An electric vehicle wiper motor noise reduction method, system, device and medium

Abstract

This application discloses a method, system, device, and medium for noise reduction of electric vehicle wiper motors, belonging to the field of automotive noise reduction technology. The noise reduction method for electric vehicle wiper motors includes the following steps: real-time acquisition of drive motor speed and vibration signals; dynamic adjustment of the wiper motor PWM frequency to synchronize with the drive motor's fundamental frequency; and control of the vibration phase difference between the two to be stable within the range of 170°-190°. The method actively cancels 5-10kHz high-frequency noise using the principle of anti-phase acoustic interference, achieving a measured noise reduction of over 15dB. Simultaneously, a power-sharing design is used to achieve wiper braking energy feedback, improving overall energy efficiency by 10%-15%. This disclosure requires no additional sound insulation materials, has strong adaptability, and is particularly suitable for suppressing high-frequency howling in new energy vehicles.

Description

Technical Field

[0001] This application belongs to the field of automotive noise reduction technology, and in particular relates to a method, system, device and medium for noise reduction of electric vehicle wiper motor. Background Technology

[0002] With the rapid development of electric vehicles, their core advantage of low noise has ironically revealed new acoustic challenges. Unlike traditional gasoline vehicles, the electromagnetic whine (5-10kHz) generated by the drive motor of an electric vehicle at high speeds partially overlaps with the mechanical vibration noise of the windshield wipers (2-8kHz), resulting in a superposition of noise peaks inside the vehicle, forming a sharp "electronic buzzing effect." Studies have shown that at vehicle speeds of 60km / h, the superimposed noise is 6-10dB(A) higher than that of a single noise, significantly impacting driving comfort. Existing solutions have three major limitations: 1. Inefficient physical sound insulation: Traditional sound insulation cotton has an attenuation rate of less than 30% for high-frequency sound waves >3kHz, and it also increases vehicle weight; 2. Independent control defect: The drive motor and wiper motor belong to different ECU units, resulting in: Increased electromagnetic interference: The dual-system PWM carriers are randomly distributed, and the EMC radiation exceedance rate in the 3-10kHz frequency band reaches 37%. Energy redundancy: Independent power supply modules cause 12-15% energy loss; 3. Dynamic response hysteresis: Existing active noise cancellation solutions have a system delay of 20ms or less, resulting in a cancellation efficiency of less than 40% for transient high-frequency noise.

[0003] Although some technologies attempt to disperse noise energy through frequency conversion or cancel it out with reverse sound waves, none of them have resolved the contradiction between dual-system coordinated control and energy efficiency optimization.

[0004] Therefore, it is necessary to provide a new method, system, device, and medium for noise reduction of electric vehicle wiper motors to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this disclosure is to provide a method, system, device, and medium for noise reduction of electric vehicle windshield wiper motors in order to solve the above-mentioned problems.

[0006] This disclosure achieves the above objectives through the following technical solutions: A method for reducing noise in an electric vehicle windshield wiper motor includes the following steps: Calculate the base frequency of the drive motor in an electric vehicle; The PWM frequency of the wiper motor is dynamically adjusted to be synchronized with the base frequency of the drive motor; The vibration phase difference between the drive motor and the wiper motor is detected, and the PWM start time of the wiper motor is updated based on the vibration phase difference to stabilize the phase difference within a preset range. Noise is canceled by the principle of anti-phase interference of sound waves. Based on the dynamic matching amplitude of the sound pressure level, an LC resonant bridge is designed to realize the braking energy recovery of the wiper motor.

[0007] As a further optimization of this disclosure, dynamically adjusting the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor includes: The base frequency of the drive motor is set as the target frequency, and the PWM frequency of the wiper motor is adjusted by a fuzzy PID algorithm so that the error between the PWM frequency of the wiper motor and the target frequency is within a preset range.

[0008] As a further optimization of this disclosure, detecting the vibration phase difference between the drive motor and the wiper motor, and updating the PWM start time of the wiper motor based on the vibration phase difference to stabilize the phase difference within a preset range includes: The vibration phase difference between the drive motor and the wiper motor is detected by a cross-correlation algorithm; The delay time is calculated and the digital delay line is adjusted based on the vibration phase difference and the fundamental frequency; The PWM start time of the wiper motor is updated based on the delay time to stabilize the phase difference within a preset range.

[0009] As a further optimization of this disclosure, an LC resonant bridge is designed to realize the regenerative braking energy recovery of the wiper motor based on the dynamic matching amplitude of the sound pressure level, including: Based on the vibration amplitude of the drive motor, the sound pressure level is dynamically matched to the amplitude to adjust the power of the wiper motor; during the wiper return stroke, the designed LC resonant bridge recovers electrical energy to realize the recovery of braking energy of the wiper motor.

[0010] A noise reduction system for an electric vehicle wiper motor, comprising: The base frequency calculation module is used to calculate the base frequency of the drive motor of an electric vehicle. A PWM frequency adjustment module is used to dynamically adjust the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor; The phase difference adjustment module is used to detect the vibration phase difference between the drive motor and the wiper motor, update the PWM start time of the wiper motor based on the vibration phase difference, stabilize the phase difference within a preset range, and cancel noise through the principle of anti-phase interference of sound waves. The energy recovery module is used to dynamically match the amplitude according to the sound pressure level and design an LC resonant bridge to realize the braking energy recovery of the wiper motor.

[0011] As a further optimization of this disclosure, the PWM frequency adjustment module dynamically adjusts the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor, including: The base frequency of the drive motor is set as the target frequency, and the PWM frequency of the wiper motor is adjusted by a fuzzy PID algorithm so that the error between the PWM frequency of the wiper motor and the target frequency is within a preset range.

[0012] As a further optimization of this disclosure, the phase difference adjustment module detects the vibration phase difference between the drive motor and the wiper motor, and updates the PWM start time of the wiper motor based on the vibration phase difference to stabilize the phase difference within a preset range, including: The vibration phase difference between the drive motor and the wiper motor is detected by a cross-correlation algorithm; The delay time is calculated and the digital delay line is adjusted based on the vibration phase difference and the fundamental frequency; The PWM start time of the wiper motor is updated based on the delay time to stabilize the phase difference within a preset range.

[0013] As a further optimization of this disclosure, the energy recovery module dynamically matches the amplitude according to the sound pressure level and designs an LC resonant bridge to realize the recovery of braking energy from the wiper motor, including: Based on the vibration amplitude of the drive motor, the sound pressure level is dynamically matched to the amplitude to adjust the power of the wiper motor; during the wiper return stroke, the designed LC resonant bridge recovers electrical energy to realize the braking energy recovery of the wiper motor.

[0014] An electronic device includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; The processor is used to execute the program stored in the memory to implement the noise reduction method for the electric vehicle wiper motor.

[0015] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the electric vehicle windshield wiper motor noise reduction method.

[0016] The beneficial effects of this disclosure are as follows: The disclosed solution utilizes the principle of antiphase interference of sound waves to actively cancel high-frequency noise of 5-10kHz, with a measured noise reduction of over 15dB. At the same time, it achieves windshield wiper braking energy feedback through a power sharing design, improving overall energy efficiency by 10%-15%. It requires no additional sound insulation materials, has strong adaptability, and is especially suitable for suppressing high-frequency howling in new energy vehicles. It breaks through the limitations of traditional sound insulation materials and provides a cost-effective electromechanical synergistic solution for high-frequency noise control in electric vehicles. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a method in an embodiment of this disclosure; Figure 2 This is a system structure block diagram of an embodiment of this disclosure; Figure 3 This is a block diagram of the device structure in an embodiment of this disclosure. Detailed Implementation

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

[0020] like Figure 1 As shown, a method for reducing noise in an electric vehicle wiper motor includes the following steps: S1. Calculate the base frequency of the electric vehicle's drive motor, specifically including: The drive motor speed (n=6000rpm) is read via the CAN bus, and the base frequency is calculated based on the motor speed formula.

[0021] The main controller performs FFT analysis on the current harmonics to extract the main frequency amplitude (Ad=0.15g).

[0022] The main controller is an Infineon TC387 dual-core MCU with an integrated hardware FFT acceleration module (0.8ms calculation cycle); the drive motor is a permanent magnet synchronous motor (PMSM) with a peak power of 120kW, a pole pair count of p=8, and a rated speed of 7500rpm, equipped with: Vibration sensor: MEMS accelerometer (frequency range 5-20kHz, sensitivity 100mV / g); Current sampling module: Hall effect sensor (bandwidth 1MHz, accuracy ±0.5%).

[0023] S2. Dynamically adjust the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor, specifically including: Set the base frequency of the drive motor to the target frequency, and adjust the PWM frequency of the wiper motor using a fuzzy PID algorithm so that the error between the PWM frequency of the wiper motor and the target frequency is within a preset range: set the target frequency (fw=800Hz), and adjust the PWM duty cycle to 42.5% (corresponding to 3500rpm). A fuzzy PID algorithm (Kp=0.8, Ki=0.05, Kd=0.1) was used to control the frequency tracking error within ±30Hz.

[0024] The wiper motor uses a brushless DC motor (BLDC) with a rated voltage of 12V and a reduction ratio of 18:1. Adjustable PWM driver: switching frequency 100kHz, duty cycle resolution 0.1%; Photoelectric encoder: 1024 lines, phase detection accuracy ±0.1°.

[0025] S3. Detect the vibration phase difference between the drive motor and the wiper motor, update the PWM start time of the wiper motor based on the vibration phase difference, stabilize the phase difference within a preset range, and cancel noise through the principle of acoustic wave anti-phase interference, specifically including: The current phase difference (Δφ=150°) is measured using a cross-correlation algorithm; Calculate the delay time and adjust the digital delay line:

[0026] Update the wiper motor PWM start time to stabilize the phase difference at 180°± 3°.

[0027] S4. Based on the dynamic matching amplitude of the sound pressure level, design an LC resonant bridge to realize the braking energy recovery of the wiper motor, specifically including: Based on the vibration amplitude of the drive motor Ad=0.15g, adjust the wiper motor power to Pw=18W (original power 25W). During the windshield wiper return stroke, electrical energy is recovered through the LC resonant bridge, with a measured feedback efficiency of 83% (0.12 kWh recovered per hour).

[0028] Among them, the LC resonant bridge: Inductance L=50μH (iron-silicon-aluminum magnetic core, Q value≥80); Capacitor C = 0.1μF (C0G ceramic material, tolerance ±5%); The resonant frequency (fc=7.1kHz) covers the 5-10kHz main noise frequency band of the drive motor.

[0029] Noise reduction effect:

[0030] Through the above tests, the overall system efficiency increased from 85% to 93%, and the power consumption of the wipers decreased by 28%.

[0031] like Figure 2 As shown, embodiments of this disclosure provide a noise reduction system for an electric vehicle wiper motor, including: The base frequency calculation module is used to calculate the base frequency of the drive motor of an electric vehicle. A PWM frequency adjustment module is used to dynamically adjust the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor; The phase difference adjustment module is used to detect the vibration phase difference between the drive motor and the wiper motor, update the PWM start time of the wiper motor based on the vibration phase difference, stabilize the phase difference within a preset range, and cancel noise through the principle of anti-phase interference of sound waves. The energy recovery module is used to dynamically match the amplitude according to the sound pressure level and design an LC resonant bridge to realize the braking energy recovery of the wiper motor.

[0032] The implementation process of the functions and roles of each module in the above system is detailed in the implementation process of the corresponding steps in the above method, and will not be repeated here.

[0033] For the system embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The system embodiments described above are merely illustrative. The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this disclosure according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0034] See Figure 3 The electronic device provided in the embodiments of this disclosure includes a processor 1110, a communication interface 1120, a memory 1130 and a communication bus 1140, wherein the processor 1110, the communication interface 1120 and the memory 1130 communicate with each other through the communication bus 1140. Memory 1130 is used to store computer programs; The processor 1110, when executing the program stored in the memory 1130, implements the above-described method for reducing noise in the windshield wiper motor of an electric vehicle.

[0035] The aforementioned communication bus 1140 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus 1140 can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, it is represented by only one thick line in the figure, but this does not indicate that there is only one bus or one type of bus.

[0036] The communication interface 1120 is used for communication between the above-mentioned electronic device and other devices.

[0037] The memory 1130 may include random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Optionally, the memory 1130 may also be at least one storage device located remotely from the aforementioned processor 1110.

[0038] Embodiments of this disclosure also provide a computer-readable storage medium. The computer-readable storage medium stores a computer program that, when executed by a processor, implements the electric vehicle windshield wiper motor noise reduction method described above.

[0039] The embodiments described above are merely examples of several implementations of this disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent disclosure. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this disclosure, and these modifications and improvements all fall within the protection scope of this disclosure.

Claims

1. A method for noise reduction of an electric vehicle windshield wiper motor, characterized in that, Includes the following steps: Calculate the base frequency of the drive motor in an electric vehicle; The PWM frequency of the wiper motor is dynamically adjusted to be synchronized with the base frequency of the drive motor; The vibration phase difference between the drive motor and the wiper motor is detected, and the PWM start time of the wiper motor is updated based on the vibration phase difference to stabilize the phase difference within a preset range. Noise is canceled by the principle of anti-phase interference of sound waves. Based on the dynamic matching amplitude of the sound pressure level, an LC resonant bridge is designed to realize the braking energy recovery of the wiper motor.

2. The electric vehicle wiper motor noise reduction method of claim 1, wherein, Dynamically adjusting the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor includes: The base frequency of the drive motor is set as the target frequency, and the PWM frequency of the wiper motor is adjusted by a fuzzy PID algorithm so that the error between the PWM frequency of the wiper motor and the target frequency is within a preset range.

3. The electric vehicle wiper motor noise reduction method of claim 1, wherein, Detecting the vibration phase difference between the drive motor and the wiper motor, and updating the PWM start time of the wiper motor based on the vibration phase difference to stabilize the phase difference within a preset range, including: The vibration phase difference between the drive motor and the wiper motor is detected by a cross-correlation algorithm; The delay time is calculated and the digital delay line is adjusted based on the vibration phase difference and the fundamental frequency; The PWM start time of the wiper motor is updated based on the delay time to stabilize the phase difference within a preset range.

4. The electric vehicle wiper motor noise reduction method of claim 1, wherein, Based on the dynamic matching amplitude of the sound pressure level, an LC resonant bridge is designed to realize the regenerative braking energy recovery of the wiper motor, including: Based on the vibration amplitude of the drive motor, the sound pressure level is dynamically matched to the amplitude to adjust the power of the wiper motor; during the wiper return stroke, the designed LC resonant bridge recovers electrical energy to realize the recovery of braking energy of the wiper motor.

5. An electric vehicle wiper motor noise reduction system, characterized by, include: The base frequency calculation module is used to calculate the base frequency of the drive motor of an electric vehicle. A PWM frequency adjustment module is used to dynamically adjust the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor; The phase difference adjustment module is used to detect the vibration phase difference between the drive motor and the wiper motor, update the PWM start time of the wiper motor based on the vibration phase difference, stabilize the phase difference within a preset range, and cancel noise through the principle of anti-phase interference of sound waves. The energy recovery module is used to dynamically match the amplitude according to the sound pressure level and design an LC resonant bridge to realize the braking energy recovery of the wiper motor.

6. The electric vehicle wiper motor noise reduction system of claim 5, wherein, The PWM frequency adjustment module dynamically adjusts the PWM frequency of the wiper motor to synchronize with the base frequency of the drive motor, including: The base frequency of the drive motor is set as the target frequency, and the PWM frequency of the wiper motor is adjusted by a fuzzy PID algorithm so that the error between the PWM frequency of the wiper motor and the target frequency is within a preset range.

7. The electric vehicle wiper motor noise reduction system according to claim 5, characterized in that, The phase difference adjustment module detects the vibration phase difference between the drive motor and the wiper motor, and updates the PWM start time of the wiper motor based on the vibration phase difference to stabilize the phase difference within a preset range, including: The vibration phase difference between the drive motor and the wiper motor is detected by a cross-correlation algorithm; The delay time is calculated and the digital delay line is adjusted based on the vibration phase difference and the fundamental frequency; The PWM start time of the wiper motor is updated based on the delay time to stabilize the phase difference within a preset range.

8. The electric vehicle wiper motor noise reduction system of claim 5, wherein, The energy recovery module dynamically matches the amplitude based on the sound pressure level and designs an LC resonant bridge to realize the recovery of braking energy from the wiper motor, including: Based on the vibration amplitude of the drive motor, the sound pressure level is dynamically matched to the amplitude to adjust the power of the wiper motor; during the wiper return stroke, the designed LC resonant bridge recovers electrical energy to realize the recovery of braking energy of the wiper motor.

9. An electronic device, comprising: It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor is configured to execute a program stored in a memory to implement the noise reduction method for an electric vehicle wiper motor as described in any one of claims 1-4.

10. A computer readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the electric vehicle wiper motor noise reduction method according to any one of claims 1-4.

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