Fast Quasi Synchronous Harmonic Algorithm based on weight window function Mixed Radix FFT
According to the requirements of IEC61850 9 2LE, digital energy metering devices mainly adopt 80xfr fixed sampling rate. When the harmonic analysis is carried out under asynchronous sampling, it will produce large errors due to spectral leakage. Quasi Synchronous Algorithm has high accuracy, but the calculation process is complicated and the hardware overheads are high. Based on the characteristics of digital energy metering devices, this paper puts forward a Fast Quasi Synchronous Harmonic Algorithm using weight window function combined with Mixed Radix Fast Fourier Transform Algorithm. It will reduce the calculation by more than 94% Compared with the Triangle/Hanning/Nuttall4(III) Windowed Interpolated FFT Algorithm, the proposed algorithm will perform better in accuracy and has the feature that the more asynchronous of the sampling, the more obvious the error will be.
2016 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)