继电保护系统隐性故障在线监视与诊断技术

发布时间：2018-05-09 10:05

本文选题：继电保护系统 + 隐性故障　；参考：《天津大学》2014年硕士论文

【摘要】：随着电力系统规模的不断扩大,对其安全、可靠和稳定运行的要求也相应提高,但是,由于受系统自身因素以及外部扰动等的影响,继电保护系统作为保障电网安全的第一道防线所带来的问题也越来越突出,对电网稳定运行和社会发展都造成了严重影响。据调查显示,继电保护系统隐性故障成为引起保护不正确动作以及推动连锁事故发生的一个重要原因。因此,对隐性故障的特征挖掘、辨识以及预警与预防技术的研究成为一个重大而迫切的课题,这对于保障电力系统的安全可靠运行有着极为重要的意义。本文通过搜阅大量的相关文献资料,首先对隐性故障的基本概念、产生原因和故障表现形式等进行了简要介绍,在此基础上总结了隐性故障现有的研究方法,探究了隐性故障的常用概率模型、脆弱性区域与脆弱性指数、风险评估以及监测与控制方法。通过深入挖掘隐性故障的产生原因,并结合国内外发生的多起大停电事故,对隐性故障的类型进行了系统的划分,并对继电保护硬件设备和元件隐性故障进行了特征挖掘与辨识。其中,主要就断路器操作机构和直流操作回路存在的问题进行了具体分析,并提出了相应的在线监视与故障诊断方法。通过对高压断路器二次回路及操作机构工作特性进行分析,指出其分合闸线圈电流信号中蕴含的大量断路器机械状态信息,并提出一种分合闸线圈电流与最小二乘支持向量机算法结合的断路器隐性故障在线诊断方法,该方法可以准确地识别断路器二次回路及操作机构多种隐性故障类型,为断路器隐性故障定位和状态检修提供了依据。通过分析直流操作回路的工作原理和特点,并结合引起继电保护隐性故障的主要问题,提出了一种直流操作回路在线监视与预警方法。该方法通过在线监测直流操作回路流过的电流,实现跳、合闸回路完整性的同时监视;利用时间继电器在线监视跳、合闸回路的工作状况,实现跳、合闸回路元件的保护。最后,利用线路保护操作箱和断路器装置,对所提出的监视与预警方法进行了实验验证。
[Abstract]:With the continuous expansion of power system scale, the requirements of safe, reliable and stable operation of power system are raised accordingly. However, due to the influence of the system itself and external disturbances, As the first line of defense to ensure the security of the power grid, the relay protection system brings more and more serious problems, which has a serious impact on the stable operation of the power grid and the social development. According to the investigation, the hidden fault of relay protection system has become an important reason to cause incorrect action of protection and promote the occurrence of chain accidents. Therefore, the research of hidden fault feature mining, identification, early warning and prevention technology has become a major and urgent issue, which is of great significance to ensure the safe and reliable operation of power system. In this paper, the basic concepts, causes and forms of hidden faults are briefly introduced, and the existing research methods of hidden faults are summarized. Probabilistic models of hidden faults, vulnerability region and vulnerability index, risk assessment, monitoring and control methods are explored. By digging into the causes of hidden faults and combining with many power outages at home and abroad, the types of hidden faults are systematically divided. The hidden faults of hardware and components of relay protection are mined and identified. The problems existing in the circuit breaker operating mechanism and DC circuit are analyzed, and the corresponding on-line monitoring and fault diagnosis methods are put forward. By analyzing the working characteristics of the secondary circuit and the operating mechanism of the high voltage circuit breaker, it is pointed out that a large amount of mechanical state information of the circuit breaker is contained in the current signal of the switchover coil. An online fault diagnosis method for circuit breakers based on the combination of closing coil current and least square support vector machine (LS-SVM) is proposed. This method can accurately identify the secondary circuit of circuit breaker and various hidden fault types of operating mechanism. It provides basis for hidden fault location and condition maintenance of circuit breaker. By analyzing the working principle and characteristics of DC operation circuit and combining with the main problems that cause hidden fault of relay protection, an on-line monitoring and warning method of DC operation circuit is proposed. By on-line monitoring the current flowing through the DC operating circuit, the method can realize the jump and the integrity of the closing circuit at the same time, and use the time relay to on-line monitor the jump and the working condition of the closing circuit to realize the protection of the trip and closing circuit elements. Finally, the proposed monitoring and early warning method is verified by using line protection operation box and circuit breaker device.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM77

【参考文献】