Modeling and Control of Bridgeless Single-Switch Non-Inverting AC-DC Cuk Converter in DCM

Abstract

In this paper, an averaged nonlinear model of a bridgeless single-switch non-inverting ac-dc Cuk converter in DCM is derived. In addition, a current-mode control scheme is designed to operate the power converter in buck and boost modes during line and load variations. In contrast, the previous research endeavors of the bridgeless Cuk converter presented a single operation mode, and accommodation of large disturbances has not been discussed. The proposed control method is compared with the classical PI controller to investigate their performance. MATLAB simulation results show that the proposed control scheme improves the dynamical response, tracks the reference voltage, and provides wide operating range.

Simplified Nonlinear Current-Mode Control of DC-DC Cuk Converter for Low-Cost Industrial Applications

“…In other words, the current-mode control method yields fast response and enhanced transient characteristics. On the contrary, the voltage-mode control of systems with a right-half plane zero results in a slow system response and a narrow bandwidth [ 25 ]. Hence, the simplified nonlinear current-mode controller enjoys simplicity in control circuit structure, robustness against large disturbances, and suitability for a non-minimum phase power converter.…”

Robust current-mode control of bridgeless single-switch SEPIC PFC converter

“…The outer voltage loop contains the sensed output voltage, which is compared with a reference voltage V r to generate a voltage error signal. The voltage error signal passes through a proportionalintegral (PI) compensator to generate a reference inductor current IR [8], which is defined as (6).…”

“…The control method can be achieved using the inductor current iL1. The rectified value of the current iL1 passes through the gain K [8]. The inner current loop is compared with the reference current IR in (6) to generate the current-mode control law.…”

“…The AC-DC bridgeless Cuk and SEPIC PFC converters have also been introduced to operate in buck and boost modes. Proportional-integral (PI) control [7] and current-mode control [8] schemes have been presented for bridgeless Cuk converters. The SEPIC PFC converters in [9]− [16] are designed to work in discontinuous conduction mode (DCM) to gain some advantages, such as zero-current turn-on in switches and zero-current turn-off in output diode.…”