Research on the Optimization of Return Line Laying Mode of 500 kV Pumped Storage Power Station

In order to solve the problem of high circulating current in the return line of a 500kV pumped storage power station for a long time, this paper puts forward the optimal laying method of the return line shared by multiple circuits, uses the ATP-EMTP numerical simulation software to establish the corresponding model, and studies the changes of the return line current and the sheath voltage under the normal conditions of the line before and after the transformation and under the single-phase short circuit fault. The results show that the common return line can effectively reduce the current level of the return line and reduce the sheath voltage during the fault, which proves the feasibility of the optimization method. The optimization method proposed in this paper can minimize the workload of line transformation, improve the reliability of line operation and reduce the investment cost, which can provide reference for the actual transformation.