【毕业设计】介质损耗角检测系统的研究与设计.doc

介质损耗角检测系统的研究与设计 摘要 电力系统中检测高压设备的运行可靠性和发现电气绝缘方面缺陷，介质损耗角的测量必不可少。介质损耗角是一项反映高压电气设备绝缘性能的重要指标。本文介绍了介质损耗角的基本概念和其意义，简单分析了介质损耗角检测的传统方法，详细介绍了测量介损角的数字测量方法——基波相位分离法。提出了一种非同步采样条件下采用基波相位分离法的补偿算法，即采用等时间间隔电压、电流信号进行采样，同时对信号周期波动产生的误差进行补偿。基于该算法合理配置测量系统的硬件实现方案。采用美国国家仪器公司（NI）研制开发的实验室虚拟仪器工程平台LabVIEW，对其进行仿真和试验。仿真和试验结果表明该算法在增加较少运算量的同时提高了介质损耗角的测量精度。开发出的测量系统很好的实现了电容型设备介质损耗角的在线检测，它突破了传统检测方法在数据处理、显示等方面的限制，并具备很高的智能度和性价比。 关键词：介质损耗角；虚拟仪器；labVIEW；非同步采样算法 Research and design of measurement system of dielectric loss angle Abstract It is indispensable to measure the dielectric loss angle in the process of measuring the working security of electric equipment and discovering the defect of electrical insulation in the system of electric power. The dielectric loss plays an important role to reflect the insulated property of high voltage electric equipment. The concept and significance of dielectric loss angle is introduced in this paper. The traditional methods and a digital method called fundamental harmonic phase separation of measurement of dielectric loss angle is analyzed. An algorithm for fundamental harmonic phase separation under asynchronous sampling is gave that the voltage and current signals were sampled by equal time intervals and errors caused by the signal period fluctuation were compensated. The hardware implementation for a measuring system based on the algorithm was described in this paper. The scheme is simulated and tested by LabVIEW(Laboratory Virtual Instrument Engineering Workbench), which is invented by NI co. The results of simulation and tests show that measuring system invented implement measurement of electric capacity equipment on line. It breaks the limit of handling and showing data in the traditional measurement, which has higher intelligent ability and ratio between property and price. Key words: dielectric loss angle; virtual instruments; LabVIEW ; asynchronous sampling 目 录 摘 要…………………………………………….……………………………….………Ⅰ Abstract…………………………………………………………………………..….Ⅱ 1 绪论………………………………