摘要
此处主要对弱电网下考虑电网阻抗和设备间线路阻抗时并联有源电力滤波器(APF)系统进行研究。当仅考虑电网阻抗时,并联APF系统中每个APF系统均采用电容串联电阻的无源阻尼,系统稳定运行。但由于设备间存在线路阻抗,并联系统中APF通过公共节点电压相互耦合,易产生谐振。由此建立APF多机并联模型,结合公共耦合点矩阵方程,对系统谐振问题进行分析。通过分析,当考虑电网阻抗和设备间线路阻抗时,仅采用无源阻尼的APF系统不再稳定,即使引入基于电容电流的有源阻尼,也不能消除APF的谐振,且设备的公共耦合点周围阻抗越复杂,谐振现象越严重。为此,在此引入基于公共耦合点电压前馈的有源阻尼,针对该矩阵提出的有源阻尼模型,得到不同电网阻抗时系统的幅频特性曲线,可知该方法能够有效抑制并联产生的谐振。最后通过搭建仿真和实验平台,验证上述理论分析的正确性和抑制策略有效性。
The parallel active power filter(APF)system considering the grid impedance and the line impedance between equipment in weak power grid is mainly studied.When only the grid impedance is considered,each APF system in the parallel APF system adopts the passive damping of a capacitor in series with a resistor,and the system operates stably.However,due to the line impedance between the equipment,the APF in the parallel system is coupled with each other through the common node voltage,which is easy to produce resonance.The multi-machine parallel model of APF is established,and the resonance problem of the system is analyzed combined with the common coupling point matrix equation.Through the analysis,when considering the grid impedance and the line impedance between the equipment,the APF system with only passive damping is no longer stable.Even if the active damping based on capacitive current is introduced,the resonance of APF can’t be eliminated,and the more complex the impedance around the common coupling point of the equipment,the more serious the resonance phenomenon.Therefore,the active damping based on the voltage feedforward at the point of common coupling is introduced,the active damping model is proposed for the matrix,and the amplitude-frequency characteristic curves of the system at different grid impedance are obtained,which shows that this method can effectively suppress the resonance caused by parallel connection.Finally,a simulation and experimental platform is built to verify the correctness of the above theoretical analysis and the effectiveness of the suppression strategy.
作者
刘鑫
戴强晟
刘斌
徐可心
LIU Xin;DAI Qiang-sheng;LIU Bin;XU Ke-xin(Nanchang Hongkong University,None hang 330063,China;不详)
出处
《电力电子技术》
北大核心
2023年第9期62-66,94,共6页
Power Electronics
基金
国家自然科学基金(61963030)
关键词
滤波器
复杂阻抗
多机并联
有源阻尼
filter
complex impedance
multi-machine parallel
active damping
