基于微扰法的不换位输电线路相模变换

摘要

Traditional symmetrical component method only works under the condition of symmetrical parameters of transposed transmission lines. The error can't be ignored if the transmission lines are un-transposed single-circuit transmission lines. The modal analysis can be used for better results. The key of the modal analysis is to get a phase-mode transformation matrix. This paper considers the effect of the existence of the earth wire and uses perturbation theory to get phase mode transformation matrix of different precisions by building a perturbation made by un-transpose. Applying the obtained matrix to the theory of modal analysis, it finds that the calculated results have small error compared with the real results, verifying the feasibility of the method.%传统的对称分量法适用于理想换位的三相对称输电线路,对于不对称程度较大的不换位单回输电线路,其结果误差较大.为获得更精确的结果,采用模分量法,该方法的关键是求解相模变换矩阵.考虑了架空地线对不换位线路阻抗矩阵的影响,并运用微扰理论,通过构造因不换位造成的阻抗矩阵微扰量,可以求解出不同精度的相模变换矩阵.将求得的变换矩阵用于模分量理论进行故障分析,所得的计算结果与实际结果相比误差很小,验证了该方法的可行性.