新疆电网多送出直流输电系统运行特性分析

针对新疆电网±1 100 kV和±800 kV特高压多回直流外送输电系统交互影响的复杂性,基于2015年冬季大负荷运行方式,利用多馈入影响因子（MIIF）、多送出运行短路比（MOSCR）等指标定性分析交直流以及多直流系统之间的影响;在此基础上,利用BPA仿真平台进一步仿真并量化分析了直流故障下系统的稳定性及多直流系统之间相互作用、支援的特性.结果表明;在直流单极闭锁等典型故障下,新疆电网交直流、多送出直流系统之间的交互影响在合理范围内,但双极闭锁等严重工况下存在功角及电压失稳的风险;配套电源支撑是影响电网安全性的关键因素之一;利用多直流的紧急功率支援可提高送端系统稳定性.

Analysis on Operating Characteristics of the Multi-Send HVDC System in Xinjiang Power Grid

This paper applies MIIF（Multi-Infeed Interaction Factor） and MOSCR（Muhi-send Operating Short Circuit Ratio） and other index parameters to analyze the interaction between AC/DC and multiple DC systems of±1000 kV and ±800 kV in Xinjiang Power Grid. Analyzing data is the high load mode of Xinjiang Power Grid in the winter of 2015, on this basis, further simulation is implemented by using BPA simulation software to analyze the characteristics of multiple DC systems interactions and the emergency support with DC power, as well as the system stability with DC faults. Analysis results show that in the typical fault conditions such as single-pole block, the interaction between AC/DC and multiple DC systems is reasonable, but double-pole block and other serious conditions will make the system in a risk of angle and voltage instability. Power supply is one of the key factors to support power grid safety. Using emergency support with DC power can improve the stability of the sending system.