A new joint sliding-window ESPRIT and DFT scheme for waveform distortion assessment in power systems

This paper proposes a novel scheme that jointly employs a sliding-window ESPRIT and DFT for estimating harmonic and interharmonic components in power system disturbance data. In the proposed scheme, separate stages are utilized to estimate the voltage fundamental component, harmonics and interharmonics. This includes the estimation of the fundamental component from lowpass filtered data using a sliding-window ESPRIT, of harmonics from a sliding-window DFT with a synchronized window, and of interharmonics from the residuals by applying the sliding-window ESPRIT. Main advantages of the approach include high resolution and accuracy in parameter estimation and significantly reduced computational cost. Experiments and comparisons are made on both synthetic and measurement data. Results have shown the effectiveness and efficiency of the proposed scheme.

► We propose a novel SW ESPRIT-DFT scheme to estimate waveform distortion in power systems. ► Separate stages are used to estimate the fundamental, harmonics and interharmonics. ► Advantages of proposed scheme include high accuracy and reduced computational cost. ► Time-varying harmonics/interharmonics are estimated with high frequency resolution. ► Analysis on synthetic and measurement data shown the efficacy of the proposed scheme.