Impedance Calculations for AT Power Traction Networks with Parallel Connections

The modes of power traction networks are various, such as direct mode, BT (boost transformer) mode and AT (auto-transformer) mode. A new mode of AT power traction networks with parallel connections (PC) is applied on high-speed electrified railways in China. The impedance of normal AT power traction networks was analyzed in many documents with some methods, such as generalized method of symmetrical components, equivalent circuit method. AT power traction networks with parallel connections is a new power supply mode. According to the characteristic of this power supply mode, the impedance was analyzed and calculated in this thesis based on generalized method of symmetrical components (GMSC). The impedance characteristic was shown with graph in briefly based on the parameters of one AT power traction networks. The method is simple and is a good tool to analyze AT power traction networks with parallel connections. At last, suggestion about relay protection and fault location for this power supply mode is put forward.