Supraharmonic analysis using subsampling

Researchers and standard-setting organizations recently have paid much attention to power quality disturbances in the frequency range between 2–150 kHz, which is also referred to as supraharmonics. The majority of the commercial PQ monitors cannot access this high frequency without hardware and firmware update for more complex processor and Analog to Digital Converter. The central focus of this work is to present a technique to access the supraharmonics without significantly modification of the hardware and software of the PQ analyzers. The technique is based on analog filter banks and subsampling approach. The use of subsampling technique allows the reduction of the number of samples processed by the Fast Fourier Transform FFT. Through a systematic analysis, it was verified that the proposed methodology reduces computational complexity.