基于力信号处理的断路器机械特性研究

发布时间：2019-06-24 20:23

【摘要】：断路器是电力系统中重要电力设备,对电网有控制调度作用,又有保护作用。它的可靠性对电力系统的可靠性有重要影响,受到电力系统各部门的关注,对断路器进行检修是保证断路器可靠性的重要途径。目前,状态检修是断路器检修的重要发展方向。状态检修利用传感器技术、计算机技术、信号处理等技术,对断路器进行实时参数监测与处理,判断断路器的实时工作状态及状态趋势,在断路器发生故障前进行检修,做到预防性维修。为了实现断路器状态检修,断路器机械特性的在线监测是非常重要的内容。本文主要对VS1真空断路器机械特性的在线监测进行了系统研究,提出了以力传感器和信号处理技术为基础的准确测量刚分刚合点的方法,并以此为基础实现完整的断路器机械特性的在线监测。本文首先对现有断路器在线监测参数进行了总结分析,明确了断路器机械特性在线监测的重要性,并提出为了实现断路器机械特性的在线监测必须准确测量断路器刚分刚合点。为了解决刚分刚合点的准确测量问题,论文在综合比较基础上提出了通过触头力测量和信号分析处理相结合的基本方案。为了验证力传感器测量刚分刚合点的可行性,论文首先建立了VS1断路器机械结构完整的ADAMS仿真模型,通过对仿真结果的分析,得出了在力传感器信号中包含了断路器刚分刚合点的基本信息,断路器刚分刚合时刻与断路器绝缘拉杆上的力信号突变存在明确的对应关系,为进一步通过信号处理的方式捕获刚分刚合点奠定了重要基础。然后针对断路器触头系统与拉杆结构的特点,设计了专用的力传感器及其配套的信号调理电路。在专用力传感器研制完成的基础上,设计了包括主回路通断测量、力信号测量同时在内的断路器机械特性测试系统,即可实现传统的离线机械特性测量,又可实现在线力信号的测量获得机械特性,同时通过实际力信号与仿真力信号的对比分析,验证了仿真分析的正确性,即现实力信号中,断路器刚分刚合时刻与断路器绝缘拉杆上的力信号突变确实存在明确的对应关系。在实际获取力信号的基础上,为了从力信号中获取刚分刚合时刻,论文在综合分析各种处理方法的基础上,提出了小波包分解与重构的信号处理方案,实现了力信号中刚分刚合时刻的提取计算。通过对力信号处理结果与传统离线测量结果的对比分析发现,以力传感器信号为基础测量的断路器刚分刚合时刻的误差小于0.2ms,更进一步论证以力信号实现断路器机械特性在线测量的可行性。最后,论文设计了完整的以力传感器信号为基础的监测单元的软件和硬件系统,实现了断路器机械特性位移测量、速度测量、开距测量、超行程测量,并实现了断路器控制回路动作时间和控制回路波形的诊断分析,构成了完整、实用的断路器在线监测方案。
[Abstract]:Circuit breaker is an important power equipment in power system, which has both control and protection function for power grid. Its reliability has an important impact on the reliability of the power system and has attracted the attention of all departments of the power system. Maintenance of the circuit breaker is an important way to ensure the reliability of the circuit breaker. At present, condition maintenance is an important development direction of circuit breaker maintenance. Condition maintenance uses sensor technology, computer technology, signal processing and other technologies to monitor and process the real-time parameters of circuit breakers, to judge the real-time working state and state trend of circuit breakers, to carry out maintenance before the failure of circuit breakers, and to achieve preventive maintenance. In order to realize the condition maintenance of circuit breakers, the on-line monitoring of mechanical characteristics of circuit breakers is very important. In this paper, the on-line monitoring of mechanical characteristics of VS1 vacuum circuit breaker is systematically studied, and an accurate method of measuring rigid closing point based on force sensor and signal processing technology is put forward, and the complete on-line monitoring of mechanical characteristics of circuit breaker is realized. In this paper, the existing on-line monitoring parameters of circuit breakers are summarized and analyzed, the importance of on-line monitoring of mechanical characteristics of circuit breakers is clarified, and it is pointed out that in order to realize the on-line monitoring of mechanical characteristics of circuit breakers, it is necessary to accurately measure the rigid closing point of circuit breakers. In order to solve the problem of accurate measurement of rigid closing point, a basic scheme combining contact force measurement and signal analysis and processing is put forward in this paper on the basis of comprehensive comparison. In order to verify the feasibility of measuring the rigid closing point of the force sensor, the ADAMS simulation model of the mechanical structure of the VS1 circuit breaker is established in this paper. Through the analysis of the simulation results, it is obtained that the signal of the force sensor contains the basic information of the rigid closing point of the circuit breaker, and there is a clear corresponding relationship between the rigid closing time of the circuit breaker and the sudden change of the force signal on the insulation pull rod of the circuit breaker. It lays an important foundation for further acquisition of rigid closing point by signal processing. Then, according to the characteristics of circuit breaker contact system and pull rod structure, a special force sensor and its matching signal conditioning circuit are designed. On the basis of the development of the special force sensor, a circuit breaker mechanical characteristic test system, including the main circuit on-off measurement and the force signal measurement at the same time, is designed, which can not only realize the traditional off-line mechanical characteristic measurement, but also realize the on-line force signal measurement to obtain the mechanical characteristics. At the same time, through the comparison and analysis of the actual force signal and the simulated force signal, the correctness of the simulation analysis is verified. There is a clear corresponding relationship between the rigid moment of circuit breaker and the sudden change of force signal on the insulation pull rod of circuit breaker. On the basis of obtaining the force signal, in order to obtain the rigid time from the force signal, based on the comprehensive analysis of various processing methods, the signal processing scheme of wavelet packet decomposition and reconstruction is proposed, and the extraction and calculation of the rigid time of the force signal is realized. Through the comparative analysis of the force signal processing results and the traditional off-line measurement results, it is found that the error of the rigid time of the circuit breaker measured on the basis of the force sensor signal is less than 0.2 Ms, and the feasibility of realizing the on-line measurement of the mechanical characteristics of the circuit breaker with the force signal is further demonstrated. Finally, the software and hardware system of the monitoring unit based on the force sensor signal is designed, which realizes the mechanical characteristic displacement measurement, velocity measurement, open distance measurement and overstroke measurement of the circuit breaker, and realizes the diagnosis and analysis of the action time of the circuit breaker control loop and the waveform of the control loop, which constitutes a complete and practical on-line monitoring scheme of the circuit breaker.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM561

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