变应力条件下漏电断路器可靠性的实时评价及预测

With the improvement of electricity supply requirements, the reliability of switch apparatus is becoming more and more important. This project focuses on residual current circuit breaker (RCCB) and conducts the research about real-time evaluation and prediction of RCCB’s reliability under variable stress, which has important theoretical significance and application prospects..Firstly，the operational characteristics and failure evolution mechanism of RCCB is researched, and the mathematical model of RCCB’s reliability is established. The method innovation of reliability research from separated failure mode to combined failure mode can be achieved. Secondly, the accumulative effect and model of reliability for RCCB under variable stress is studied, and the real-time varied characteristics of RCCB’s reliability is analyzed. The theoretical innovation of reliability research from macroscopic static mode to real-time dynamic mode can be realized. Thirdly, the degeneration mechanism and model of breaking performance and protection performance of RCCB under various stress is researched, and the relationship between characteristic parameters and reliability of RCCB is analyzed, while the real-time evaluation and prediction model of reliability based on operating status is built. The theoretical innovation of reliability research from statistical analysis mode based on failure data to status monitoring mode based on performance degradation can be achieved. Finally, the method to monitor operation parameters and extract characteristic parameters of RCCB is studied, while the experimental platform is built. The test data analyzation and feature recognition are conducted to perfect the model of reliability evaluation and prediction. The aforementioned research lays the foundation for operation and maintenance strategy formulation and reliability improvement of power supply system.

随着供用电要求的提高，开关电器可靠性越来越重要。本项目以漏电断路器为对象，研究变应力条件下其可靠性实时评价和预测中存在的科学问题，因此具有重要的理论意义和应用前景。.研究漏电断路器服役行为特征及其失效演化机理，建立可靠性数学模型，实现从分立失效模式到联合失效模式下可靠性研究的方法创新；研究变应力下漏电断路器可靠性的叠加效应和模型，分析变应力下其可靠性的实时变化特征，实现从宏观静态可靠性到实时动态可靠性研究的理论创新；研究漏电断路器在各种应力下开断性能与保护性能的退化机理和模型，分析其特征参量与可靠性间的关系，建立基于运行状态的可靠性实时评价和预测模型，实现从基于失效数据的统计可靠性到基于性能退化的状态可靠性研究的理论创新；研究漏电断路器运行参量监测和特征参量抽取方法，搭建试验监测平台，进行试验数据分析和特征识别，完善可靠性评价与预测模型，为供用电系统的运维策略制订和可靠性水平提高奠定基础。

本项目以漏电断路器为研究对象，解决变应力条件下其可靠性的评价及寿命预测问题。主要研究工作和创新如下。.1研究了漏电断路器关键特征参数与负荷应力参数检测技术和方法，研制出基于计算机控制和高速采集技术专用电寿命试验装置，实现了试验过程中试品主回路电压电流动态变化过程逐次实时记录。提出了模拟量输入采样非同步采样误差和多路模拟量采样误差的解决方法，并确定了反映漏电断路器性能变化的特征参数，即电弧电量、焦耳积分、燃弧能量、触头质量损失。.2建立了漏电断路器触头电磨损模型，并提出基于触头磨损率的剩余电寿命的预测方法。电弧侵蚀因子反映触头质量损失和燃弧特征量的关系，在一定电流范围内，电弧侵蚀机理不变，其电弧侵蚀因子函数相同；当电流范围变化比较大时，电弧对触头的侵蚀机理发生改变，其电弧侵蚀因子函数不同。在电流较小情况下，漏电断路器的触头受到的电弧侵蚀较轻，其服役时间取决于机械寿命；在电流较大时触头磨损程度增加，漏电断路器触头发生粘连失效；而在电流很大时电弧燃烧会引起其他部件的关联失效。.3将累积触头磨损量作为退化特征量，用Wiener过程描述电性能退化过程，用指数分布描述偶然失效，建立基于竞争失效的漏电断路器可靠性模型并进行仿真分析。退化失效模式与偶然失效模式下的中位寿命比值P介于0.3和3.3之间时应采用基于竞争失效的可靠性模型建模方法评估其可靠性，而P小于等于0.3时可以采用基于退化失效的建模方法，P大于等于3.3时可以采用基于偶然失效的建模方法。.4构建了漏电保护模块的仿真模型，并采用灵敏度分析方法进行漏电保护模块关键元器件的辨识，可以减少漏电保护模块可靠性分析工作量，且可靠度评估误差在可接受范围内。提出了一种Monte-Carlo仿真和参数灵敏度分析相结合的漏电保护模块可靠度评估方法，解决了复杂电路数值方法求解可靠度困难的问题，为漏电保护模块的可靠性设计提供了参考。