Dynamic voltage restorer using push-pull inverter

Proliferation of the voltage-sensitive loads in the distribution systems has made the voltage quality an important issue. The main factors considering the voltage quality are the voltage sags and voltage swells. There are many available solutions to improve voltage quality. In the past years, application of the power-electronic based devices known as custom power devices have developed an interesting solution to the voltage quality problems. Dynamic voltage restorer (DVR) is one of the custom power devices which is well suited to the voltage sag and voltage swell compensation. This paper proposes a new DVR which is based on the push-pull inverter with only two switching devices for a phase. As a result, the proposed topology offers reduction of the switches which leads to decrease in the number of switches driver circuits and control complexity. The operation of the proposed DVR is demonstrated using simulation results in the PSCAD/EMTDC software.