基于相位法配电线路故障定位系统的研究

发布时间：2018-12-12 23:37

【摘要】：为保障工业生产以及人民生活的正常进行,当配电网突发故障时,电力工作人员应及时查明故障原因,确定故障点位置,并在第一时间进行抢修将故障排除。为快速的帮助维修人员找到接地故障点,采取基于相位法的配电网单相接地故障在线定位的方式。由于故障发生时,故障点前后位置的零序电流的相位将由同相变为反相,因此本设计主要思路为,在线路端采用本设计进行信息采集,其中包括三相电流采集及三相电流相位值的计算,将电流数值相叠加即为零序电流,并采用无线传输方式将数据传输至总机,在总机处对具体故障点位置进行判断。相位法在进行故障定位上是常采用的定位方式。本文通过对比多种判别方法的优缺点,最后确定采用相位法,采用Matlab软件中的Simulink模块搭建传输线路,并将线路中可能出现的故障类型进行仿真模拟,得到每种故障出现的三相电压、电流及零序电流波形,可明确看出故障出现后零序电流反相,进一步验证了判别零序电流相位法可应用于故障点的定位。根据该方法可行性,本文设计了电流采集及单片机数据处理存储系统。其中包括电流采集模块、信号处理模块、GPS模块、无线收发模块以及单片机的软件设计,本设计采用电流互感线圈实现三相电流信息的采集,采集后的信号通过信号处理模块进行整形滤波,其中包括滤波电路、放大电路及微处理器;其后借助单片机内部的10位模数转换器实现模拟信号转数字信号,并通过所设计的单片机程序将数据整合处理,其中借助GPS秒脉冲实现快速相位值计算的方式;最后采用无线传输来完成电流数据信息的远程传输工作,并在总站中对传输信息进行处理来判断故障点具体线路位置。本文对配电网故障定位系统进行测试,包括各模块的分开测试和零序电流采集终端的整体测试,给出具体测试结果,验证配电网故障定位系统工作的可靠性。在故障点前后两处进行实时采集得到三相限流IA、IB、IC以及零序电流I0,故障点前后共采集2组数据,对数据进行处理得到两点的零序电流相位图并将两者进行比较,故障点前后零序电流的幅值明显增大,并且两者相位差大致为180°。由此确定模拟配电线路的故障点在采集点A与采集点B之间,与本文理论依据相符合,进而验证此故障点定位系统的准确性。
[Abstract]:In order to ensure the industrial production and the normal life of the people, when the distribution network breaks out, the electric power workers should find out the cause of the fault in time, determine the location of the fault point, and fix the fault in the first time. In order to help the maintainers find the grounding fault point quickly, the method of phase method based on phase method is adopted to locate the single-phase grounding fault online. When the fault occurs, the phase of the zero-sequence current before and after the fault point will change from the same phase to the inverse phase, so the main idea of this design is to use the design to collect information at the online end. It includes three phase current acquisition and calculation of phase value of three phase current. When the value of current is superimposed as zero sequence current, the data is transmitted to the switchboard by wireless transmission mode, and the location of the specific fault point is judged at the switchboard. Phase method is often used in fault location. By comparing the advantages and disadvantages of many discriminant methods, this paper determines to use phase method, Simulink module in Matlab software to build transmission line, and simulate the possible fault types in the line. The waveforms of three-phase voltage, current and zero-sequence current of each fault are obtained, and the inverse phase of zero-sequence current after the fault appears can be clearly seen, which further verifies that the phase method of discriminating zero-sequence current can be applied to the location of fault point. According to the feasibility of this method, this paper designs the current acquisition and data processing storage system. It includes the software design of current acquisition module, signal processing module, GPS module, wireless transceiver module and single chip microcomputer. The design adopts current mutual inductance coil to collect three-phase current information. The collected signal is filtered by signal processing module, which includes filter circuit, amplifier circuit and microprocessor. Then the analog signal is converted to digital signal with the help of 10 bits A / D converter, and the data is integrated and processed by the single chip microcomputer program, in which the fast phase value calculation is realized by GPS second pulse. Finally, wireless transmission is used to complete the remote transmission of current data information, and the transmission information is processed in the terminal station to judge the location of the specific line at the fault point. In this paper, the fault location system of distribution network is tested, including the separate test of each module and the whole test of zero-sequence current acquisition terminal. The concrete test results are given to verify the reliability of the fault location system in distribution network. The three-phase current-limiting IA,IB,IC and zero-sequence current I _ 0 are collected in real time before and after the fault point, and two groups of data are collected before and after the fault point, and the zero-sequence current phase diagram of two points is obtained by processing the data and comparing them. The amplitude of zero-sequence current increases obviously before and after the fault point, and the phase difference between them is about 180 掳. Therefore, the fault point of analog distribution line is between the acquisition point A and the acquisition point B, which is in accordance with the theoretical basis of this paper, and then verifies the accuracy of the fault point location system.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM755

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