自同步电压源逆变器控制策略研究

Research on the Control Strategy of Self-synchronous Voltage Source Inverter

新能源发电在电力系统中渗透率不断提升给电力系统的稳定性带来了影响。为提高电力系统稳定性,这里研究和讨论了自同步电压源逆变器控制策略。利用同步发电机转子运动方程、一次调频调压特性,虚拟同步机的"惯量",建立自同步电压源逆变器的数学模型,研究了自同步电压源逆变器有功/频率动态响应特性,并分析了主要控制参数对系统稳定性及动态响应的影响。仿真和实验表明,自同步电压源逆变器在外特性上近似等效为一个同步发电机,具有良好的调频调压性能,能很好地适应电网的运行要求。

The increasing penetration of new energy generation in power system has brought the impact on the stability of power system.In order to improve the stability of power system, the control strategy of self-synchronous voltage source inverter is studied and discussed.The mathematical model of self-synchronous voltage source inverter is constructed by using synchronous generator＇s rotor motion equation and primary frequency regulation feature and virtualizing the inertia of synchronous machine.How to improve the active power/frequency dynamic response characteristics of the self-synchronous voltage source inverter are discussed and the effects of main control parameters on the stability and dynamic response of the system are analyzed.Simulation and experimental results demonstrate that self-synchronous voltage source inverter is approximately equivalent to a synchronous generator in the external characteristic and the presented control strategy has good frequency modulation and voltage regulation performance.