摘要
针对目前规避电网谐波危害而采用的滤波方法的不足,在建立民用建筑低压侧等效电路模型并分析参数与补偿电容容量及变压器规格等发生并联谐振时的关系,剖析系统并联谐振机制的前提下,结合并联电容器长期运行电压极限值,构建系统无功补偿过电压判据,优化并联电容器组投切策略。针对某一民用建筑物的低压(0.4 kV)配电系统,基于实际测量的母线电压U_L、负荷侧电流i_L与无功补偿并联电容器组电流i_c,分析其电流电压谐波特性;利用系统无功补偿过电压判据进行过电压规避,并进行仿真验证,以此形成一套可推广到其他民用建筑的规避过电压的方法。
Considering the deficiencies of the existing filtering methods to avoid the harm of power grid harmonic,this article comes up with an optimized strategy.By establishing the equivalent circuit model at the low-voltage side of civil buildings and analyzing the relationship among the parameters of capacitor,the capacitance of the compensation capacitor and the size of the transformer when parallel resonance happens,an overvoltage criterion of reactive power compensation is constructed with the assistance of the analysis on parallel resonance mechanism of reactive power compensation system and based on the limited value of long-term operating voltage of shunt capacitors,and the switching strategy of shunt capacitor banks is optimized.A low-voltage（0.4 kV） power distribution system of a civil building is chosen,and based on the actual measurement of its bus voltage U_L,the load-side current i_L and reactive power compensation shunt capacitor banks current i_c,its current and voltage harmonic characteristics are analyzed.The criterion is used to avoid overvoltage,and simulation verification is also made,based on which,a method is formed which can be extended to other civilian buildings to avoid overvoltage.
作者
刘智谦
杨典语
王晓丹
LIU Zhiqian YANG Dianyu WANG Xiaodan(School of Electrical Engineering, Chongqing University, Shapingba District, Chongqing 400044, Chin)
出处
《智能电网》
2016年第9期901-907,共7页
Smart Grid
关键词
单相谐波电流源模型
并联谐振
过电压判据
电容器组投切
single-phase harmonic current source model
parallel resonance
overvoltage criterion
shunt capacitor bank switching
