Operate Independently Of Ann More Than 100kwp Pv Power System Transient Stability Analysis

Because of the problems in the working stand-alone photovoltaic power systems, this paper analyzed the characters of the structure and working mode of this kind of power system and judged which kinds of these problems belong to. Choosing the 100kWp stand-alone photovoltaic power system which was built at Sitsang Anduo county as the research object, and using the methods which are used in analyzing the normal power system, we determined that the problems which happened when the load was launched into the system could be classified as the transient stability problem of power system. After more research, we found the main reason of this problem is the unbalance of reactive power in this kind of power system.Analyzing the problem and the characters of the stand-alone photovoltaic power system, we can chose the numerical simulation method in time-domain to analyze the transient stability of the photovoltaic power system. And we chose the power system tool-box of the Matlab Simulink as our simulation tools to realize the numerical simulation calculation of the stand-alone photovoltaic power system. Here we use the concept of instantaneous reactive power when we simulate the system, we can use them to analyze how they affect the power systems stability.To validate the analysis, referring the real photovoltaic power system, we made a simple experiment system which included an inverter. From the results of simulation and experiments, we can conclude that the unbalance of reactive power is the main reason which make the stand-alone photovoltaic power system suffer transient stability problem which behaved as the voltage waving. So adding some kind of reactive power compensation equipments is a good solution to the working systems. And in the future design of the stand-alone photovoltaic power system, on the based of analyzing the reactive power, we can deal with this problem by reasonably arranging the load and in some situation adding some kind of reactive power compensation equipments. In this way, we can arise the stability of this kind of power system and make them work better.