A New Decoupling Method for Double-Circuit Transmission Lines with Asymmetrical Parameters

作者：Fan, Chunju^*; Xu, Kan; Liu, Qi

来源：IEEJ Transactions on Electrical and Electronic Engineering, 2017, 12(2): 161-168.

DOI：10.1002/tee.22362

• asymmetrical parameters
• double-circuit lines
• decoupling
• short-circuit calculation
• partial coupled line

The six-sequence component method is widely used in short-circuit calculation of double-circuit lines. However, this method can be used to decouple only two parallel transmission lines whose parameters are exactly the same. In this paper, a new sequence component method is introduced to deal with the lines whose parameters are not exactly the same. Mutual impedances between phases of the same line are decoupled first, and then the zero-sequence mutual impedances between different lines are decoupled. Six new independent components are obtained after decoupling. System impedances are modified based on the relationship between voltages and currents of the new sequence components and the traditional sequence components. According to the boundary conditions of the faults, the characteristics of new sequence components are studied, and the corresponding sequence networks are discussed. According to the combined sequence network, new sequence currents can be calculated, and the phase currents can be obtained easily from the new sequence currents by a transformation matrix. PSCAD simulation results demonstrate that the short-circuit calculation method proposed in this paper is appropriate and practical to deal with the two parallel transmission lines with different parameters and partially coupled transmission lines.

• 出版日期2017-3
• 单位上海交通大学