase to establish mechanical braking force, and to collect wheel speed signals, low-voltage bus voltage signals and vehicle low-voltage load signals in real time during the braking pressure holding phase to monitor the low-voltage power supply condition. The second module is used to switch the drive mode by gradually changing the duty cycle during the brake release and pad disengagement stage, so that the friction pads are disengaged from the brake disc, and the induced electromotive force generated by the brake disc reverse drag motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch. The third module is used to activate the electromechanical brakes of each wheel in a preset delay sequence after receiving the brake release command to perform brake release reset, so as to disperse the instantaneous electrical impact of each wheel. The first module is used to activate dedicated adaptation logic when a low-pressure sensitive operating condition trigger signal is detected, optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect.

[0062] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0063] Example 8 To implement the methods of the above embodiments, the present invention also provides an electronic device, which includes a memory and a processor; wherein the processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the various steps of the methods described above.

[0064] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0065] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0066] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A control method for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, characterized in that, Includes the following steps: S1 controls the motor to run in the forward direction during the braking clamping phase to establish mechanical braking force, and collects wheel speed signals, low-voltage bus voltage signals and vehicle low-voltage load signals in real time during the braking pressure holding phase to monitor the low-voltage power supply condition. S2, during the brake release and pad disengagement stage, the drive mode is switched by a duty cycle ramp-up method, so that the friction pads are disengaged from the brake disc, and the induced electromotive force generated by the brake disc reverse drag motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch. S3, upon receiving the brake release command, sequentially activates the electromechanical brakes of each wheel according to the preset delay sequence to perform brake release reset, thereby dispersing the instantaneous electrical impact on each wheel; S4, when a low-pressure sensitive operating condition trigger signal is detected, activates dedicated adaptation logic to optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect.

2. The method as described in claim 1, characterized in that, The method of real-time acquisition of wheel speed signals, low-voltage bus voltage signals, and vehicle low-voltage load signals during the braking and pressure holding phase to monitor the low-voltage power supply condition includes: real-time interaction between the EMB ECU and the VCU and 12V power controller to acquire wheel speed signals, braking commands, 12V bus voltage, instantaneous low-voltage load power of the vehicle, ABS trigger signals, and vehicle start status signals to monitor the low-voltage power supply condition.

3. The method as described in claim 1, characterized in that, The process of buffering and dissipating the induced electromotive force generated by the brake disc reverse drag motor through the buffer filter bus and the controllable discharge branch includes: feeding the induced electromotive force generated by the brake disc reverse drag motor into an independent buffer bus, buffering it through a thin-film filter capacitor connected in parallel to the buffer bus, and dissipating the excess impact energy locally through the MOS transistor and power discharge resistor in the controllable discharge branch.

4. The method as described in claim 1, characterized in that, The step of sequentially activating the electromechanical brakes of each wheel to perform brake release and reset according to a preset delay sequence includes: the left front electromechanical brake first performs brake release and reset, the right front electromechanical brake activates brake release and reset after a 20ms interval, the left rear electromechanical brake activates brake release and reset after another 20ms interval, and finally the right rear electromechanical brake activates brake release and reset.

5. The method as described in claim 1, characterized in that, The low-pressure sensitive operating condition trigger signals include ABS trigger signals, vehicle cold start signals, or vehicle high-power load start signals.

6. The method as described in claim 3, characterized in that, The controllable discharge branch includes a MOSFET and a power discharge resistor. The excess surge energy is dissipated locally as heat energy after the MOSFET is turned on and the power discharge resistor is used for on-site conduction.

7. The method as described in claim 4, characterized in that, The step of sequentially activating the electromechanical brakes of each wheel according to a preset delay sequence to perform brake release reset also includes: after the left front electromechanical brake performs brake release reset, sequentially delaying for 20ms to activate the brake release reset of the right front, left rear, and right rear electromechanical brakes to disperse the instantaneous electrical impact on each wheel.

8. The method as described in claim 5, characterized in that, The activation of the dedicated adaptation logic, optimization of brake release drive parameters and full opening of the discharge branch include: adopting a low-speed smooth drive return mode, optimizing the duty cycle ramp gradual switching slope, and fully opening the controllable discharge branch to dissipate all the induced electromotive force generated by brake release reverse drag on-site.

9. A control device for suppressing low-voltage power supply disturbances during the braking release condition of an electromechanical brake, characterized in that, include: The first module is used to control the motor to run in the forward direction during the braking clamping phase to establish mechanical braking force, and to collect wheel speed signals, low-voltage bus voltage signals and vehicle low-voltage load signals in real time during the braking pressure holding phase to monitor the low-voltage power supply condition. The second module is used to switch the drive mode by gradually changing the duty cycle during the brake release and pad disengagement stage, so that the friction pads are disengaged from the brake disc, and the induced electromotive force generated by the brake disc reverse drag motor is buffered and dissipated locally through the buffer filter bus and the controllable discharge branch. The third module is used to activate the electromechanical brakes of each wheel in a preset delay sequence after receiving the brake release command to perform brake release reset, so as to disperse the instantaneous electrical impact of each wheel. The first module is used to activate dedicated adaptation logic when a low-pressure sensitive operating condition trigger signal is detected, optimize the braking release drive parameters and fully open the discharge branch to enhance the disturbance suppression effect.

10. An electronic device, characterized in that, Including processor and memory; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the method as described in any one of claims 1-8.

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