LAUSR

Abstract Harmonic time-frequency characteristics are the most important foundation for harmonic power flow calculation, harmonic energy meter, and harmonic treatment. However, the existing time-frequency analysis methods have the drawback as either single measuring data or low measuring precision. To address these issues, a digital prolate spheroidal window-based S-transform (DPSWST) is proposed in this paper for a more accurate analysis of the time-varying harmonics in power systems. The DPSWST, which uses the prolate spheroidal window as its kernel function, has many excellent performances such as superior time-frequency distribution, simple parameter selection, and easy implementation. Due to these characteristics, the DSPWST can effectively analyze and describe the essential characteristics of the time-varying harmonics in the power system. The effectiveness and reliability of the proposed algorithm are supported through the validation of simulation and practical experiments.