Full Discrete Sliding Mode Controller for Three Phase PWM Rectifier Based on Load Current Estimation

This paper presents a novel full discrete sliding mode controller for voltage-sourced three phase rectifier to improve its dynamic response under the load and dc link voltage variation. Using the concept of power balance in three phase rectifier, the sliding mode controller for dc link voltage regulation is derived. Also, in order to avoid the additional load current sensor, a new method to estimate the load current is introduced. In addition, an integral sliding mode controller is applied to regulate the inductor current. The control scheme was verified in a 5 kW lab prototype. The simulation and experimental results show that the proposed control scheme has the superior dynamic response and robustness over the PI controller.