Reliable current control for single‐phase pulse width modulation rectifiers based on H_∞ loop shaping controller

Abstract

In this study, H∞ loop shaping is designed for single‐phase pulse width modulation (PWM) rectifier under current sensor gain faults. Pre‐compensator is used to obtain the desired loop shape at all frequencies and robust stabilization through the normalized coprime factorization. The mathematical model for the rectifier is developed to obtain the nominal plant transfer function, and two algebraic Riccati equations are used to solve the designed controller and obtain the loop shaping controller by combining the designed controller with the weights. ν‐gap metric is adopted to measure the magnitude of the current sensor gain fault that can be stabilized by the controller. The proposed controller is compared with H∞‐mixed sensitivity (H∞‐MS) controller. The robustness capability and dynamic performance is investigated and, hardware‐in‐loop experimental results show excellent balance between robustness and performance in the presence of current sensor gain faults.