Research Of Impact Of Grid-connected Photovoltaic Power Generation System On Distribution Network

With a gradually serious problem of the global environmental pollution and energy shortages, exploiting new energy sources is necessary to cover the future demands. Solar energy is one of the most abundant, clean, and large scale regeneration energy resources. Photovoltaic grid-connected technology have become the main form of the PV application. With the growing capacity, PV system has an effect on existing power systems, Meanwhile incorporating PV system will bring a series of technical problems, The paper diseusses the impact of PV system on power flow , voltage profile and relay protection.Fristly, the grid-connected model is studied in this paper, the grid-connected PV system which includes photovoltaic array, maximum power point tracking module, inverter module is established, and simulation results show the effectiveness of the PV array, MPP control algorithms and the system model; the impact of PV system on power flow and voltage profile of distribution network are analyzed, the impact rule of power flow and voltage profile according to the different positions, capacity and working states are studied by simulation using the PSASP, the technical measures and control strategies are proposed. Analysing the characteristics of PV system, the degree of fault currents are studied by simulation using the PSASP, and the impact of different interconnecting locations, different capabilities and different fault points of PV system on short current and relay protection are analyzed, the different strategies are taken for this.