Reserch On Robust Control Strategy Of Three-phase Voltage Source PWM Converter

The three-phase voltage source PWM converter overcomes the disadvantages of traditional uncontrolled rectifier and phase controlled rectifier with high harmonic and low power factor,and has the advantages of high sinusoidal input current,high power factor,bidirectional energy flow,etc.It has been widely used in the field of electric energy coversion.Firstly,this article introduces the basic working principle of the three-phase voltage source PWM converter and the development situation,and constructs the mathematical model of the three-phase voltage PWM converter in abc,?? and dq coordinate system.On this basis,the proportional integration observer(PIO)is used to improve the anti-interference ability of the dual closed-loop control system of the three-phase voltage PWM converter.The detailed design process of PIO is given,and the stability of the system is analyzed by using the pole figure.Simulation and experimental results show that,compared with traditional double closed-loop control strategy,the proposed robust control strategy has the advantages of high sinusoidal degree of AC side current and low voltage fluctuation of dc bus when there is external interference.And it is simple and easy to implement.