Using a Periodic Disturbance Observer for a Motor Drive to Compensate Current Measurement Errors

Abstract

A general-purpose inverter controls the output current using information from current sensors for high-performance motor control. However, these sensors outputs, however, have some gain and offset errors that depend on the peripheral components and the characteristics of the current sensor. These errors cause an imbalance in the output current, which causes a torque ripple. The torque ripple leads to many problems. The authors have proposed a periodic disturbance observer (PDO) as a control method for vibration suppression. The current sensor error causes a vibration with a specific frequency; thus, this paper proposes a current sensor error compensation method to apply the PDO for suppressing this specific frequency. This method can suppress the harmonic current in real time, and the current control performance can be improved by error compensation. This paper explains the proposed method and demonstrates the effectiveness of the proposed method through simulation and experimental results. In addition, this paper verifies the follow-ability of sensor error variation.

High-Performance Sensorless Force Control Using Superior Wideband and Periodicity-Cancellation Force Observer

“…There are other periodic disturbance observers proposed in literature. The approach in (27) proposed a periodic disturbance observer to suppress the vibrations caused by current sensor errors in the three-phase-inverter current control. This method estimates the periodic component of the vibration and compensates for the vibration with a specific frequency using the low-pass filter and inverse system model.…”

Recent advances and outlook in industrial instrumentation and mechatronics control

“…The disturbance observer (DOB) is often termed as the pronoun of motion control technology. Hence, majority of papers related to motion control in IEEJ J. IA are related to DOB .…”

“…This system was particularly advantageous when unknown time delays were involved.Other types of advanced observers were explored by recent studies. These include the workspace observer , periodic disturbance observer , and observers considering stochastic disturbance . However, due to space limitations, the present study does not discuss these observers.…”