Solution of DC Railway Traction Power Flow Systems Including Limited Network Receptivity
This paper presents a new procedure based on a backward/forward sweep (BFS) speed direction for solving power flows in weakly meshed dc traction networks is presented. The proposed technique is able to consider the trains as nonlinear and non-smooth (no differentiable) voltage-dependent loads or generators. This feature permits the inclusion of the trains' over current protection and the squeeze control. With the use of the mentioned controls, the conventional power flow problem becomes a voltage constrained power flow problem, and the interaction between the trains and the network can be accurately modeled. However, the train control induces a highly no smooth voltage-dependent load characteristic, causing convergence problems in most of the derivative-based. The proposed method is faster, more robust, and more stable than the derivative-based ones.