谐波和间谐波对全电能计量准确度的影响

Effect on Total Electric Energy Metering Accuracy of Harmonics and Inter-harmonics

对使用全电能计量方式的电子式电能表,在谐波、间谐波存在时,由矩形积分引起的积分误差进行了理论及仿真分析。分析表明:谐波下有功计量的准确度主要取决于采样率;间谐波下有功功率的准确度不仅与采样率有关,并且与纳入计算的周期数有关;存在一个特征周期数,使间谐波下的积分误差为0;稳定间谐波下有功电能的误差会随着时间的累加误差渐趋于0值。分析为谐波、间谐波条件下电能表的设计提供了一定的理论依据。

The error of rectangular integral algorithm under the condition of harmonics and inter-harmonics,employed in total electric energy meters is analyzed here.The analysis result shows that the active energy metering accuracy lies on the sampling rate under harmonics,and the accuracy under inter-harmonics lies on not only the sampling rate,but also the cycle number in metering.A characteristic cycle number which leads to no metering error exists.The metering error becomes smaller as the energy accumulating with time.The analysis provides reference for harmonics and inter-harmonics Watt-hour meters.