摘要
针对常用的硬件测频法和软件测频法分别存在硬件设计复杂、软件测量误差较大的问题,提出了一种基于线性插值的电网频率测量方法。该方法首先找出半波内与第一个过零点最近的2个采样点,利用线性插值算出该过零点与后一个采样点之间的时间T1;其次找出半波内与下一个过零点最近的2个采样点,利用线性插值算出该过零点与前一个采样点之间的时间T3;再次计算半波内第一个和最后一个采样点之间的时间T2;最后将T1、T2、T3相加,即可算出电网频率f。测试结果表明,该方法测量误差为±0.05Hz,且计算过程简单。
In view of problems of complex design in hardware and big measuring error in software respectively existed in frequency measuring methods with hardware and software, the paper proposed a power frequency measuring method based on linear interpolation. Firstly, the method finds two nearest sampling points to the first zero-crossing point in half-wave and uses linear interpolation to calculate T1 between the zero-crossing point and the later sampling point. Then it finds two nearest sampling points to the next zero-crossing point in half-wave and uses linear interpolation to calculate Ta between the zero- crossing point and the former sampling point. And then it calculates Tz between the first sampling point and the latest one. At last, it calculates power frequency f by adding T1, T2 and Ta. The test result showed that measuring error of the method is±0.05 Hz with simple calculation process.
出处
《工矿自动化》
北大核心
2012年第6期99-102,共4页
Journal Of Mine Automation
关键词
电力系统
电网频率测量
软件测频
硬件测频
线性插值
power system, power frequency measurement, frequency measurement with software,frequency measurement with hardware, linear interpolation
