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This paper presents a new isolated single-stage pulse-width modulation rectifier system based on the recently presented Swiss rectifier topology providing the isolation by replacing a buck with a forward converter. The principle of operation and a new modulation technique which compensates the reactive power generated by the input filter at light load and maximizes the power factor are discussed. Furthermore, the analytical equations for the stress in the semiconductor devices useful for the system optimization are derived. The proposed topology and modulation technique are experimentally validated on a 3.3-kW 115 Vac to 270 Vdc prototype demonstrator. [ABSTRACT FROM AUTHOR]

In this article, analysis and design of a 3.3-kW isolated single-stage three-phase buck-type rectifier for aircraft applications is presented. The operating principle and modulation method of the proposed rectifier are introduced. The advantageous zero-voltage switching (ZVS) feature in all of the switching transitions is analyzed. A comparison with the VIENNA Rectifier III is done, being different both in the phase-leg implementation and the modulation sequence. A detailed rectifier design guideline is discussed and losses estimations are provided aiming at reaching 93.7% overall efficiency, including the EMI (electromagnetic interference) filter. Simulation waveforms are presented. Finally, experimental results obtained with the designed 3.3-kW hardware demonstrator are provided. The results verify achievement of ZVS in all of the switching transitions from full load down to 50% of nominal load, while exhibiting 1.9% THD $_I$ (total harmonic distortion) and 0.9996 PF (power factor) at nominal power, ultimately showing very good agreement to the simulation results. This article is accompanied by a video demonstrating experimental operation of the proposed rectifier at nominal input voltage, output voltage, and output power. [ABSTRACT FROM AUTHOR]

Several boost-derived topologies are analyzed and compared for an aerospace application that uses a 100 V voltage bus. All these topologies have been designed and optimized considering the electrical requirements and the reduced number of space-qualified components. The comparison evaluates the power losses, mass, and dynamic response. Special attention has been paid to those topologies that may cancel the inherent right half plane zero (RHP) zero of the boost topology. Experimental results of the less common topologies are presented. [ABSTRACT FROM AUTHOR]

This article analyses the fundamental aspects of the principal resonant network topologies for inductive power transfer systems. From the analytical derivation, different features, such as the variation of the coupling factor or load changes, are studied. Based on this study, a resonant series–series topology is selected, which cancels the leakage inductance. Due to the specifications, the air gap distance and its tolerance ($\pm \text{12}\%$) produce a wide variation of the coupling factor of the inductive link. Therefore, through fast three-dimensional simulations by finite elements, the inductive link is designed so that this variation is minimized. This maintains the resonance and the designed system, in turn, behaves like a voltage source regardless of power, and thus, evades the implementation of a control stage. A dc–dc converter is constructed where the distance between the primary and secondary side vary from 35 to 45 mm, and the power ranges from 0 to 5 kW. The output voltage range goes from 38 to 55 $V_{\text{DC}}$. Experimental results for the dc–dc converter report an efficiency of over 94%. [ABSTRACT FROM AUTHOR]

This paper presents a primary-parallel secondary-series multicore forward microinverter for photovoltaic ac-module application. The presented microinverter operates with a constant off-time boundary mode control, providing MPPT capability and unity power factor. The proposed multitransformer solution allows using low-profile unitary turns ratio transformers. Therefore, the transformers are better coupled and the overall performance of the microinverter is improved. Due to the multiphase solution, the number of devices increases but the current stress and losses per device are reduced contributing to an easier thermal management. Furthermore, the decoupling capacitor is split among the phases, contributing to a low-profile solution without electrolytic capacitors suitable to be mounted in the frame of a PV module. The proposed solution is compared to the classical parallel-interleaved approach, showing better efficiency in a wide power range and improving the weighted efficiency. [ABSTRACT FROM AUTHOR]

In this paper, a multiphase converter where the phases are coupled by transformers is proposed to implement a minimum energy-storage converter. Advantages and drawbacks of this topology are analyzed and validated by means of three prototypes. The two main advantages of the minimum energy-storage concept are that the converter can be operated at very low frequency since the transient response is not affected by the switching frequency, thus achieving very high efficiency while at the same time, providing a fast energy transfer between the input and the output. Since this topology operates (ideally) with no energy storage, energy flow into the magnetic elements of the topology needs to be adequately controlled. The main application of this topology is a “dc–dc transformer” for two-stage power architectures. [ABSTRACT FROM AUTHOR]