Study on PWM Rectifier Without Grid Voltage Sensor Based on Virtual Flux Delay Compensation Algorithm

Abstract

At present, virtual flux voltage oriented control strategy is one of the widely used control strategies without grid voltage sensor. To solve the dc bias resulting from voltage vector integration in vector calculation of virtual flux and further avoid the steady-state error, a virtual flux observer with negative feedback resonant filter is presented in this paper based on virtual flux principle and a delay compensation algorithm is also proposed to solve the delay of virtual flux. In addition, the control system diagram of the pulsewidth modulated rectifier without grid voltage sensor is brought forth. Then, simulation system and experimental platform are both established to simulate and test the rectifier. Eventually, the correctness and feasibility of the proposed algorithm are verified through the analysis of simulation and experimental results.