电子式互感器误差校验装置的研究

Research for Electronic Instrument Transforms Error Calibration Device

描述了电子式互感器(简称EIT)的优点和重要作用,依据IEC60044-7和IEC60044-8标准,给出了数字量输出EIT的误差定义:比差、相位差和相位误差。介绍了数字量输出型EIT误差校验装置的设计原理:采用FPGA设计单独的硬件采样环节,利用绝对测差、频率可变的全面数字锁相环的设计方案、按照标准的通信协议解码合并单元的数字量输出信号;PC机采用win2000操作系统,软件用微软的C#语言接收微处理器初步处理的数据、采用准同步等算法处理信号,研制出针对数字量输出的便携式电子式互感器误差校验装置,硬件电路简单,测量简单方便,数据准确可靠。

The excellences and important functions of electronic instrument are described firstly. The definition of amplitude error, phase error and composite error for digital output of EIT are given in the paper based on the standard of IEC60044-7 and IEC60044-8. Subsequently the design principle of error calibration device is introduced： it adopts the individual sampling circuit of Field Programmable Gate Array （FPGA）, by the use of the project of the absolute error and all digital phase-locked loop according to the digital quantity of the standard corresponding to output signals. Software adopts C# to program and deal with the signals ground on non-synchronized sampling. The hardware is simple, the measurement is convenient and the datum is precise.