Analysis on the Interaction of AC/DC Systems Based on Multi-Infeed Q Effective Short Circuit Ratio

摘要

Until 2015, Ultra-high voltage DC delivery channels of Southwestern Power Grid will be increased to four. The more complex structure results in higher difficulty to analyze it. Considering the reactive power loss of converter stations, this paper defines multi-infeed Q effective short circuit ratio and presents the criteria of weak system. Taking Southwest China Power Grid under both flood season and large power flow in the year of 2015 for example, in output HVDC project, the paper analyzes the interaction using multi-infeed Q effective short circuit ratio. The simulation results indicates the improved index to evaluate the interaction of multi DC transmission system more reasonable, as well as network planning with more accurate guidance.