Resonance-based wireless power delivery is an efficient technique to transfer power over a relatively long distance. This technique typically uses four coils as opposed to two coils used in conventional inductive links. In the four-coil system, the adverse effects of a low coupling coefficient between primary and secondary coils are compensated by using high-quality (Q) factor coils, and the efficiency of the system is improved. Unlike its two-coil counterpart, the efficiency profile of the power transfer is not a monotonically decreasing function of the operating distance and is less sensitive to changes in the distance between the primary and secondary coils. A four-coil energy transfer system can be optimized to provide maximum efficiency at a given operating distance. We have analyzed the four-coil energy transfer systems and outlined the effect of design parameters on power-transfer efficiency. Design steps to obtain the efficient power-transfer system are presented and a design example is provided. A proof-of-concept prototype system is implemented and confirms the validity of the proposed analysis and design techniques. In the prototype system, for a power-link frequency of 700 kHz and a coil distance range of 10 to 20 mm, using a 22-mm diameter implantable coil resonance-based system shows a power-transfer efficiency of more than 80% with an enhanced operating range compared to ~40% efficiency achieved by a conventional two-coil system.

Design and Optimization of Resonance-Based Efficient Wireless Power Delivery Systems for Biomedical Implants

An isolated three-port bidirectional dc-dc converter composed of three full-bridge cells and a high-frequency transformer is proposed in this paper. Besides the phase shift control managing the power flow between the ports, utilization of the duty cycle control for optimizing the system behavior is discussed and the control laws ensuring the minimum overall system losses are studied. Furthermore, the dynamic analysis and associated control design are presented. A control-oriented converter model is developed and the Bode plots of the control-output transfer functions are given. A control strategy with the decoupled power flow management is implemented to obtain fast dynamic response. Finally, a 1.5 kW prototype has been built to verify all theoretical considerations. The proposed topology and control is particularly relevant to multiple voltage electrical systems in hybrid electric vehicles and renewable energy generation systems.

An Isolated Three-Port Bidirectional DC-DC Converter With Decoupled Power Flow Management

Induction heating (IH) technology is nowadays the heating technology of choice in many industrial, domestic, and medical applications due to its advantages regarding efficiency, fast heating, safety, cleanness, and accurate control. Advances in key technologies, i.e., power electronics, control techniques, and magnetic component design, have allowed the development of highly reliable and cost-effective systems, making this technology readily available and ubiquitous. This paper reviews IH technology summarizing the main milestones in its development and analyzing the current state of art of IH systems in industrial, domestic, and medical applications, paying special attention to the key enabling technologies involved. Finally, an overview of future research trends and challenges is given, highlighting the promising future of IH technology.

/pdf/induction-heating-technology-and-its-applications-past-218lub4zxh.pdf

Induction Heating Technology and Its Applications: Past Developments, Current Technology, and Future Challenges

The number and diameter of strands to minimize loss in a litz-wire transformer winding is determined. With fine stranding, the AC resistance factor can be decreased, but DC resistance increases as a result of the space occupied by insulation. A power law to model insulation thickness is combined with standard analysis of proximity-effect losses to find the optimal stranding. Suboptimal choices under other constraints are also determined.

/pdf/optimal-choice-for-number-of-strands-in-a-litz-wire-4jp058ex2a.pdf

Optimal choice for number of strands in a litz-wire transformer winding

A higher order passive power filter (LLCL filter) for the grid-tied inverter is becoming attractive for industrial applications due to the possibility to reduce the cost of the copper and the magnetic material. However, similar to the conventional LCL filter, the grid-tied inverter is facing control challenges. An active or a passive damping measure can be adopted to suppress the possible resonances between the grid and the inverter. For an application with a stiff grid, a passive damping method is often preferred for its simpleness and low cost. This paper introduces a new passive damping scheme with low power loss for the LLCL filter. Also, a simple engineering design criterion is proposed to find the optimized damping resistor value, which is both effective for the LCL filter and the LLCL filter. The control analysis and the power loss comparison for different filter cases are given. All these are verified through the experiments on a 2-kW single-phase grid-tied inverter prototype using proportional resonant controllers. It is concluded that, compared with the LCL filter, the proposed passive damped LLCL filter can not only save the total filter inductance and reduce the volume of the filter but also reduce the damping power losses for a stiff grid application.

A New Design Method for the Passive Damped LCL and LLCL Filter-Based Single-Phase Grid-Tied Inverter

The parasitic effects in stranded, twisted, and Litz wire windings operating at high frequencies are studied. The skin and proximity effects that cause the winding parasitic resistance of an inductor to increase with the operating frequency are considered. An expression for the AC resistance as a function of the operating frequency is given. The measured and calculated values of the inductor AC resistance and quality factor are plotted versus frequency and compared. The theoretical results were in good agreement with those experimentally measured.

/pdf/modeling-litz-wire-winding-losses-in-high-frequency-power-1j4djydmjz.pdf

Modeling Litz-wire winding losses in high-frequency power inductors

A high-frequency model of iron-powder-core inductors is studied. The skin and proximity effects that cause the winding parasitic resistance to increase with the operating frequency are considered. The inductor self-resonance due to the parasitic capacitances is taken into account as well. The frequency response of the inductor model is compared to that of an experimentally tested iron-powder-core inductor. Expressions giving the ac resistance as a function of the operating frequency are given. These expressions allow for an accurate prediction of the inductor power loss over a wide frequency range. The measured and calculated values of the inductor impedance magnitude and phase, the real and imaginary parts of the inductor impedance, the inductance, and the inductor quality factor are plotted versus frequency and compared. Theoretical results were in good agreement with those experimentally measured. A design procedure for solid wire winding inductors based on the results of the inductor modelling is also given in the paper.

Modelling winding losses in high-frequency power inductors

A model of ferrite core inductors is presented. The skin and proximity effects which increase the ac resistance of the inductor winding are considered. The core losses are studied. Power losses of the inductor are modeled by means of a frequency dependent series resistance. Parasitic capacitances which affect the inductor high-frequency operation are also considered. The model is applicable to cores with and without an air gap. Calculated and measured inductor parameters such as equivalent series inductance (ESL), reactance, equivalent series resistance (ESR), impedance magnitude and phase, and quality factor are plotted as functions of the operating frequency and compared. Calculated results were in good agreement with the measured ones up to the inductor self-resonant frequency. As a consequence, the discussed model is suitable to represent the frequency response of ferrite core inductors and can be effectively used for designing inductors. >

/pdf/high-frequency-models-of-ferrite-core-inductors-4spl31ehop.pdf

High-frequency models of ferrite core inductors

A design procedure which allows for assembling power inductors with minimum overall power loss is given in this paper. The inductor design is carried out by using an iterative procedure where the operating flux density is increased from zero to the saturation value. For any given value of the flux density the winding resulting in the lower AC resistance is determined. Both solid round wire and Litz wire windings are considered. The significance of the paper is that the design procedure allows for the combination of the flux density and winding which result in the lower power loss operation is determined. Therefore, inductors designed by following this procedure result in a high efficiency and minimum temperature rise.

Minimum copper and core losses power inductor design

A practical procedure for measuring the control-to-output transfer function of a PWM buck converter operated in continuous current mode (CCM) is given. It is shown that a simple, low cost measurement setting can be used. The results of the presented procedure shows that the frequency behavior of a PWM buck converter depends on the filter capacitor equivalent series resistance (ESR). It is also shown that models of a PWM buck converter presented in previous works yields an accurate result only if the capacitor ESR variation with the operating frequency is taken into account. The result of this work can be used in designing an appropriate feedback loop of the converters.

/pdf/open-loop-small-signal-control-to-output-transfer-function-3r8e1aj10q.pdf

Open loop small-signal control-to-output transfer function of PWM buck converter for CCM: modeling and measurements

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

M. Bartoli

Author Tools

Chat about Author