Transient Overvoltage Analysis of Traction Power Supply System with Neutral Sections in China High-Speed Railway Using a State-Space Model

This study proposes a complete state-space model of 2 × 25 kV traction power supply system with neutral sections in China high-speed railway where the catenary system is divided into several sections insulated with each other and is connected by neutral sections. First, the system is modularized by a neutral section module, a source module, autotransformer (AT) modules, series modules, and parallel modules which are represented with differential equations. Then the state-space model is built by means of slicing catenary system and combining with those modules. By calculating this proposed model, the transient processes of the electric train auto-passing trough the neutral section are analyzed. Transient overvoltages occurred due to high-frequency oscillations as the circuit topology changing in each process.