Simulation Method of DC Traction Power Systems with Complex Operation Conditions Based on Unified Chain Model

DC traction power systems are usually adopted in multitrain subway systems with running rails being used as the return conductor for traction current. Multiple traction substations (TSSs) and multiple trains run in parallel with complex operation conditions. Fast and accurate calculation of the dynamic power flow in the system has become an important issue. In this paper, simulation method of DC traction power system with complex operation conditions based on unified chain model is proposed. Operational characteristics of each part in the system are analyzed. Then, the unified chain model of the system with complex operation conditions is established. The equivalent model of reflux system with mixed parameters is established and the calculation method of the dynamic power flow is studied. Simulations are conducted with the parameters in Guangzhou Metro Line 2. Simulations results show that the proposed simulation method can calculate the dynamic power flow effectively.