单相电源法测量单回不对称线路阻抗参数的误差分析与改善措施  

Error analysis and improvement measures of single-phase power supply method to measure the impedance parameters of single-circuit asymmetric line

作　　者：董清[1] 邵鹏程 Dong Qing;Shao Pengcheng(School of Electrical and Electronic Engineering,North China Electric Power University,Baoding 071003,Hebei,China)

机构地区：[1]华北电力大学电气与电子工程学院,河北保定071003

出　　处：《电测与仪表》2018年第15期15-19,30,共6页Electrical Measurement & Instrumentation

摘　　要：随着高压输电线路数量的日益增多,因此大多数线路都采用不换位的架设方式,该文对单回不换位线路三相阻抗参数测量时所采用的单相电源测量方法产生误差的原因进行了分析,由于测量电路考虑了大地电阻对阻抗参数的影响,因此提出了一种新的测量大地电阻的方法。在进行单回不换位线路三相阻抗参数的计算时,电流矩阵的求逆运算给三相阻抗参数的计算带来了很大的误差,并且推导出了误差项的表达式,为了减小误差,文中提出了采用双端测量方法测量出三相线路首、末端的电压和电流,最后以一条500 k V的单回不换位线路为例,利用首、末端得到的三相电压、电流量在进行单回不换位线路三相阻抗参数的计算时可以减小误差,验证了文中方法的可行性。With the increasing number of high-voltage transmission lines,most of the lines are installed in a non-transposition manner. The reason for the error caused by the single-phase power measurement method used for measuring the threephase impedance parameters of single-circuit non-replacement lines is incorrect. Since the measurement circuit takes into account the influence of the earth resistance on the impedance parameters,and a new method for measuring earth resistance is analyzed and proposed in this paper. When calculating the three-phase impedance parameters of a single-circuit non-commutation line,the calculation of the three-phase impedance parameters is brought about the large error by the inverse operation of the current matrix,and the expression of the error term is derived. In order to reduce the error,this paper proposed the use of double-end measurement method to measure the voltage and current at the beginning and end of the three-phase line,and finally takes a single 500 k V single back does not change for the bit line as example,it shows that the three-phase voltage and current obtained by the first and the end can reduce the error when calculating the threephase impedance parameters of the single-circuit non-commutated line,and the feasibility of the method is verified.

关 键 词：输电线路 不换位 三相阻抗 双端测量 误差分析 矩阵求逆 

分 类 号：TM751[电气工程—电力系统及自动化]