A New Theory of Reactive Power Control of Grid Connected PV Inverter

In recent years, with the rapid development of solar energy and other renewable energy, PV grid connected power generation technology has more and more attention. Grid connected inverter is the core of grid connected power system. When grid connected inverter operated in grid, the current control mode is essentially a voltage source input and current source output of the inverter. At present, a lot of work has been carried out in the aspects of filter selection, grid connected control strategy and controller design in the domestic and abroad, aiming to improve the power quality of grid connected current. In this paper, the reactive voltage control strategy of grid connected photovoltaic system is studied in order to increase the penetration rate and improve the stability of grid voltage. Grid connected PV system generally consists of a number of inverters, so it is necessary to analyze the control strategy of a single inverter and the reactive power output constraints.