新接入负载和背景不平衡发射水平的分离  

Separation of New Access Load and Unbalanced Background Emission Levels

作　　者：邓厚兵[1] 佟子娟 许磊[3] 孙永琴 

机构地区：[1]中国南方电网超高压输电公司南宁局,广西南宁530014 [2]国网冀北电力有限公司廊坊供电公司,河北廊坊065000 [3]新能源电力系统国家重点实验室(华北电力大学),河北保定071003 [4]国网冀北电力有限公司怀来县供电分公司,河北怀来075400

出　　处：《陕西电力》2017年第4期50-54,共5页Shanxi Electric Power

基　　金：中央高校基本科研业务费专项资金资助(2016MS91)

摘　　要：三相不平衡源引起的公共连接点(PCC)处母线电压不对称是供电部门关注的主要电能质量问题之一,并以电压(电流)不平衡度作为电能质量考核指标。若想评估新接入负载是否可以接入电网,需要把背景不平衡发射水平和负载不平衡发射水平分离。给出了不平衡发射水平的定义,利用对称分量法将线路阻抗转化为正、负、零序的形式,根据电压、电流、阻抗之间的函数关系列出方程式,求取PCC处的负序电压,并分离出背景和负载的不平衡发射水平。利用仿真分2种情况讨论,并结合实际情况验证了分离方法的可行性。Three phase unbalanced source causing bus voltage asymmetry at the common connection point is one of the main power quality problems in power supply depamnent,and using the voltage （current） unbalance degree as the power quality assessment indicators. To assess whether new access load can be connected to the electricity grid, the background unbalance emission level and load unbalance emission level need to be separated. The defhfition of unbalanc, ed emission level is given, symmetrical component method is used to convert line impedance to the form of positive,negative and zero sequence. According to the function relationship between voltage and current,impedance list equation,the negative sequence voltage at the PCC is resolved, the background and load unbalance the emission level is isolated. The feasibility of the method is proved by the combination of two simulation situations and actual situation.

关 键 词：三相不平衡源 不平衡发射水平 负序电压 

分 类 号：TM714[电气工程—电力系统及自动化]