Orthogonal Signal Generation based PLL using Arbitrary Order Exact Differentiator with Inherent Disturbance Rejection for Single Phase Systems

Abstract

Use of Derivative based PLL is one of the simplest and fastest solution for phase-locked loops in single phase systems. The dynamics of Derivative-PLL are comparatively better than other methods, but it exhibits high frequency noise amplification and also under performs in non-ideal grid conditions. In this paper, a robust arbitrary order exact differentiator is proposed as a solution to generate noise free, fast and exact orthogonal signal by utilizing second order generalized differentiator method which is used further to formulate a PLL that is immune to high frequency noise and performs well under various disturbances in voltage, frequency, phase, harmonics, noise and DC-offset in grid voltage. The proposed PLL is modeled using MATLAB/SIMULINK and is tested for standard grid conditions. Typical results are reported and are compared with existing PLLs. It is found that the proposed method is not only simple and immune to noise and disturbances but also superior compared to other PLLs.