Two step method for rail potential rise analysis in DC traction power supply system

초록

An algorithm for analyzing the rail potentials in a DC traction power supply system is proposed. The distinctive feature of this algorithm is that it uses the node voltage method twice in the rail potential analysis. To calculate the rail potentials, the leakage resistance of the running rail must be included in the equivalent network, which makes it difficult to apply the node voltage method. The mesh current method has the drawback that the initial mesh currents are difficult to estimate, which is necessary for an iterative network solution. In this algorithm, the rail potentials are obtained by applying the node voltage method twice. In the first stage, the injection currents to the negative rail are obtained from a load-flow study. In the next stage, a network consisting of the negative rail and the injection currents is constructed. The leakage resistance to ground is added to the network, and the rail potentials of the network are analyzed. A computer load flow analysis software package was developed to verify the validity of the algorithm. The results from the software are compared with the EMTP-RV circuit analysis results, and the results are nearly identical.