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Summary: A 2‐channel LED driver is presented herein, which possesses non‐pulsating input current and automatic current sharing. There are 4 features in the proposed LED driver. First, due to an input inductor, the input current is non‐pulsating, which makes the life of the renewable energy module or input capacitor longer. Second, each coupled inductor winding has a capacitor connected in series. Therefore, the dc magnetizing bias current is zero, and this can improve the iron core utilization, making the core loss and size reduced. Third, the number of LED channels can be extended by increasing windings. Fourth, the LED currents can be almost identical even if there are different LED numbers in LED strings. Eventually, the proposed LED driver is verified by simulation and experiment. [ABSTRACT FROM AUTHOR]

Summary: In this study, an extensible 2‐phase interleaved high step‐up converter with automatic current balance is presented. This converter uses coupled inductors and energy‐transferring capacitors to improve the voltage gain of the traditional 2‐phase interleaved boost converter as well as employs these energy transferring capacitors to do automatic current balance. Furthermore, the voltage gain can be enhanced not only by adjusting the turns ratio but also by increasing the numbers of phases, diodes, and energy‐transferring capacitors. Therefore, it can be used in high input current and high step‐up voltage applications. In this paper, the basic operating principles of the proposed converter are described and analyzed, and finally, its effectiveness is demonstrated by experiment. In addition, the field‐programmable gate array, named EP13T100C8N and manufactured by Altera Co, is used as a control kernel, and an experimental prototype, with input voltage of 12 V, output voltage of 200 V, and rated output power of 200 W, is given to provide the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

In this study, a new bridgeless buck power factor correction (PFC) rectifier is presented. The proposed buck PFC rectifier is designed to operate in the discontinuous conduction mode (DCM). Because of the DCM operation, the control scheme of the proposed buck PFC rectifier is simple and easy, and the reverse recovery problem of the diodes can be alleviated. Because the input current follows the input voltage naturally, the current loop circuit is not required. Thus, only the traditional voltage-mode control is employed to sense the output voltage, and a suitable control effort for the proposed buck PFC rectifier is generated to drive the power switches. Consequently, the output voltage of the proposed buck PFC rectifier can be kept at a desired value. Finally, the mathematical deductions and experimental results are provided to verify the effectiveness of the proposed bridgeless buck PFC rectifier. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel isolated high voltage-boosting converter, derived from the traditional forward converter, is presented in this paper. As compared with the traditional forward converter, the demagnetizing winding of the transformer in the proposed converter is used not only to demagnetize but also to improve the voltage conversion ratio. Therefore, the duty cycle is not limited, and the utilization of the transformer, also called coupled inductor, can be increased also. Furthermore, the proposed converter maintains the advantage of possessing a non-pulsating output current, leading to a small output voltage ripple. Moreover, by applying one additional voltage-boosting winding to the transformer, the voltage conversion ratio can be significantly improved. In addition, an active clamp circuit is employed in the proposed converter to reduce the voltage stress of the main switch, caused by the leakage inductance in the transformer, and the switches can achieve zero-voltage switching. Finally, the analysis of operating principles, choice of the turns, turns ratio, core size, and each wire size of the coupled inductor are described in detail, and the experimental results with a prototype with 12-V input voltage, 100-V output voltage, and 100-W output power are provided to verify the feasibility and effectiveness of the proposed converter. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel multi-output pulse-width-modulated control scheme based on time sharing is presented and applied to a two-output forward converter. Unlike the traditional two outputs, the main voltage output and the auxiliary voltage output can be controlled independently via two different switching periods and controllers, by inserting one auxiliary switch into the circuit. Put simply, the main turn-on time is used to control the main switch, the auxiliary turn-on time is used to control the auxiliary switch, and there are several auxiliary turn-on times within one main turn-on time. By this means, two stabilised output voltages are obtained with good cross-regulation. The prototype is verified by a 24 V input, the main voltage output, which has a rated output voltage of 56 V and a rated output power of 50 W, and the auxiliary output, which has a rated output voltage of 44 V and a rated output power of 40 W. [ABSTRACT FROM AUTHOR]