A phasor extraction algorithm based on a modified least square error method which can be used for a high speed digital distance relay is proposed. To obtain stable phasor values very quickly, first, a lowpass filter which has very short transient peri...
A phasor extraction algorithm based on a modified least square error method which can be used for a high speed digital distance relay is proposed. To obtain stable phasor values very quickly, first, a lowpass filter which has very short transient period and no overshoot is used. Secondly, the conventional least square error method is modified to the one having the data window of 3 samples by applying a FIR filter which removes the DC-offset component in current relaying signals.