A Framework-Compatible Hierarchical Railway Power Regulation Strategy with the Integration of Energy Storage-embedded Railway Power Flow Controller

Intelligent power regulation is a prominent feature of smart railway power systems (RPSs). To achieve this target, the energy storage-embedded railway power flow controller (ES-RPFC) can be adopted, as it provides an effective solution for demand management (DM) and power quality (PQ) improvement. While in practice, those two functions of ES-RPFC are often implemented in two native less-compatible frameworks, and the converter rating, which significantly influences the whole system’s investment, is seldom considered. These deficiencies diminish the global performance of the whole system. To address them, a novel power regulation strategy is proposed. In this strategy, 1) a unified analytic mathematical framework is first proposed for ES-RPFC’s compatibility improvement on both DM and PQ control, which is also beneficial for calculation efficiency improvement; 2) a hierarchical control strategy is developed upon the framework in 1). This strategy enables compatible implementation of DM and PQ control with minimized BTBC rating while making the RPS exhibit satisfactory grid-connection performance. A comprehensive measured data-based performance evaluation for the proposal is carried out, and the results show that compared with the traditional method, the BTBC rating is reduced by almost 43% in the studied case. Moreover, the proposal’s real-time implementation feasibility is verified by hardware-in-the-loop tests.