微网孤岛运行模式下的调频控制策略

针对采用下垂控制的逆变器组成的微网,研究其孤岛运行模式下的调频控制策略。通过对系统进行建模分析,并将传递函数进行有效的等效与化简,推导出调频控制器的参数校正公式。当系统工况改变导致分配特性、输出阻抗以及接入条件改变时,该控制器都可以在线调整参数值,使系统频率迅速恢复稳定。实验结果证明,引入该参数自动调节算法后,系统参数改变时调频控制算法可以很快恢复到给定频率,并保持频率稳定。

Frequency Regulation Control Strategy for Microgrid in Islanded Mode

In view of the microgrid consisting of inverters controlled by droop method, a frequency regulation strategy for the microgrid in the islanded mode is studied. Through the modeling and analysis of the microgrid system, as well as the equivalent and simplification of transfer functions, a parameter correction formula for the frequency regulation controller has been derived. When the system condition changes result in distribution ratio altering, output impedance changing and the varying of access number of inverters connected to the microgrid, the controller is able to adjust parameters online for quick restoring the system frequency to stability. Experimental results show that, the system frequency can quick recover to the given value and keep steadily due to the parameter auto-adjustment algorithm. This work is supported by National Natural Science Foundation of China(No. 51541703)and Innovative Research Team Funded Program of Guangdong Province(No. 2011N015).