Considering reactive power coordinated control of hybrid multi‐infeed HVDC system research into emergency DC power support

Abstract

According to the characteristics of line-commutated converter high-voltage direct current (LCC-HVDC) and voltage source converter high-voltage direct current (VSC-HVDC), respective additional emergency DC power support (EDCPS) controllers are designed, and a coordinated control strategy based on a hybrid multi-infeed HVDC system for EDCPS is proposed. Considering the differences in system recovery performance between LCC-HVDC and VSC-HVDC in providing EDCPS, the emergency power support priority issues and power allocation schemes for LCC-HVDC and VSC-HVDC are discussed in detail. To maintain the stability of the receiving-end AC system during boosting power process and to ensure the active power is raised to the specified value, this study also designs an additional reactive power controller that can make full use of the ability of VSC-HVDC to support the reactive power of the AC system. Finally, a hybrid three-infeed HVDC system consists of two parallel LCC-HVDCs and one VSC-HVDC is built on PSCAD/EMTDC and simulated. The effectiveness of the proposed approach is verified based on this hybrid three-infeed HVDC system.