Dynamic Voltage Restorer Controlled with Energy Minimized Compensation Method Based on Multi-level Ground Point Shifting Inverter

Nowadays, integration of intermittent and distributed renewable energy generations into power grid causes to have power quality problems as concern. These problems are usually causing very costly consequences such as production line and/or sensitive load interruption. Hence, it is crucial to have stable voltage with good quality. One of the most effective power-electronics-based approach to alleviate the mentioned problems is dynamic voltage restorer (DVR). DVR is capable to restore the voltage at load side whenever grid voltage is disturbed. This paper present a new configuration of DVR based on five-level ground point shifting multilevel inverter The proposed inverter has a floating ground point. Therefore, by shifting the ground point, it is observed that the inverter circuit gives five output voltage levels from single DC voltage source. This configuration uses less number of switches compared to the existing multilevel inverter topologies In order to minimize the required energy from energy storage, the energy optimized strategy is implemented to compensate the voltage sag. Furthermore, d-q synchronous reference frame-based method is implemented to calculate the DVR reference voltages The proposed DVR is simulated using MATLAB/Simulink software and simulation results are presented to validate its effectiveness.

Ground Point Shifting Multilevel Inverter (GPSMI), Dynamic Voltage Restorer, Voltage Sag, Voltage Swell, Voltage flicker, Power Quality