TLBO-Optimized FOPI Controller for Three-Phase Active Rectifier Using ZDPC Technique

Abstract

Traditional direct power control (DPC) method is a simple and proficient way to control the three-phase active rectifiers, but its response is unacceptable when the power converter is subjected to abnormal grid conditions. This paper proposes the zero direct power control (ZDPC) methodology with teaching–learning-based optimal fractional order proportional integral (FOPI) controller to improve the performance of DPC method under unbalanced and harmonically polluted grid voltage conditions. In the proposed approach, a better performance is obtained by directly controlling the instantaneous active and reactive powers of the harmonic component of currents considering a predefined lookup table. In the proposed technique to achieve the complete elimination of the impact of the grid disturbance, the reference of both active and reactive powers is explicitly provided from outside of the controller and is set to zero. The teaching–learning-based optimized (TLBO) FOPI controller is utilized for better regulation of dc bus voltage. Additionally, the proposed approach does not require any prior familiarity with disturbance behavior, sequence components of voltages and currents. Also, it does not need harmonic component extractions. In the proposed control technique, a simple phase-locked loop (PLL) is utilized to extract the fundamental component of currents and to obtain the angular position of the grid voltage space vector in the stationary $$\upalpha $$ - $$\upbeta $$ reference frame. The simulation results have confirmed the supremacy of the proposed ZDPC with optimal FOPI under unbalanced and harmonically contaminated grid conditions as compared to conventional DPC.