Research on control method of two single-phase B2B STATCOM in traction system

A novel power conditioner based on two single-phase B2B STATCOM, which is used for active power accommodation in electric railway, is proposed in this paper. It could achieve bi-directional energy transmission between two feed lines so as to balance the load of the two lines, which could not only decrease the negative sequence current significantly, but also improve the capability of railway transportation. Meanwhile, the two converters could also compensate reactive power of their own feed lines independently. A hierarchical control structure is adopted in the novel power conditioner, which contains system-level and converter-level control. Power transfer between two feed lines is given by mathematical derivation firstly, and simulation is carried out to verify the effectiveness of the equipment and the control algorithm.