A New PV-Open-UPQC Configuration for Voltage Sensitive Loads Utilizing Novel Adaptive Controllers

In this article, a novel topology for photovoltaic (PV) fed open unified power quality conditioner has been proposed focusing on the requirement of voltage sensitive loads. It has incorporated the advantages of open unified power quality conditioner (UPQC) and grid connected PV systems by providing a possible solution towards the demand of different power quality levels at end user. Increasing the system robustness for various voltage and current distortions, adaptive controllers have been implemented for series and shunt compensators of UPQC. Adaptive notch filter based improved Syncronous Reference Frame (SRF) scheme has been utilized for the control of series compensator. An adaptive logarithmic absolute algorithm has been implemented for shunt part of proposed system. The utilization of moving average filter (MAF) instead of low pass filter (LPF) for dc bus voltage regulation has neglected the chance of high as well as low frequency ripples. A feed forward component has been added to the shunt controller to regulate the grid current at constant level in presence of grid disturbances. The proposed controllers are verified on a developed prototype of proposed system in the laboratory. The system performance is found satisfactory under various grid conditions like voltage sags, voltage swells, voltage unbalance, voltage harmonics, sudden load addition and removal, and variation in solar irradiation.