Yan Shijie

Simulation of three-phase voltage source PWM rectifier based on the Space Vector Modulation

The sinusoidal pulse width modulation (SPWM) technique is used in the conventional voltage-source PWM rectifier, and the SPWM control waveform can be obtained by the inter-phase decoupling. However, the process is complex and the utilization ratio of the DC voltage is low. This paper proposes the space vector pulse width modulation (SVPWM) control scheme for three-phase voltage source PWM rectifier, which is based on its model in synchronous reference frame. The DC bus voltage and power factor of the PWM rectifier are regulated with high performance. The paper presents the MATLAB/SIMULINK simulation model. The results confirm the validity of the model and its control method. Compared with the traditional SPWM method, the simulation results show that this method can improve dynamic performance of the system obviously.

A Neural Network Current predictive control of STATCOM for non-linear loads

This paper presents a novel current predictive control scheme based on Artificial Neural Network of STATCOM for non-linear loads which have sudden changing current. The current harmonics and power of non-linear loads, especially, uncontrolled rectifier is introduced by the instantaneous power theory. The track issue of the traditional hysteresis current control strategy of STATCOM is analyzed. In order to resolve this issue, a novel hysteresis current control scheme using the Artificial Neural Network Predictive Current Pulse Compensator is designed to predict compensating reference current waveform of the STATCOM. The method could change the STATCOM output current in advance, make the output current quickly track reference current, and then , minimize harmonics of grid current , suppress the sag of micro-grid voltage. Simulation results verified that the proposed control scheme can effectively compensate reactive power of the grid, and suppress grid current harmonics, even in sudden changing current of non-linear load.