Effects of Windowing on the Measurement of Harmonics and Interharmonics in the IEC Standard Framework

This paper studies the effects of the most commonly used window functions, rectangular and Hanning windows, on the processing of harmonics and interharmonics in power system in the framework of the standards defined by the International Electrotechnical Commission. The effect of the two window functions on the processing of fluctuating harmonics and interharmonics is studied. The effect of spectral leakage due to synchronization errors with the window width in the determination of the harmonic and interharmonic groups and subgroups using both windows, is also considered in the paper. From the results obtained it can be concluded that in the new IEC standard framework, the rectangular window is the most appropriate window function for a harmonic and interharmonic measurement instrumentation any measurement conditions