Compensation strategy Research of co-phase traction power supply system with Vv transformer under asymmetric grid voltage

In the case of symmetrical grid voltage, the co-phase traction power supply system (CTPSS) with traditional compensation strategy can effectively compensate the negative sequence current and reactive power. However, In the case of asymmetrical grid voltage, it is difficult to achieve compensation with traditional compensation strategy. This paper studied compensating strategy of CTPSS with Vv transformer under asymmetric grid voltage. Firstly, the mathematical model of CTPSS under asymmetric grid voltage is established. Then, the effect of asymmetrical grid voltage on the characteristics of power flow controller (PFC) compensation is analyzed, and a more optimized compensation strategy is proposed. Finally, a simulation model is built to verify the correctness of the compensation strategy, and the results show that the compensation capacity can be saved up to 26.74%.