摘要
为了解决传统的剩余电流保护中有效值测量不准确的问题,提出了一种基于快速傅里叶变换的剩余电流真有效值算法。从理论上说明了平均值测量法测量的有效值与真有效值的区别,分析了平均值测量方法的缺点,同时对快速傅里叶变换如何计算真有效值进行了理论推导,最后利用Matlab/Simulink对提出的方法进行了仿真。结果表明,算法计算的有效值精度更高,可以避免剩余电流波形畸变的影响。
The average measure method is often adopted to measure the true Root Mean Square （RMS） of the residual current in the traditional residual current protection technique. Residual pulsating DC component appears in power grid due to the use of power electronic equipment, so the method is no longer accurate. An approach based on fast Fourier transform （FFF） was proposed to calculate the true RMS of residual current. Firstly, the paper explains the difference between the RMS measured by the average measure method and the true RMS in theory and analyzes the shortcomings of this measurement method. Secondly, theoretical derivation of calculating the true RMS by FFT is presented. Finally, the approach based on FFT is simulated in Matlab/Simulink. The results show that the RMS calculated by the approach based on FFT is more accurate and the approach can avoid the impact of residual current waveform distortion.
出处
《电器与能效管理技术》
2015年第17期13-16,65,共5页
Electrical & Energy Management Technology
基金
上海市自然科学基金项目(12zr1411700)
上海市闵行区科技项目(2014MH134)
