In this paper, we propose a new method for phase shifting based on the notch filtering and phase locked-loop. The notch filter and phase locked-loop estimate input frequency and produce two orthogonal sinusoidal signals which proposed phase shifter use them to shift input signal. Then, based on this phase shifter an adaptive algorithm for measuring the phase margin of a plant is proposed. The simulation results depict very good efficiency of the proposed algorithm.
展开▼