Review of Grid-Connected Solar PV Systems With Decoupled Control

This paper presents a decoupled control for grid-connected solar photovoltaic (PV) system. The control framework used in this paper aims not to track the changing maximum power point (MPP) for extracting power at MPP, hence blocking the MPP tracking issue against the effect of solar radiation and temperature. Real power is produced by tracking the control voltage with a zero-dynamics-based controller. A cascaded loop controller with inner loop to regulate the control voltage is incorporated to ensure the produced real power follows the reference power in the presence of power disturbance. The proposed control scheme with the consideration of the inverter's rated voltage shows improved system dynamics. Simulations in various conditions are conducted to prove the effectiveness of the proposed control strategies. CIGRE 13-node benchmark system is used as the case study to evaluate the results of the PV system connected to a more complex power system. It has been shown that the proposed controller allows the total production of the energy under maximum power point conditions and also improves the overall stability of distributed generation connected to the grid. Therefore, it can be implemented to increase the capacity of renewable inverter-based power generation and the power system quality.