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CN-120546518-B - Method, device, equipment and storage medium for suppressing torque pulsation of high-speed brushless direct current motor

CN120546518BCN 120546518 BCN120546518 BCN 120546518BCN-120546518-B

Abstract

The invention discloses a method, a device, equipment and a storage medium for suppressing torque pulsation of a high-speed brushless direct current motor, and belongs to the technical field of motor control. The method comprises three steps of self-adaptive harmonic suppression processing, phase compensation angle calculation and dynamic phase compensation. The invention dynamically adjusts the center frequency through the self-adaptive harmonic notch filter, suppresses dominant harmonic components in real time, combines cascaded delay signals to eliminate, filters 6k fixed subharmonics through the CDSC filter to obtain fundamental wave current signals, carries out Park conversion on fundamental wave current based on the FOC algorithm, generates a phase delay angle according to d-axis current errors through the PI controller, dynamically compensates current reference values through the reference current compensation module, and ensures phase synchronization of phase current and counter electromotive force. Compared with the prior art, the invention does not need additional hardware equipment, and reduces BLDC torque pulsation.

Inventors

  • MAO ZHONGYUAN
  • ZHONG YUANCHANG
  • ZHAO XUEHUI
  • He tengfei
  • Duan Sike

Assignees

  • 重庆大学

Dates

Publication Date
20260508
Application Date
20250527

Claims (7)

  1. 1. The torque pulsation suppression method for the high-speed brushless direct current motor is characterized by comprising the following steps of: step 1, adaptive harmonic suppression processing The method comprises the steps of collecting a three-phase current signal I a 、I b 、I c of a brushless direct current motor, inputting the three-phase current signal I a 、I b 、I c into an adaptive harmonic notch filter and a CDSC filter to inhibit dominant harmonic components in the three-phase current in real time, dynamically adjusting the center frequency of the notch filter by the adaptive harmonic notch filter based on a gradient descent algorithm so as to track and filter target harmonic components, inputting the processed signal into the CDSC filter, and filtering 6m fixed subharmonics through superposition and subtraction operation of N-level series delay units, wherein m=1, 2 is the same as the first harmonic component, N is the same as the second harmonic component, and obtaining a fundamental current signal I a1 、I b1 、I c1 ; step2, calculating phase compensation angle based on FOC algorithm Performing Park conversion on the fundamental current signal I a1 、I b1 、I c1 filtered in the step 1, and converting the fundamental current signal from a static reference system into a synchronous reference system to obtain d-axis current I d and q-axis current I q ; The d-axis current error I e =I dref －I d is obtained through the d-axis reference current I dref , I e is taken as input, and a phase delay angle is generated through a PI controller The calculation formula of the phase delay angle is as follows: in the formula, Is a coefficient of proportionality and is used for the control of the power supply, Is an integral coefficient; Step 3, FOC algorithm-based dynamic phase compensation Phase delay angle Generating compensation amounts of d-axis and q-axis current reference values by a reference current compensation module 、 The method comprises the following steps: 、 Wherein DeltaI d is d-axis reference current compensation quantity, deltaI q is q-axis reference current compensation quantity, K d 、K q is compensation gain, K d is between [0.5,1.5], K q is between [0.1,0.5], K d 、K q calculates initial value by theoretical formula, , And Is the inductance parameter of the motor and is used for controlling the motor to have high inductance, For the rated current to be the same, For the maximum allowable phase error to be present, Calculating an initial value for the electric angular velocity, and then subsequently readjusting; Reference value of current after compensation , Inputting FOC current loop, after Park inverse transformation is completed in the current loop, calculating three-phase voltages Va, vb and Vc, PWM generator according to three-phase voltage regulating duty ratio generating PWM driving signal to make real-time phase delay of phase current relative to counter electromotive force Approaching 0.
  2. 2. The method of claim 1, wherein in step 1, the objective function of the gradient descent algorithm is: where J is the mean square error function of the harmonic component, Is a harmonic current component; the center frequency update formula of the trap is: is a learning rate and ; Where ω h (k) is the trap center angular frequency at the current time, ω h (k-1) is the trap center angular frequency at the previous time, and k is a discrete time point.
  3. 3. The method for suppressing torque ripple of high-speed brushless DC motor as set forth in claim 2, wherein in step 1, the filtering target harmonic is one-time filtering for updating the primary center frequency: the filtering adopts a second-order IIR structure, and the difference equation is as follows: in the formula, Is the output after the filtering and is then output, For the current of the original phase obtained by the present sampling, Is the current latest frequency estimate obtained after h iterations, Is the pole radius.
  4. 4. The method of suppressing torque ripple of a high-speed brushless DC motor as set forth in claim 3, wherein in step 1, the CDSC filter has a series N=2, the 1 st stage filters 6 th harmonic, the 2 nd stage filters 12 nd harmonic, and each stage delays time T is an electrical period, and m is a series number corresponding to the harmonic frequency.
  5. 5. The torque ripple suppression apparatus of a high-speed brushless direct current motor of the suppression method according to claim 1, comprising: The self-adaptive harmonic notch filter is used for receiving the three-phase current signal, identifying dominant harmonic frequency, dynamically updating the center frequency of the notch filter according to the target function, performing real-time filtering by adopting a second-order IIR structure, and inhibiting target harmonic consistent with the center frequency of the notch filter; The CDSC filter is used for receiving the current data processed by the adaptive harmonic notch filter, carrying out superposition or subtraction operation on the current through N-level series delay units, filtering 6m fixed subharmonics in the current signal, and obtaining a final fundamental current signal I a1 、I b1 、I c1 ; A Park conversion unit for converting the fundamental current signal from the stationary reference frame into the synchronous reference frame to obtain a d-axis current I d and a q-axis current I q ; The comparison arithmetic unit is used for comparing the d-axis current I d with the target reference current I dref under the synchronous reference system to calculate a d-axis current error I e =I dref -I d ; a PI controller with I e as input for generating phase delay angle ; A reference current compensation module for delaying the phase by an angle Generating compensation amounts of d-axis and q-axis current reference values to obtain compensated current reference values I d * and I q * ; FOC current loop for calculating dq voltage V d ,V q from compensated current reference values I d * and I q * , performing park inverse transformation on the dq voltage, converting into three-phase voltages Va, vb and Vc, PWM generator generating PWM driving signal according to the three-phase voltage regulating duty ratio to delay real-time phase of phase current relative to back electromotive force Approaching 0.
  6. 6. An electronic device comprising a memory and a processor, wherein the memory stores a computer program which, when executed by the processor, causes the electronic device to implement the high-speed brushless dc motor torque ripple suppression method of any one of claims 1-4.
  7. 7. A computer-readable storage medium having a computer program stored therein, characterized in that the computer program, when executed by a computing device, causes the computing device to implement the high-speed brushless DC motor torque ripple suppression method according to any one of claims 1 to 4.

Description

Method, device, equipment and storage medium for suppressing torque pulsation of high-speed brushless direct current motor Technical Field The invention belongs to the technical field of motor control, and particularly relates to a method for suppressing torque pulsation of a high-speed brushless direct current motor based on self-adaptive harmonic suppression and dynamic phase compensation, and a device, equipment and a storage medium thereof. Background Brushless direct current motors (BLDC) are widely used in many high speed applications, such as compressors, blowers, and drills, due to their high torque density, high efficiency, and high reliability. As shown in fig. 1, the BLDC system includes a brushless dc motor 1 and an inverter 2, and six discrete commutation points are generally required for the existing six-step conduction control method: ab electrifying, S1 and S4 are turned on Ac power-on S1, S6 open Bc is electrified, S3 and S6 are opened Ba is electrified, S3 and S2 are opened Ca is electrified, S5 and S2 are opened Cb is electrified, and S5 and S4 are opened. The inverter 2 is triggered to commutate according to every 60 electric angles in sequence, so that the direct current power supply supplies power to the brushless direct current motor 1, and three Hall sensors H A,HB,HC are further arranged on the stator of the brushless direct current motor 1 to detect the space angle of the rotor of the brushless direct current motor on the circumference. However, there is typically a phase delay error during commutation such that the phase current is not aligned with the back emf, resulting in a large torque ripple of the BLDC. The main cause of the phase delay error in the BLDC at high speed is the hysteresis effect of the motor coil inductance, resulting in phase current hysteresis behind the back emf. In addition, at high speed, the phase current is extremely likely to generate higher harmonics, which makes calculation of the phase delay error difficult. According to the traditional method, the zero point of the counter electromotive force is used for phase inversion, and the phase current is lagged behind the counter electromotive force, so that an advance angle is needed, the current delay caused by the inductance is offset by the advance time, the phase current input into the motor is synchronous with the counter electromotive force, and the torque output by the motor is more stable. The method for eliminating the phase delay in the prior art is mainly divided into open loop compensation and closed loop compensation, wherein the open loop compensation counteracts the phase delay by phase angle conversion in advance or model prediction, but the precision of the open loop compensation is highly dependent on the accurate calibration of motor parameters and is sensitive to nonlinear effects such as inductance temperature rise and magnetic saturation, so that the dynamic response time is long, and the method is difficult to adapt to high-speed transient changes. The closed loop compensation mainly relies on a phase-locked loop (PLL) to track the counter electromotive force phase, however, harmonic interference is easy to cause PLL unlocking under high-speed working conditions, the phase difference between the intrinsic oscillation wave and the input signal is allowed to be limited by the PLL, and in addition, a high-precision encoder or an additional sensor is required, so that the hardware cost is increased significantly. Disclosure of Invention The invention aims to solve the problems in the prior art and provides a method, a device, equipment and a storage medium for suppressing torque pulsation of a high-speed brushless direct current motor, which are used for suppressing broadband harmonic interference in real time through double-stage harmonic filtering and dynamically correcting phase errors by combining d-axis current feedback, so that the problems of phase current and counter electromotive force phase delay caused by inductance hysteresis effect and harmonic pollution under high-speed working conditions are solved, and the torque pulsation of the motor is reduced. In a first aspect, an embodiment of the present invention provides a method for suppressing torque ripple of a high-speed brushless dc motor, including the steps of: step 1, adaptive harmonic suppression processing The method comprises the steps of collecting a three-phase current signal I a、Ib、Ic of a brushless direct current motor, inputting the three-phase current signal I a、Ib、Ic into an adaptive harmonic notch filter and a CDSC filter to inhibit dominant harmonic components in the three-phase current in real time, dynamically adjusting the center frequency of the notch filter by the adaptive harmonic notch filter based on a gradient descent algorithm so as to track and filter target harmonic components, inputting the processed signal into the CDSC filter, and filtering 6k fixed subharmonics through superposition and subtract