Combined operation of a VSC based grid interfaced solar photovoltaic power generation system with night time application

A 4-leg VSC (Voltage Source Converter) based SPV (Solar Photovoltaic) power generating system is integrated to a 4-wire distribution system using MISCT (Modified Instantaneous Symmetrical Component Theory) based control algorithm. This MISCT is used to estimate reference currents to control 4-leg VSC. The control algorithm is used to balance the loads and to improve the power factor of ac mains. The PCC voltage is maintained at reference value by required reactive power compensation by VSC and its DC link voltage is regulated using a PI (Proportional-Integral) controller. Performance of proposed SPV generating system is simulated using MATLAB/Simulink and sim-power system toolboxes. Simulation results of the proposed system are demonstrated for improved power quality of a three phase 4-wire distribution system for load balancing, harmonics elimination, neutral current compensation, voltage regulation and power factor correction.