Analysis Of The Effects Of Photovoltaic Power Station Model On The Study Of Voltage Stability

With the sustainable development and the high speed development of economyin our country, the demand for clean energy is increasing, the capacity and scalephotovoltaic (pv) grid increases constantly, the influence on the stability of powersystem voltage from grid-connected Photovoltaic system is becoming more and moreprominent, there is serious influence the development of large-scale photovoltaicpower generation systems. Therefore, for the nonlinear behavior of photovoltaic gridpower generation system to conduct the thorough research to the voltage stability hasimportant practical significance. In this paper, based on the structural feature ofphotovoltaic power station, in-depth study the running mechanism of photovoltaicgrid power generation system. According to the different priorities established adifferent model of photovoltaic power station, and get the whole model of the entirephotovoltaic grid system is different. Through respectively choose photovoltaicpower station output active power and active power load with the busbar voltage as asingle parameter bifurcation diagram. Compared with photovoltaic power stationmodel of bifurcation theory to study the effect of voltage stability analysis. Theconcrete research content is as follows:firstly, This paper introduce the basic concept of the development ofphotovoltaic grid-connected system, the concept and determination methods ofvoltage stability in power system, the bifurcation theory in the application of powersystem voltage stability research and the use of the bifurcation analysis softwareMATCONT methods and techniques are reviewed.On the basic of research and analysis on the principle and characteristics ofphotovoltaic power station, the research use method of small signal, the controlledsource of photovoltaic power station, a simplified method to analysis, then set upphotovoltaic power station model by the small signal, the model of simplifiedcontrolled source model.Further, base on the bifurcation theory, the research studied the different model of photovoltaic power station on the photovoltaic grid system voltage stabilityanalysis, and the influence of and bifurcation diagram of different model offers anexplanation for this.The results of the application of bifurcation theory and bifurcation analysissoftware MATCONT proceeds show that the model of photovoltaic power stationselection effects of using the theory of bifurcation analysis of the results of thephotovoltaic power grid system. But on the whole, for whatever reason, photovoltaicpower plant model, the influence on power system voltage stability is the same, isonly a saddle node bifurcation point, so that we can draw a photovoltaic power stationmodel on qualitative does not affect the voltage stability using the bifurcation theoryresearch. Therefore, in using the bifurcation theory of photovoltaic power station gridinfluence on power system when doing qualitative research can choose relativelysimple, reasonable simplified model. But if you want to get the precise impactanalysis, should choose the photovoltaic power station will all intermediate nonlinearcomponents included in the model. And because that the simplified models omitintermediate nonlinear link, then this model is not suitable for dynamic voltagestability of the research model.The conclusion of this article research has a certain reference value on theselection of photovoltaic power station grid system application of bifurcation theoryto study the system voltage stability affected model.