High Frequency Power Inverter Research Articles

Design a High Frequency Power Inverter Using Ferrite-Core Transformer for Ohmic Heating of Liquid Conducting System

Design a High Frequency Power Inverter Using Ferrite-Core Transformer for Ohmic Heating of Liquid Conducting System

Vehicular Integration of Wireless Power Transfer Systems and Hardware Interoperability Case Studies

Several wireless charging methods are under development or available as an aftermarket option in the light-duty automotive market. However, there are not a sufficient number of studies detailing the vehicle integration methods, particularly a complete vehicle integration with higher power levels. This paper presents the design, development, implementation, and vehicle integration of wireless power transfer (WPT) based electric vehicle charging systems for various test vehicles. Before having the standards effective, it is expected that WPT technology first will be integrated as an aftermarket retrofitting approach. Inclusion of this technology on production vehicles is contingent upon the release of the international standards. The power stages of the system are introduced with the design specifications and control systems, including the active front-end rectifier with power factor correction, high frequency power inverter, high frequency isolation transformer, coupling coils, vehicle side full-bridge rectifier and filter, and the vehicle battery. The operating principles of the control and communication systems are presented. Aftermarket conversion approaches, including the WPT on-board charger integration, WPT CHAdeMO integration, and WPT direct battery connection scenarios, are described. The experiments are carried out using the integrated vehicles and the results obtained to demonstrate the system performance including the stage-by-stage efficiencies.

Experimental Validation of Comprehensive Steady-State Analytical Model of Bidirectional WPT System in EVs Applications

A flexible, automatic, reliable, and safe charging and discharging system for electric vehicles (EVs) and hybrid EVs is crucial in vehicle-to-grid (V2G) operation. The bidirectional inductive wireless power transfer system (BIWPTS) is an ideal solution in this situation. With authentic power-flow models for the BIWPTS in hand, designers and operators can predict, optimize, and analyze the interaction performance between the EV and the grid. Thus, this paper presents a harmonics-based theoretical power-flow model for BIWPTS for charging and discharging EVs in V2G applications. The proposed model provides accurate estimation for the active and reactive power flow during V2G and grid-to-vehicle modes. Moreover, the impact of the circuit losses and harmonics, due to the high-frequency power inverters, on the power-flow performance is investigated. This effect is stated mathematically by four novel power-flow criteria formulas. New conditions for achieving maximum active and reactive power, and unity and zero power-factor system operation, are also developed. The sensitivity of the circuit performance to the variation of its parameters has been studied. For validation purposes, a computer-based model and experimental platform of BIWPTS for EV applications are developed and tested. The comparison between the theoretical, simulation, and experimental results verified the proposed models and analysis.

The infeasibility of self-regulating constant-current-fed class E power inverters

Because of their high operating efficiency, class E circuits have been shown to be useful in high-frequency power inverters and converters. Typical circuits are constant-fed, i.e. they require an RF choke in the DC-feed line, and must obtain load regulation by means of appropriate feedback control. A class E inverter with finite DC-feed inductance that provides perfect load regulation without feedback control has been suggested. However, such class E circuits generally have higher sensitivities to component variations (except load resistance) than do their constant-current-fed counterparts. Thus, the possibility of load-independent operation of constant-current-fed class E inverters is of interest. The authors show that there is no way to configure constant-current-fed E inverter so that it will exhibit load-independent properties except for a trivial circuit with zero output voltage.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

New efficient high-frequency power inverter with inductive energy processing loops

This paper presents state-of-the art developments in the sequential-switching high-power high-frequency inverter using reverse-blocking thyristors (SCRs) or GTOs. The newly developed sequential inverters can economically produce a large amount of power in the ultrasonic frequency range between 10 kHz and about 100 kHz. The control implementation of the inverter is demonstrated on the basis of induction heating and melting applications in industry. The circuit analysis is described and the performance evaluations associated with the voltage regulation characteristics and control frequency control characteristics are illustrated generally in terms of normalized variables and parameters.

Derating of semiconductor fuselinks for use in high-frequency applications

High-breaking-capacity fuselinks used in high-frequency power inverter (50 kHz) circuits sometimes operate spuriously below rated current. Premature melting is more common when the fuselinks are mounted near associated cables or semiconductors. This unexpected operation can be attributed to skin and proximity effects, which are consequences of the electromagnetic induction between parallel current-carrying conductors. To prevent undue action of the fuselinks, their ratings must be reduced in accordance with a function of frequency, fuse dimensions and the distance between the fuselink and current-carrying conductors.