Velocity Control for Ripple Reduction in Permanent Magnet Synchronous Motors With Low Performance Current Sensing

Abstract

In this study, a velocity control method is proposed for minimizing velocity ripples in permanent-magnet synchronous motors with low-performance current sensing. The proposed method involves the use of desired currents, peak estimation, and a proposed tracking controller. The desired currents are used to achieve velocity control with only the current sensing. Peak estimation is performed to estimate the peak of the measured distorted current that occurs due to low-performance sensing. The proposed tracking controller is developed based on a proportional-integral controller using the estimated peak obtained from the measured currents. The proposed method aids in reducing velocity ripples and improving velocity tracking performance of permanent-magnet synchronous motors. The primary contribution of this method is the improvement of velocity-control performance with low-performance current sensing. The stability of the closed loop is proven by employing the input-to-state stable property. To verify the effectiveness of the proposed method, we performed simulations and experiments with different three cases. INDEX TERMS Velocity control, ripple reduction, peak estimation, low-performance current sensing, permanent-magnet synchronous motor.

A Robust Method Based on Dual Encoders to Eliminate Velocity Ripple for Modular Drive Joints

“…Modular drive joints are now widely used in industrial robots and collaborative robots, integrating high efficiency and high power density permanent magnet synonym motors (PMSMs), harmonic drive, torque sensors, shafts, bearings, dual encoders, and other components [1][2][3]. The PMSM is widely employed in modular drive joints due to its advantages: fast dynamics, high efficiency and reliability, and a favorable torque to inertia ratio [4][5][6].…”