高压直流输电非解耦线路模型改进算法  

An Improved Calculating Method for the Coupled Line Model of HVDC Transmission

作　　者：徐韬[1] 翁华[1] 徐政[1] 黄莹 黎小林 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027 [2]南方电网技术研究中心,广东省广州市510623

出　　处：《中国电机工程学报》2011年第7期71-76,共6页Proceedings of the CSEE

基　　金："十一五"国家科技支撑计划重大项目(2006BAA02A21)~~

摘　　要：分析同塔双回直流输电工程直流侧谐波电流计算的难点。针对分序算法对耦合极线数存在限制这一问题,采用具有普遍适用性的高压直流输电多相耦合线路非解耦模型算法,并对此模型算法进行改进,通过改变线路导纳矩阵级数展开方法,避免了高频时级数项数增加的问题,在保证精度的前提下简化了计算;同时为确保导纳矩阵级数的收敛性,对线路进行了分段处理。在同等条件下,使用该算法与Matlab计算得到的分段线路导纳矩阵以及PSCAD/EMTDC仿真得到的线路谐波电流值进行对比,结果偏差较小,验证了算法的正确性。In this paper, the difficulty of calculating the DC side harmonic currents in a double circuit on the same tower HVDC system was analyzed. Since the symmetrical component method was very difficult to apply in the double circuit on the same tower HVDC transmission lines, the universally applicative multi-phase coupled transmission line model and its calculating method was adopted, and this method was improved by changing the series expansion form of the transmission line admittance matrix, which avoided the increase in the series terms at high frequency. As a result, the improved method not only reduces the calculation burden but also ensures the calculation accuracy. Furthermore, in order to guarantee the convergence of the admittance matrix series in the frequency range of interest, the studied transmission line was divided into some small sections. Under the same conditions, the calculating result of the admittance matrix of a line section was compared with the result by Matlab, and the line harmonic current result was compared with the result by PSCAD/EMTDC, both show a good consistency, and this verifies the validity of the improved method.

关 键 词：高压直流输电 级数展开 直流线路 谐波电流 

分 类 号：TM74[电气工程—电力系统及自动化]