Author : Manar A . Khudhair, Alaa A. Al-Saffar and Rasheed S. Jasim

With increasing using of nonlinear electronic equipment at a wide range, total harmonics distortion (THD) in the line current has grown to be a considerable problem. The methods that include reducing harmonics in line current and power factor correction are required. Therefore, the essential target of this proposed work is to reduce the harmonics produced in the line current and improve the power quality of the load by the output voltage regulation and power factor correction (PFC). This paper presents a Single-Ended Primary Inductance Converter (SEPIC) at Discontinuous Conduction Mode (DCM) for automatic power factor Correction (APFC). The SEPIC converter is modeling by utilizing Current Injected Equivalent Circuit Approach (CIECA). The control system is applied by traditional linear control (TLC). The TLC has been modified by an optimization algorithm (OA) and adds an (inner or current). The proposed design of SEPIC-PFC is implemented by MATLAB and Simulink. According to the simulated dynamic behavior results, a unity power factor and 15% of total harmonics distortion (THD) reduction have been obtained comparing with previous work. Besides, a regulated DC output voltage has been achieved. The proposed control system has a low overshoot, small settling time, and steady-state error close to zero.

Keywords: Single-Ended Primary Inductance Converter (SEPIC); Discontinuous Conduction Mode (DCM); Automatic power factor Correction APFC; Current Injected Equivalent Circuit Approach (CIECA); Traditional Linear Control (TLC); Power Factor Correction (PFC); Total Harmonics Distortion (THD).