Converters

About: Converters is a research topic. Over the lifetime, 22429 publications have been published within this topic receiving 387389 citations.

Core loss evaluation of high-frequency transformers in high-power DC-DC converters

Abstract: High-Frequency Transformers (HFTs) are one of the key elements of high-power converters in weight and volume restricted applications. HFTs are the main contributor to realize the voltage adaption, isolation requirements, as well as high-power density requirement of future high-power DC-DC converters. This paper addresses different methods to evaluate core losses of HFTs when they are exposed to power-electronic waveforms. Moreover, this paper addresses different magnetic materials which are suitable at high frequencies and presents the experimental results of magnetic core characterization under non-sinusoidal waveforms.

Minimum Distortion Point Tracking

Abstract: This article introduces the notion of minimum distortion point tracking (MDPT) : a control strategy where switching waveforms are optimally phase shifted to minimize aggregate ripple power for networks of dc–dc converters that are connected in series or parallel at the input or output. In a sense, MDPT generalizes the ubiquitous concept of interleaving in balanced systems to a broad class of asymmetric series- or parallel-connected dc–dc converters. For networks of up to one hundred interconnected power converters, MDPT demonstrates a one to two order of magnitude reduction (−14 to −22 dB) in distortion power. We present and experimentally verify three algorithms that can dynamically solve the MDPT optimization problem on a network of three input-parallel connected dc–dc buck converters handling 1.8 kW. The experimental results illustrate an up to $\text{3.06}\times$ reduction in the peak-to-peak ripple of the parallel-side bus voltage and convergence close to an optimal steady-state solution in 5 ms.

Analysis, design and implementation of an isolated full-bridge converter for battery charging

Abstract: This paper purposes the development of an isolated battery charger. In energy storage systems, these devices are essential, performing batteries charging in the way to maintain their lifecycle and safety since they are main responsible for the costs associated with these systems. In many works theses circuits are implemented through bidirectional Full-Bridge converters. These converters require auxiliary circuits to reduce their switching losses. However, circuits such as snubbers or voltage clampers are not adequately addressed in these works since their use is undesirable for bidirectional operation. To eliminate these circuits in isolated converters, this work presents a switching technique applied in a Full-Bridge converter with the objective to reduce overvoltage in semiconductors and make it suitable for use in bidirectional converters, as in the charge of battery banks.

Passive Component Modeling and Optimal Size Allocation for Hybrid-Resonant Switched Capacitor DC-DC Converters

Abstract: This paper explores methods to optimize hybrid-resonant switched capacitor (ReSC) DC-DC converters. A technique is presented that leads to optimal size allocation between flying capacitors and inductor with a constraint on total size of passives. Both the losses in the active semiconductor devices and in the magnetic component are modeled. For coreless inductors, the low-frequency DC losses and the high-frequency AC (skin effect) losses are treated separately. For cored inductors, the Improved Generalized Steinmetz Equation (iGSE) is used to model the core losses, and a design algorithm and example are presented. It is shown that for optimal operation, flying capacitors and inductor should be allocated roughly similar size.