Research on Double Closed-loop Control Strategy and Grid-connected Stability of Photovoltaic Power Generation System
A grid-connected operation control method of photovoltaic inverter based on double closed-loop control is investigated in this paper. The double closed-loop control is composed of an outer ring and an inner ring. The outer ring adopts the proportional inte-gral control method to maintain the voltage stability of the DC bus of the grid-connected inverter. The power grid voltage feedforward compensation control is introduced into the inner loop to improve the traditional double closed-loop control strategy. The inner loop u-ses the compound control mode of AC current feedback combined with power grid voltage feedforward to implement SPWM control on photovoltaic grid-connected inverters to suppress the disturbance caused by voltage fluctuations of the public grid to the photovoltaic power generation system,finally realizing stable control of frequency and power output. Based on the improved double closed-loop control method a simulation model of two-stage grid-connected photovoltaic power generation system is built. The results verify the feasibility and effectiveness of the control method.
Photovoltaic power generationInverterGrid-connected controlDouble closed-loop
万方数据
维普
