应用于微电网的并网逆变器虚拟阻抗控制技术综述

摘要

微电网是由分布式电源、储能装置和负荷等组成的统一整体,随着分布式电源渗透率的不断提高,微电网的应用越发广泛.在实际运行中,微电网中通常会出现并联逆变器功率分配不均、谐波污染、串并联谐振、故障电流和励磁涌流过大等问题.虚拟阻抗技术能够改变并网逆变器的阻抗特性,对于上述问题的解决效果颇佳,而且实现简单,因此具有广泛的应用前景.全面综述了虚拟阻抗的应用场景和相应的实现方法,并结合自适应虚拟阻抗这一现阶段的研究热点,探讨了未来的研究趋势和可能遇到的关键问题.%Microgrid is a unity composed of distributed generation,energy storing devices and load.As the penetration of distributed generation increasing,microgrid application domain is more extensive.Some problems often occur in microgrid,such as parallel inverter power distribution imbalance,harmonic pollution,series parallel resonance,fault current and inrush current.Virtual impedance technology which is achieved easily can change the impedance characteristics of grid-connected inverters and solve the above problems effectively,hence this technology has broad application prospects.This paper comprehensively introduces the application scenarios of virtual impedance and corresponding implementation methods,combined with adaptive virtual impedance that is the current hot research topics,and discusses the future research trends and key issues that may be encountered.