An Analysis on the VSC-HVDC Contribution for the Static Voltage Stability Margin and Effective Short Circuit Ratio Enhancement in Hybrid Multi-Infeed HVDC Systems

Over the years, high voltage transmission of large energy blocks over long distances has widely developed from Line Commutated Converter (LCC) technology. However, continuous expansion AC network and increase in renewable penetration leads to weakening Electric Power Systems (EPS), causing operational problems for LCC-HVDC. This paper evaluates degree contribution VSC-HVDC on LCC-HVDC dynamic performance when infeed is a hybrid multi-infeed HVDC system. Through steady-state mathematical framework, new concept Hybrid Voltage Interaction Factor (hPVIF) proposed assess transient stability improvement LCC. Additionally, this article introduces two key contributions hPVIF: complementary Improved Commutation Failure Immunity Index (iCFII), as measure effective short circuit enhancement, well apparent line length, which emulates lengths adjusting power dispatch VSC-HVDC. PSCAD/EMTDCTM time-domain simulations are performed indexes, Matlab® software will be used assist operations.