Method for suppressing bias error of current measurement of permanent magnet synchronous motor based on signal injection

By injecting a sinusoidal signal into the permanent magnet synchronous motor drive system and utilizing a band-stop filter of a second-order generalized integrator, combined with amplitude and phase compensation, the problem of motor performance degradation caused by current sensor bias error is solved, achieving low-intrusion and highly robust bias error suppression, suitable for various operating conditions.

CN122394451APending Publication Date: 2026-07-14SOUTHWEST JIAOTONG UNIV +1
View PDF 0 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
SOUTHWEST JIAOTONG UNIV
Filing Date
2026-04-24
Publication Date
2026-07-14

AI Technical Summary

Technical Problem

In existing permanent magnet synchronous motor drive systems, current sensors are susceptible to bias errors due to electrothermal stress, leading to motor speed fluctuations and torque pulsations. Existing suppression methods rely on motor parameters and are easily affected by parameter changes, making it difficult to guarantee high-performance system operation.

Method used

By employing a signal injection-based method, a sinusoidal signal is injected and a band-stop filter of a second-order generalized integrator is used. Combined with amplitude attenuation and phase deviation compensation, the bias error can be effectively estimated and eliminated. The design is simple and does not require changes to the motor structure.

Benefits of technology

It achieves high-performance operation under different working conditions, suppresses bias error without the need for motor parameters, has low intrusion and high robustness, low computational burden, and is suitable for various permanent magnet synchronous motor drive systems.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN122394451A_ABST
    Figure CN122394451A_ABST
Patent Text Reader

Abstract

The application discloses a signal injection-based permanent magnet synchronous motor current measurement bias error suppression method, which comprises the following steps: analyzing the influence of bias error on the performance of a permanent magnet synchronous motor driving system; designing a signal injection-based bias error suppression method, extracting an injected signal response by using a band-stop filter based on a second-order generalized integrator, and realizing online suppression of the bias error; aiming at the amplitude attenuation and phase deviation caused by the band-stop filter, adopting an amplitude compensation factor and a signal delay-based phase compensation strategy to guarantee the bias error suppression performance; and building a small-power permanent magnet synchronous motor driving system experimental platform for verification. The application does not need motor parameters, can avoid the adverse effects of motor parameter changes, has the characteristics of accurate measurement, strong robustness, low calculation burden and wide applicability, and can be popularized and applied to the bias error suppression of current sensors of various permanent magnet synchronous motor driving systems, thereby providing key technical support for the high-performance operation of motor driving systems.
Need to check novelty before this filing date? Find Prior Art