摘要
光伏并网系统中逆变器的死区及开关延时等非线性环节将会影响并网系统的稳定性及并网电能质量。为分析逆变器死区对并网系统的影响,该文首先根据逆变器的工作机理,建立包含死区效应的逆变系统开关平均模型;然后在大型光伏并网系统多逆变器并联结构的基础上推导出并网系统的等效模型,并据此探讨死区及光伏电站容量变化对并网电能质量和系统稳定性的影响。研究发现,死区效应对光伏系统相位裕度的影响随光伏系统容量的增加而降低,但光伏系统容量变化可能使系统在死区引入的谐波频率处发生不完全谐振,从而降低系统的并网电能质量。最后仿真和实验验证了理论模型的正确性。
With the increasing proportion of renewable energy such as photovoltaic power generation in the power system,the power system has higher requirements for the stability and power quality of grid-connected photovoltaic system.However,the dead time and switching delay of inverter in photovoltaic system will affect the stability and power quality of grid-connected system.In order to analyze the influence of inverter dead time on grid connected system,this paper first establishes the switching average model of inverter system including dead time effect according to the working mechanism of inverter;then,based on the parallel structure of multiple inverters in large-scale grid-connected photovoltaic system,the equivalent model of the grid-connected system is derived,and the influence of dead time and the capacity variation of photovoltaic station on grid connected power quality and system stability is discussed.Finally,the theories are verified by simulation and experiment.
作者
张前进
周林
毛明轩
解宝
李海啸
郝高锋
Zhang Qianjin;Zhou Lin;Mao Mingxuan;Xie Bao;Li Haixiao;Hao Gaofeng(State Key Laboratory of Power Transmission Equipment&System Security and New Technology,Chongqing University,Chongqing 400044,China;Postdoctoral Station of Electrical Engineering,Chongqing University,Chongqing 400044,China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2020年第9期161-168,共8页
Acta Energiae Solaris Sinica
基金
国家自然科学基金(51477021)。
关键词
逆变器
电能质量
控制系统稳定性
死区建模
光伏并网系统
inverters
power quality
control system stability
modeling of deadtime
grid-cnnected PV system
