Design method for strengthening high-proportion renewable energy regional power grid using VSC-HVDC technology

Abstract

This paper proposes a general design method for strengthening regional power grids with high proportion of renewable energy using voltage source converter based high voltage direct current (VSC-HVDC) technology. First, three main security and stability problems of regional power grids with high proportion of renewable energy are pointed out, which implies the necessity of the VSC-HVDC reinforcement scheme. Second, two VSC-HVDC reinforcement schemes are designed to strengthen a real high-proportion renewable energy regional power grid in China, with emphases on the determination of location and capacity of VSC stations. Third, three evaluation indexes that related to the security and stability of power grids are put forward, namely line load rate, bus voltage level and system strength of the VSC-connected terminal. Finally, the two alternative reinforcement schemes are analyzed in detail. The results show that, the two VSC-HVDC schemes can well solve the line overload problem of electromagnetic loop networks with high generation of renewable energy, and can effectively increase the voltage level of the system during the fault period. After a comprehensive evaluation, scheme 2 is slightly superior to scheme 1.