Negative Sequence Compensation Method for High-Speed Railway With Integrated Photovoltaic Generation System

The serious negative sequence (NS) issues and energy shortage problems are aroused by the single-phase 25-kV traction power supply system (TPSS) of high-speed railways. To achieve NS compensation and alleviation of energy demand, a TPSS with an integrated PV generation system is proposed. According to the structural characteristics of the TPSS and the PV system, a special topology and an NS compensation method are presented. Moreover, taking the NS control as the primary goal, three operation modes are classified by considering the load conditions of the TPSS and the output state of the PV system. After that, a coordinated control system with a central controller and multiple local controllers is proposed. The central controller can realize the flexible selection of operation modes and calculate the reference power. Meanwhile, the local controllers achieve the accurate tracking of the reference current and the stability of the DC link voltage by switching the control modes. Finally, the feasibility and effectiveness of the proposed system and the NS compensation method are verified by simulations.