A Multi-timescale Energy Management Strategy for Advanced Cophase Traction Power Supply System with PV and ES

The advanced cophase traction power supply system (ACTPSS) integrating with photovoltaics (PV) and energy storage (ES) can realize the efficient consumption of regenerative braking energy (RBE) and renewable energy sources. However, the existing single-level energy management strategies for ACTPSS that only focus on the main-station or the sub-station have poor performance in the economy and timeliness. Therefore, a multi-timescale energy management strategy including the minutes-level optimal dispatch for main-station and the seconds-level real-time control for sub-stations is proposed, which can improve the economy and reliability of the ACTPSS with PV and ES simultaneously. In terms of the main-station layer, an min-level optimal dispatch model is established with an objective of minimum operating cost to obtain reference working points of output port converter, PV, and ES in each sub-station. In terms of the sub-station layer, an s-level adaptive working point control strategy based on improved Arctan droop is proposed to ensure the voltage and frequency stability of ACTPSS, while suppressing the PV/RBE power feedback to three-phase power network. Finally, the feasibility and superiority of the proposed multi-timescale energy management strategy are verified by simulations and experiment results.