The Wind generation system has potential application for the grid support that could be utilized in rural areas. However, continuous variation of wind speed results in severe power quality problems, especially in a standalone village network. In distributed generation, wind power system can cause sub harmonic and interharmonic components to appear in the spectrum of voltage and currents. These harmonics can cause flicker, overload, and interference, on the electronic equipments. This paper proposes Dynamic Voltage Restorer (DVR), which is the most efficient and effective modern custom power device used in power distribution networks. This could be used to improve the power quality in a rural load fed from a wind driven permanent magnet synchronous generator (PMSG). The reference voltage is tracked by voltage source converter using a switching band scheme. A method of extracting the phasor symmetrical components that contain both integer and non integer harmonics and complex Fourier transform relation is proposed. In this paper, it is demonstrated that this device can tightly regulate the voltage at the load terminal when load draws integer, non integer harmonic current and sag and swell in the source side.
Four Leg Voltage Source Converter based Dynamic Voltage Restorer for Power Quality Improvement in Distribution Networks