A new digital phase estimation technique based on centroid formula

Synchronization is a crucial aspect of grid-connected converters. Grid voltage amplitude, frequency, and phase are the most important parameters that have to be estimated in order to inject current with unity power factor. Compared to three-phase power systems, the estimation of these parameters for single-phase grids is more challenging since less information is available. This paper presents a novel approach to estimate the phase angle of a sine wave signal. This approach, based on computing the x-coordinate centroid formula, does not require a synchronous reference frame, a quadratic signal generator, or an amplitude estimation of the input signal. An application of this method for single-phase power systems is proposed. Experimental comparisons with other popular techniques under different test scenarios such as phase jump, frequency jump, harmonic distortions, and DC offset show that the proposed method gives satisfactory performances in terms of dynamic response and robustness.