虚拟同步发电机暂态频率建模及特性分析

Transient Frequency Modeling and Characteristic Analysis of Virtual Synchronous Generator

大规模风电、光伏等新能源机组接入电力系统,将极大地改变系统的电源特性,使系统转动惯量水平下降,威胁系统的暂态频率稳定安全。虚拟同步发电机技术能够增强新能源机组对系统的惯量支撑能力,促进系统频率稳定。为了定量描述虚拟同步发电机的暂态特性,增强对VSG的控制能力,虚拟同步发电机的暂态频率建模亟需研究。基于新能源机组虚拟同步发电机控制策略,考虑新能源机组惯性响应、一次调频等特性,建立了虚拟同步发电机的暂态频率响应模型,搭建了Matlab/Simulink仿真模型,验证了所建立的解析模型的正确性。最后,分析了不同控制参数对虚拟同步发电机暂态频率响应的影响,明确了控制参数对虚拟同步发电机暂态频率响应的作用规律,为控制新型电力系统频率稳定指明了方向。

The integration of large-scale wind power,photovoltaic and other renewable energy resources for the power system will greatly change the power supply characteristics,reducing the inertia of power system and threatening the stability of transient frequency.The virtual synchronous generator(VSG)technology can improve the inertia of renewable energy to promote the stability of transient frequency.In order to quantitatively describe the characteristics of transient frequency of VSG and enhance the control ability of VSG,the transient frequency model of VSG needs to be studied urgently.Based on the VSG control strategy of renewable energy,considering the inertial response,primary frequency regulation of renewable energy,the transient frequency model of VSG was established,and a Matlab/Simulink based simulation model was built to verify the validity of the established analytical model.Finally,the influence of different control parameters on the transient frequency of VSG was analyzed,and the effect of control parameters on the transient frequency of VSG was clarified,giving the guidance for system frequency stabilization.