A phasor measurement algorithm based on mathematical morphology and instantaneous reactive power theory

This paper presents a new algorithm which employs morphological filter and instantaneous reactive power theory for phasor measurement. A preprocessor is proposed to removes the decaying DC component from the input signal with a delay of two samples. The effects of sampling rate, time constant, frequency shift, harmonics and fault inception angle on the performance of the proposed algorithm have been studied. Comparison studies have been also carried out between the proposed algorithm and the two popular phasor estimation algorithms, the full cycle Discrete Fourier Transform (FCDFT) and the full cycle least error squares (LES) algorithm, using data generated by software PSCAD/EMTDC. The simulation results show that the proposed algorithm is of high accuracy, fast convergence and good robustness.