摘要
分析了采样法测量交流电有效值的测量误差,指出了同步采样难以严格实现的原因。以正弦交流电为例导出了测量误差与相对频偏及采样初始时刻的关系式,提出了一种可显著提高交流电有效值测量精度的改进方法。理论分析及对典型信号的数值计算均表明:传统算法的测量误差与相对频偏成正比,当频率漂移时测量误差明显增大;改进算法的测量误差与相对频偏无关,即使信号频率变化仍可保证有效值的测量精度。另外,改进算法还具有计算简单、实时性好等特点。
Error analysis of the conventional effective value measurement is carried out and the relation of measurement error with frequency deviation and initial time is derived, An improved algorithm is proposed for reducing the error of effective value measurement. Both theory and numerical computation show the error of conventional effective value measurement is proportional to frequency deviation, while the error of improved algorithm is independent of frequency deviation. The proposed algorithm is characterized by easy implementation and real -time responsibility, higher measuring precision still could be achieved even if no synchronous sampling technique is introduced.
出处
《现代电子技术》
2006年第2期134-135,138,共3页
Modern Electronics Technique
关键词
有效值测量
交流电
同步误差
相对频偏
effective value measurement
power AC
synchronous error
relative frequency deviation
