Analysis of dual-infeed HVDC with LCC inverter and VSC rectifier

A dual-infeed HVDC with LCC inverter and VSC rectifier at the same busbar is investigated. The impact of VSC rectifier on LCC inverter is quantified by the “Apparent Increase in Short Circuit Ratio” or AISCR index. Then, steady state and transient aspects, such as the maximum available power (MAP), temporary over-voltage (TOV), "Commutation Failure Immunity Index" (CFII), and fault recovery performance are considered in the system performance analysis. The results show that, the VSC rectifier has the ability to improve the maximum available power, regulate the ac voltage, and enhance commutation failure immunity of LCC inverter. Moreover, compared with the dual-infeed HVDC with VSC and LCC both inverters, the VSC rectifier provides more contribution to the performance improvement of LCC converter.