基于虚拟同步发电机的微网频率控制研究

Frequency Control Strategy of Micro-grid Based on Virtual Synchronous Generator

随着分布式电源在电网中的渗透率越来越高,针对传统并网逆变器控制策略存在低惯性、欠阻尼以及无法对微电网内部频率进行有效控制的问题。提出了基于虚拟同步发电机(VSG)技术的光储型微网频率控制策略,孤岛模式下利用下垂系数与PI调节器来模拟传统一次调频与二次调频的过程,减缓负载突变对系统频率的影响,实现了频率的无差控制。建立了VSG的数学模型,详细介绍VSG控制策略,并利用Matlab/Sinmulink仿真平台搭建了VSG仿真模型。对控制策略进行了仿真验证,仿真结果验证了所提控制策略的有效性与可行性。

In this paper,the frequency control strategy of photovoltaic and stored type micro-grid,which based on virtual synchronous generator（VSG）,is proposed.Under islanding mode,in order to mitigate the influence on system frequency of load sudden variation and achieve the frequency control of without any static error,the droop coefficient and PI controller are applied to simulate the traditional process of primary and secondary frequency modulation.The mathematical model and control strategy of VSG is introduced in this paper.