节点文献
永磁机构真空断路器运动特性状态评估方法研究
The Study on State Evaluation Method of Vacuum Circuit Breaker Motion Characteristic with Permanent Magnetic Operating Mechanism
【作者】 李斌;
【导师】 林莘;
【作者基本信息】 沈阳工业大学 , 电机与电器, 2013, 博士
【摘要】 随着我国智能电网的建设和电力设备状态检修技术的需求,对高压真空断路器的智能化和运行可靠性的要求越来越高,全面科学地评估断路器的运行状态,能够为制造企业提供改进方向、也可以为电力运行部门制定检修策略提供依据。本文为解决真空断路器状态评估方法中存在的单一信号诊断、评估结果准确性不高、评估判据缺乏理论依据和数据来源不可靠等问题,以ZW45-12型单稳态永磁操作机构真空断路器为研究对象,从状态评估、故障诊断和信号处理等方法以及实际应用的角度进行深入的研究,主要的研究内容和成果如下:(1)基于多智能体理论,提出了断路器运动特性多智能体状态评估方法模型。设计了该模型的体系结构和评估过程,研究了区分操作机构电气特性故障和断路器机械特性故障的数学模型、基于断路器机械振动信号的相关向量机诊断方法和基于断路器触头行程信号的可拓状态评估方法,并给出了先评估后诊断的评估策略。该方法可评估出断路器运动特性当前的状态和变化趋势,诊断出具体影响状态的原因,同时也克服了个别传感器失效对评估结果的影响。(2)提出了断路器触头行程信号和操作机构电流信号的特征值提取方法;研究了断路器机械振动信号的短时傅里叶变换、小波包能量熵和希尔伯特-黄变换三种特征提取方法,并采用模糊C聚类分析算法比较三种方法的性能,确定了机械振动特征提取智能体推理机模型;研究了断路器上述三类信号特征数据稳定性与断路器故障机理,证明了断路器数据采集系统的可靠性和数据特征提取方法的可行性,得出了断路器运动特性不同状态下各信号特征值的变化规律。(3)采用软件组合技术构建了断路器运动特性虚拟样机模型,并对模型内的静态保持力、系统反力、等效质量和接触器电弧进行了计算,确定了具体的建模参数。根据实测的信号数据,校验了所建立的虚拟样机模型的准确性。通对实验数据和虚拟样机模型仿真数据综合分析,计算出断路器触头行程信号参数判据,并建立了操作机构电流信号故障知识库。(4)本文设计与研发了断路器数据采集系统和多智能体评估系统。给出了系统的软硬件设计和实现方案,保证了数据采集系统的可靠性;采集和评估系统均已申请国家发明专利;通过对断路器正常状态、操作机构控制回路电阻增大、分闸弹簧单根脱落、操作及传动机构卡涩和行程传感器故障等五种状态试验,验证了所提出的断路器运动特性状态评估方法的准确性和评估系统的有效性。
【Abstract】 With the construction of smart grid in China and the needs of power equipmentcondition based maintenance technology, it increasingly requests for intelligent andreliability of high voltage vacuum circuit breaker. It can provide direction ofimprovement for manufacturing firms and basis of drawing up maintenance strategy inelectric power department by evaluating operating states of circuit breaker scientificallyand roundly.This paper works on solving the problems exist in state evaluation method ofvacuum circuit breaker, such as single signal diagnosis, low accuracy of evaluate results,lack of theoretical basis for the evaluation criterion and data unreliable of source. In thepaper, it has taken ZW45-12vacuum circuit breaker with mono-stable permanentmagnetic mechanism as an example, it has intense study on methods of state evaluation,fault diagnosis and signal processing, as well as on practical application, and the mainresearch content and result are as follows:It has been proposed the state evaluation method of circuit breaker motioncharacteristic based on multi-agent, designed the architecture in multi-agent system andevaluation process of this method; researched on mathematical model for distinguishbetween operating mechanism electrical characteristic fault and circuit breakermechanical characteristic fault. According to mechanical vibration signal, it has beenproposed the diagnosis method based on relevance vector machine theory for circuitbreaker mechanical characteristic; According to contact displacement signal, it has beenproposed the evaluation method based on extension theory for circuit breaker motioncharacteristic; and proposed the evaluation strategies of evaluation before diagnosis. Themethod can evaluation the current state and trends of the circuit breaker motion characteristic, work out the specific impact condition, overcome the influence ofindividual sensor failure on the evaluation results.It has researched on feature extraction method of contact displacement signal,operating mechanism current signal of circuit breaker; According to mechanical vibrationsignal of circuit breaker, it has researched on three time-frequency domain signalprocessing methods of the short time Fourier transform, wavelet packet energy entropy,Hilbert-Huang transform, adopting the fuzzy C clustering analysis algorithm to compareperformance of three kinds of feature extraction methods, in order to propose themathematical model of feature extraction agent reasoning machine based on mechanicalvibration signal; It has researched on the stability of feature data, and failure mechanismof circuit breaker, it has been proved that the reliability of data acquisition system and thefeasibility of feature extraction method, and obtained the change rule of each motioncharacteristic signal eigenvalue under different status of circuit breaker.It has been constructed the virtual prototype model of circuit breaker motioncharacteristic through the software integrated technique, calculated static retention,system reaction, equivalent mass and contact arc of the this model, signed the concretemodeling parameters. According to the measured signal data, it has checked the accuracyof the virtual prototype model established. Through comprehensive analysis of simulationdata of virtual prototype model and experimental data, it has calculated the parameterscriterion of circuit breaker contact displacement signal, and established the faultknowledge base of operating mechanism current signal.It has been designed and explored data acquisition system and evaluation system ofcircuit breaker based on multi-agent; proposed the design and implementation scheme ofsystem hardware and software, and ensured the reliability of the data acquisition system.Acquisition and evaluation system have been applied for national invention patent.Through experiments in five conditions: normal condition of circuit breaker, resistanceincreases of operating mechanism control loop, opening spring single take off,mechanism unsmooth of operating and transmission, and displacement sensor fault, it has been tested and verified that the accuracy of state evaluation method and theeffectiveness of evaluation system of circuit breaker motion characteristic.
【Key words】 permanent magnetic operating mechanism; vacuum circuit breaker; state evaluation; virtual prototype; fault diagnosis;