The multi-infeed HVDC systems are closely coupled between the inverter stations, which is easy to cause concurrent commutation failures (CFs). In this paper, the electrical distance is adjusted by the installation of series reactors (SRs) to reduce the multi-infeed interaction factor (MIIF). At the same time, reactive power (VAR) compensators are added at some buses with SRs installed to control the voltage drop and power flow of the system. Finally, a mathematical model for the SRs and VAR compensators installation is established, and the particle swarm optimization (PSO) algorithm is used to optimize the installation. The simulation results of the power grid show that the optimized installation can inhibit the problem of concurrent CFs.

multi-infeed HVDC system,concurrent commutation failure,the multi-infeed interaction factor (MIIF),particle swarm optimization