A Real-Time Lossless Compression Method for Harmonic Phasor Measurement Data Based on Golomb Coding

The harmonic distortion of commutation voltage is one of the important factors that increase the risk of commutation failure. Efficient acquisition and analysis of time-varying harmonic data are crucial prerequisites for analyzing the trends in maximum commutation overlap area and predicting commutation failure. This paper proposes a real-time compression method for harmonic phasor measurement data to improve the harmonic data processing efficiency. Firstly, the characteristics of harmonic data and the phasor angle transformation method are analyzed. Subsequently, a data classification method is introduced, along with a precision-based normalization technique to handle data from different frequency components. Following this, differential coding and Golomb coding are adopted to process measurement data originating from identical frequency components. Finally, the compressed coding values of all frequency components at that moment are assembled. The compression algorithm is tested using a historical dataset of harmonic measurements from a high voltage direct current transmission station. The results demonstrate the method's superior capability in effectively compressing frequency, amplitude, and phasor angle values of the harmonic measurement data.