特高压直流双极区直流保护系统可靠性研究

双极区直流保护系统误动将导致双极强迫停运的严重后果，提高双极直流保护系统的可靠性是重要的研究内容。分析了特高压直流双极区直流保护系统的两种配置策略，建立了各配置策略的可靠性分析模型，推导出其可靠性公式和可靠性曲线图，结果表明集成到极保护系统的三重化配置策略具有更高的可靠性。阐述了双极区直流保护功能和动作策略，分析了双极中性母线差动保护、NBSF顺控逻辑和金属回线使能信号等关键技术问题并提出了优化方案。目前，部分优化方案已在多个特高压直流输电系统中实施，效果良好。最新的优化方案将在新建工程中实施。

Reliability research for UHVDC bipolar area DC protection system

Bipolar area DC protection system malfunction will lead to serious consequences bipolar forced block, so it is important to improve bipolar DC protection system reliability. This paper analyzes two configuration strategies of UHVDC bipolar area DC protection system, establishes a reliability model of the configuration strategy, and derives its reliability formula and reliability graphs. The results show that the protection system integrated into a triple of configuring cubicles has greater reliability. It describes the bipolar protection functions and action strategies, analyzes bipolar neutral bus differential protection, NBSF sequence logic and metal loops enable signal and other key technical problems and then proposes the optimization strategy. At present, part of the optimization program is implemented in multiple UHVDC power transmission system, and then system operates well after adopting the measure. The latest optimization program will be implemented in the new project.