SMO-ESO-Based Voltage Sensorless Model Predictive Control for PWM Rectifier

Abstract

In common usage of three phase voltage source PWM rectifier in industrial transmission system, the control effect of DC bus voltage is related to the safety of the system. This paper presents a voltage sensorless control strategy in order to avoid the outer loop feedback distortion caused by DC voltage sensor fault. The idea of combining bus voltage observer with model error rolling optimization is proposed firstly. And a model predictive power control (MPC) method without bus voltage sensor is designed in this paper. For the PWM rectifier, based on MPC, a bus voltage observer combining sliding mode observer (SMO) and extended state observer (ESO) is designed to cope with the problem that the bus voltage is unobservable and the estimation accuracy is poor in special switch state using traditional sliding mode observer. Finally, by setting an adaptive threshold, the observer is used to realize the rapid reconstruction of the system in the case of sensor fault, so as to ensure the normal operation of the rectifier.