Photovoltaic based DVR with Power Quality Detection using Wavelet Transform

The increased usage of non-linear loads, abrupt switching of heavy loads and line faults have flared up the power quality issues to greater extent. This paper deals with a Photovoltaic based Dynamic Voltage Restorer to compensate any voltage deviations or disturbances that occur in a system caused by such power quality issues. The DC link capacitor of the DVR is supplied by the PV panel which supplies the load as well, thereby, considerably reducing the power drawn from the grid. A charge controller and associated DC-DC converter takes care of the charging and discharging of the batteries as well as supplying the remote DC and AC loads. A switching controller based on Wavelet Transform is developed to detect any power quality event that occurs and automatically switch the DVR to inject the compensated voltage. With the effect of Wavelet Transform, the switching of DVR is done faster.