Modeling and Simulation of PWM Switched Autotransformer for Voltage Sag Mitigation Using MATLAB

This study addresses the modeling and simulation of a new voltage sag mitigation technique is presented besides custom power devices like dynamic voltage restorer and STATCOM are normally employed as a solution for mitigation of voltage sag and swell. In this study, modeling and analysis of PWM switched autotransformer that can compensate during voltage sag and swell condition is discussed. The proposed system has less number of switching devices and has good compensating capability in comparison to commonly used compensators. Simulation analysis of three-phase compensator is performed in MATLAB/SIMULINK and performance analysis of the system is presented for various levels of sag and swell. Also, the compensator can maintain the load powers both real and reactive powers constant. Simulation results are presented for various conditions of sag and swell disturbances in the supply voltage to show the performance of the new mitigation technique.