MIDC system voltage support capability evaluation index with renewable energy sources

Renewable energy sources (RES) connected to the receiving end of the multi-infeed HVDC (MIDC) system will affect the node voltage support capability, which in turn affects the voltage stability of the power grid. To reasonably evaluate the voltage support capability of RES integrated MIDC systems, firstly, the structural characteristics of the MIDC system and the amplitude and phase characteristics of different types of RES are analyzed. Secondly, based on the traditional short circuit ratio index combined with the RES amplitude and phase characteristics, the multi-infeed transient short circuit ratio (MITSCR) is defined, and the method of analyzing the voltage support capability of MIDC system is proposed. Finally, time-domain simulation analysis is carried out using PSACD/EMTDC, and the results show that the MITSCR can effectively characterize the node voltage support capability.