A novel control technique for various modes of grid-connected PV system to improve power quality.

A novel control strategy for a single grid-connected PV system with power backup in different modes of operation, including constant load, changing atmospheric circumstances, and load variable conditions. The proposed controller works with a large nonlinear load under different modes of operation. The controller operates in such a way that, it can achieve different functions such as maintaining power flow between the photovoltaic (PV) module to the grid, maintaining UPF (unity power factor) at the point of common coupling(reactive power compensation), synchronizing a grid with PV (grid current harmonics compensation) and regulates the operation of battery(charging or discharging) for electric vehicle application. Implementing the proposed controller reduces the complexity of the active shunt filter at the point of common coupling (PCC). A maximum Power Point (MPPT) controller, optimized with perturb & observe (P&O)algorithm is used to get optimum power from the PV module. Thesimulation findings validate the operation of the suggested controlstrategy in a grid-connected PV system with a battery backup topology.