The comparison and analysis of lumped parameter equivalent circuits of transmission line

Based on the frequency characteristics analysis, the feature and scope of lumped parameters circuits are presented in this paper, which can be as the reference of equivalent circuit selection. Firstly the Γ section equivacircuit was introduced as the equivalent of transmission line and its validity was proved. The frequency characteristics of lumped parameters circuits are analyzed and compared with the distributed parameters circuit. From characteristic analysis, the effective frequency band that the lumped parameters circuit can be taken as the equivalent of transmission line was obtained. Considering effective frequency band and model complexity, the selection principle for application is proposed. The research results showed that Γ section has the best approximation and Γ section has the simplest model equation. The proper selection of equivalent circuit can significantly increase the convenience and effectiveness for power system calculation.