Study On Voltage Regulation Control Strategy Of Photovoltaic Inverter System Connected To Distribution Network

Solar photovoltaic power generation is an effective way to achieve large-scale development and utilization of solar energy. Due to the volatility of the PV power, distributed PV provides power for nearby users, which brings more limitation on voltage to avoid distribution network power quality problem. This article is based on analyzing the distributed PV voltage characteristic of distribution network at the access point. The distributed PV systems was deeply studied which involved in grid voltage regulation control strategy. In to improve performance of distribution network with a large number of distributed photovoltaic power generation system, this control strategy has important theoretical significance and practical value.Firstly, the mathematical model of photovoltaic was built through inference and study on analyzing impact of the output characteristics under vary external environment conditions. The gird-connected inverter model for PV generation was established. Using the model, grid voltage oriented vector control is deeply researched.Because of accessing distributed generator, the influence of generator to distribution network steady-state voltage was analyzed. Flow calculation is applied to obtain the voltage distribution characteristics under interconnecting distributed power sources or not. The influence of distribution network voltage which was brought by connecting distributed generator was analyzed under the vary condition of PV power output and locations. Based on IEEE 33 test system, the simulation show the influence to the ideal distribution network from distributed generators.Finally, the reactive power control strategy facing the grid voltage regulation connected to distribution network is proposed, which is aimed to control PCC voltage by compensating system reactive. The simulation experiment of voltage and reactive power regulation in different load and PV injected power was finished. Based on Dalian Haikun PV systems, the effectiveness of the proposed strategy is verified.