  The flexible traction power supply system (FTPSS) eliminates the neutral zone
but leads to increased complexity in power flow coordinated control and power
mismatch. To address these challenges, the methodology for power dispatch (PD)
based on traction station clusters (TSCs) in FTPSS is proposed, in which each
TSC with a consistent structure performs independent local phase angle control.
First, to simplify the PD problem of TSCs, the system is transformed into an
equivalent model with constant topology, resulting in it can be solved by
univariate numerical optimization with higher computational performance. Next,
the calculation method of the feasible phase angle domain under strict and
relaxed power circulation constraints are described, respectively, which
ensures that power circulation can be either eliminated or precisely
controlled. Finally, the PD method with three unique modes for uncertain train
loads is introduced to enhance power flow flexibility: specified power
distribution coefficients between traction substations (TSs), constant output
power of TSs, and maximum consumption of renewable resources within TSs. In the
experimental section, the performance of the TSC methodology for PD is verified
through detailed train operation scenarios.
