微电网光伏发电系统控制与稳定性研究

在分析光伏电池原理及最大功率跟踪基础上,分析了含光伏发电系统的微电网模型。对光伏系统控制采用的是两级式控制,前级Boost DC/DC实现光伏阵列最大功率跟踪控制以稳定直流母线电压,并可升高电压以满足后级逆变器需要。后级为DC/AC逆变器,对逆变器采用V/f控制策略,此控制策略用以保证微电网的频率电压的稳定性。在Matlab/Simulink平台搭建含光伏发电系统的微电网仿真模型,分别对在并网运行时改变光照和在孤岛运行时改变负荷进行仿真,验证控制策略能够保证光伏发电系统的稳定运行。

Study on the Control Strategy and Stability for Photovoltaic System of Microgrid

In this paper,the principle of the photovoltaic cells and the theory of photovoltaic arrays maximum power point tracking is analyzed,and a microgrid of photovoltaic system model is built.The boost DC/DC chopper in series with an inverter is adopted in the inverter system.The boost chopper changes the output voltage of the PV array by adjusting the duty cycle.The inverter is controlled by V/f control strategy.With this strategy,the stability of micro-grid voltage and frequency may be ensure.The correctness of the control strategy and stability of the photovoltaic system are verified based on Matlab/Simulink,which is by the illumination changes in grid-connected photovoltaic and load changes in autonomous operation.