Application of SSSC to improve the transmission capability of Tianjin 220kV power grid

After introducing the present operation situation of Tianjin power grid, this paper reveals the causes of the limited transmission capacity of total cross-sectional area and the circuitous power flow of the double lines in Tianjin. The development and state-of-art of static synchronous series compensator (SSSC) technology are covered in this paper along with the lines running plan of Tianjin power grid in future. A variety of measures to deal with the limited section of transmission capacity and roundabout power flow are proposed and compared, which draws to a conclusion that SSSC is the optimal solution for improving power grid structure and adjusting regional power flow. Therefore a detailed application scheme of SSSC is proposed subsequently for the 220kV power grid in Tianjin. The electricity compensation amount of SSSC demands in Tianjin area is analyzed theoretically, and three alternative capacity of SSSC under steady state control are proposed. The optimized capacity and location scheme of SSSC are derived with equivalent data of Tianjin power grid, and are presented in a transmission capacity effect table. Considering the N-1 transient stability limit and the line rated current constraints, the compensation capacity and the capacity curve of the cross section are given, which provides the basis for the SSSC scheme of various operation modes in Tianjin power grid. Finally, the validity and rationality of the SSSC application in Tianjin 220kV power grid are verified via the power flow data of BPA.