Novel single phase Dynamic Voltage Restorer based on DC-modulation AC/AC technique

A new idea of using DC-DC modulation AC/AC technique instead of a transformer to link Dynamic Voltage Restorer (DVR) to the transmission line is proposed in this paper. Dynamic voltage restorer is used as series compensation to mitigate voltage disturbances. This paper presents a transformerless DVR that can mitigate long duration voltage sags and swells with lower losses and a flexible AC/AC conversion ratio. The use of DC-modulated AC/AC converters is a new technique that allows the DVR to be connected directly to the distribution network without using a costly and bulky injection transformer. Simulation results are presented to demonstrate the efficiency against voltage disturbances of proposed DC-modulation technique used to replace the transformer in DVR application.