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This paper presents a highly efficient asymmetrical pulse-width modulated (APWM) full-bridge converter for renewable energy sources. The proposed converter adopts full-bridge topology and asymmetric control scheme to achieve the zero-voltage switching (ZVS) turn-on of the power switches of the primary side and to reduce the circulating current loss. Moreover, the resonant circuit composed of the leakage inductance of the transformer and the blocking capacitor provides the zero-current switching (ZCS) turn-off for the output diode without the help of any auxiliary circuits. Thus, the reverse recovery problem of the output diode is eliminated. In addition, voltage stresses of the power switches are clamped to the input voltage. Due to these characteristics, the proposed converter has the structure to minimize power losses. It is especially beneficial to the renewable energy conversion systems. To confirm the theoretical analysis and validity of the proposed converter, a 400 W prototype is implemented with the input voltage range from 40 to 80 V. [ABSTRACT FROM PUBLISHER]

In this paper, a discrete-time repetitive controller (RC) is proposed for a flyback inverter operating in continuous conduction mode (CCM), which has a simple structure, low cost, and high efficiency. Conventional controller results in poor control performance due to the effect of the right-half-plane zero in CCM operation. To achieve accurate tracking performance and disturbance rejection, the RC is developed and applied to the flyback inverter in CCM operation. In the RC scheme, a low-pass filter is used to allow tracking and rejection of periodic signals within a specified frequency range. A phase lead compensator is also used to compensate for the effect of the closed-loop system dynamics. The stability of the closed-loop system is derived, and the zero tracking error is achieved. Numerical simulations validated the proposed control approach, and experimental tests using a 200-W digitally controlled module-integrated converter prototype confirmed its feasibility. [ABSTRACT FROM PUBLISHER]