Half-bridge Inverter Research Articles

Computational Modeling of Two Partly Coupled Coils Supplied by a Double Half-Bridge Resonant Inverter for Induction Heating Appliances

In this paper, an induction heating system composed of two partly coupled coils connected to a double half-bridge resonant inverter is deeply analyzed. Induction coils are electrically characterized by their electrical equivalents, usually a series RL circuit, where the inductance is determined by the magnetic energy stored in the system and the resistance is associated with the power dissipated in the load, generally, a metallic workpiece. The aim of this work is to obtain the electrical equivalent of an inductor system with two concentric coils used in domestic cookers by means of computational methods, in order to be included into the models used in computational aided electronic tools to simulate the time-domain behavior of the associated electronics. The multiple-coil system is characterized with a frequency-dependent impedance matrix, where the diagonal terms are the impedance of each isolated coil, and the nondiagonal terms are coupling impedance components describing the mutual coupling between coils. The impedance matrix is calculated with finite-element analysis tools, and equivalent passive networks are proposed to perform time-domain simulation with a good accuracy in the frequency range of interest. The proposed system has been experimentally verified, obtaining accurate time-domain waveforms and output power calculation.

Analysis and Design of a Single-Stage High-Power-Factor Dimmable Electronic Ballast for Electrodeless Fluorescent Lamp

A methodological study of an electronic ballast for electrodeless fluorescent lamps (EFLs) including design and development issues is presented in this paper. The ballast is intended to feed a 100-W EFL at 250 kHz with dimming feature. The proposed topology is composed of a single-ended primary-inductance converter, used as power-factor (PF)-correction stage, integrated with a resonant half-bridge inverter, used as lamp-power control stage. The integration of both stages is proposed in this paper, in order to reduce the number of active switches, as well as to simplify the required driving and control circuitry for this application. Experimental results demonstrate the feasibility of the proposed solution that achieves 54% lamp-power dimming (46 W). The implemented topology attained very high PF (0.989) and low line-current total harmonic distortion (14.929%), without using electromagnetic interference filter, while the measured efficiency was 87% at nominal lamp power.

Upgrading of double series‐resonant half‐bridge inverter to improve efficiency

Domestic induction cookers can have several heating areas, hence multiple-output topologies are commonly used. One of these multiple-output topologies is the double series-resonant half-bridge inverter. An upgrading of this topology is proposed. This upgrading consists of adding a relay to allow connecting the capacitor tanks in parallel. The aim of this upgrading is to increase the efficiency through the reduction of the device currents. The proposed upgrading topology has been tested by means of a prototype.

Novel Ozone Generation Power Supply using a Topology of the PFC DC-DC Boost Converter and Single-phase Half-bridge Inverter

최근 들어 살균과 특수세정의 용도로 오존발생 장비들이 많은 주목을 받으면서, 오존발생 전원공급장치에 대한 연구들이 활발히 진행되고 있다. 따라서 본 논문에서는 PFC DC-DC 부스트 컨버터와 단상 하프브리지 인버터 구조를 이용하여 기존의 오존발생 전원공급장치에 비해 제어가 용이하고 시스템을 소형화한 새로운 오존발생 전원공급장치를 제안한다. 제안하는 전원공급장치는 펄스폭변조(PWM; Pulse-Width Modulation) 기법을 이용하여 전력반도체스위치를 스위칭하여 동작함으로써 시스템 손실을 최소화한다. 본 논문에서는 제안하는 전원공급장치의 각 부분의 동작원리를 모드별로 설명하고, 프로토타입 전원공급장치의 컴퓨터 시뮬레이션 결과와 실험결과를 통해 제안한 전원공급장치의 우수한 특성을 입증한다.

Dual Half-Bridge DC–DC Converter With Wide-Range ZVS and Zero Circulating Current

A new converter topology that is both high power and digitally controlled combines two half-bridge inverters to operate as a full-bridge power stage using phase-shifting control, but with zero circulating current. Each power switch operates with a nominal 50% duty cycle to achieve zero-voltage switching over a widely varying load, but can also function in pulsewidth modulation mode for increased output voltage regulation range. Light-load efficiency can be improved by turning OFF one half-bridge inverter. A 1-kW 385-48 V converter designed to validate the concept achieved both 96+% efficiency and high power density.

Electric Equivalent Model for Induction Electrodeless Fluorescent Lamps

This paper presents an electric equivalent model applied to induction electrodeless fluorescent lamps. The model is based on passive components and takes into account the real and reactive lamp power. The presented model and its obtention methodology will be an important tool for ballast designers. One of the most important features of the proposed methodology is the concern regarding core losses and lamp reactive characteristics, because nowadays there are no electric models including these characteristics. In order to obtain and validate the electrodeless lamp model, a series-parallel resonant half-bridge inverter is used as ballast. Plasma and lamp windings are modeled as resistances and reactances depending on the lamp power. Simulations employing the proposed model are also presented, showing an excellent agreement with experimental results.

A Controlled-Type ZVS Technique Without Auxiliary Components for the Low Power DC/AC Inverter

This paper proposes a soft switching technique for dc/ac inverters, by using duty cycle and frequency modulation. Zero voltage switching (ZVS) is achieved through controlling the inductor current bidirectional in every switching cycle. This technique requires no additional resonant components and can be employed for various low power applications on conventional full-bridge and half-bridge inverter topologies. Three different current mode control schemes are derived from the basic theory of the proposed technique. They are referred to as boundary current mode (BCM), variable hysteresis current mode (VHCM), and constant hysteresis current mode (CHCM) in this paper and their advantages and disadvantages are compared. Simulation and experimental results demonstrate the feasibilities of the proposed soft-switching technique and its control schemes.

Design and Construction of Low Cost High Voltage dc Power Supply for Constant Power Operation

Pulsed load applications like laser based systems need high voltage dc power supplies with better regulation characteristics. This paper presents the design, construction and testing of dc power supply with 1 kV output at 300 W power level. The designed converter has half bridge switched mode power supply (SMPS) configuration with 20 kHz switching. The paper covers the design of half bridge inverter, closed loop control, High frequency transformer and other related electronics. The designed power supply incorporates a low cost OPAMP based feedback controller which is designed using small signal modelling of the converter. The designed converter was constructed and found to work satisfactorily as per the specifications.

Single-Phase Dual-Output Inverters With Three-Switch Legs

In this paper, two reduced switch count topologies are introduced for independently supplying two single-phase ac loads with one inverter. Using a new three-switch leg structure recently introduced and implemented in three-phase converters, two types of dual-leg and single-leg topologies are developed which respectively are functionally comparable to two full-bridge and half-bridge inverters working independently though with a less number of semiconductor switches and hence control and gate drive circuit components. The proposed six-switch and three-switch topologies are introduced; two modes of equal frequency and different frequency operation each of its own distinctive characteristics are considered for them and their pulse width modulation schemes are elaborated. Comprehensive analyses of power loss profile and output waveform properties are conducted via simulation for the proposed inverters, and the results are compared with full-bridge and half-bridge inverters. To assess the performance of the proposed inverter topologies, working prototypes are built, and the experimental results are provided.

Single-stage electronic ballast with high-power factor

This article proposes a single-stage electronic ballast circuit with high-power factor. The proposed circuit was derived by sharing the switches of the power factor correction (PFC) and the half-bridge LCC resonant inverter. This integration of switches forms the proposed single-stage electronic ballast, which provides an almost unity power factor and a ripple-free input current by using a coupled inductor without increasing the voltage stress. In addition, it realises zero-voltage-switching (ZVS) by employing the self-oscillation technique. The saturable transformer constituting the self-oscillating drive limits the lamp current and dominates the switching frequency of the ballast. Therefore, the proposed single-stage ballast has the advantage of high-power factor, high efficiency, low cost and high reliability. Steady-state analysis of the PFC and the half-bridge LCC resonant inverter are described. The results of experiments performed using a 30 W fluorescent lamp are also presented to confirm the performance of the proposed ballast.

Class-D/DE Dual-Mode-Operation Resonant Converter for Improved-Efficiency Domestic Induction Heating System

Induction heating (IH) technology is nowadays widely present in domestic appliances because of its cleanness, high efficiency, and faster heating process. All of these advantages are due to its heating process, where the pot is directly heated by the induced currents generated with a varying magnetic field. As a result, the glass where the pot is supported is not directly heated and, consequently, efficiency and heating times are improved. IH systems are based on dc-link inverters to generate the required alternating current to feed the inductor. Usually, resonant converters are used to achieve higher efficiencies and power densities. In such systems, the maximum output power and efficiency are achieved at the resonant frequency, and the switching frequency is increased to reduce the output power. As a consequence, in these converters, the efficiency is also reduced in the low-medium output power range. This paper proposes the use of the half-bridge inverter in two operating modes to achieve higher efficiency in a wide output power range. The power converter topology can be reconfigured by changing the resonant capacitors through electromechanical relays. As a consequence, the entire efficiency of the cooking process is improved with a cost-effective procedure.

Modulação Pwm de Baixa Frequência Aplicada à Topologia Integrada Sepic Meia-ponte para o Controle da Intensidade Luminosa de Lâmpadas Fluorescentes


 Este artigo apresenta o projeto e o desenvolvimento de um reator eletrônico para o acionamento de lâmpadas fluorescentes sem eletrodos, operando em 250 kHz. Neste, propõe-se a incorporação de um controle da intensidade luminosa da lâmpada, baseado em um sinal PWM modulado em baixa frequência. A topologia é baseada em um conversor SEPIC (Single-Ended Primary Inductance Converter), empregado como estágio pré- regulador de fator de potência (PFP), integrado a um inversor Meia Ponte Ressonante, utilizado como estágio de controle de potência (CP). A integração entre esses dois estágios é proposta neste trabalho, com o principal intuito de reduzir o número de interruptores ativos, aumentando assim a confiabilidade do reator eletrônico proposto. Resultados experimentais ratificam a viabilidade da solução proposta, a qual atingiu uma faixa de controle de potência de aproximadamente 74% (100 W até 26 W).

Experimental and Numerical Analysis of a Simple Core Loss Calculation for AC Filter Inductor in PWM DC-AC Inverters

This paper introduces a simple core loss calculation method for output filter inductor in pulse width modulation (PWM) DC-AC inverter. Amorphous C-core (AMCC-320) is used to analyze the core loss. In order to measure core loss of the output filter inductor and validate the proposed method, a single-phase half-bridge inverter and a calorimeter are used. By changing switching frequency and modulation index (MI) of the inverter, core loss of the AMCC-320 is measured with the lab-made calorimeter and the results are compared with calculated core loss. The proposed method can be easily extended to other core loss calculation of various converters.

Study and Development Inductance Melting Control System Using low Energy

This paper proposes a method study and development induction heating system using low energy the method was designed system by haft-bridge inverter circuit to the direct load of LC series resonant. The half-bridge inverter had been generating frequency on 47kHz and adjustable a pulse width modulation (PWM) which program by microcontroller power supply full-bridge 50 volt and overload current sensor by means of hall current sensor. The exemplar had an aluminum round bar diameter size 8 10 13mm. and 10mm. as long size. The method had provided heat aluminum while 6-9minute the small size of exemplar had melted fast more than extra size with use of current among 7.55-9.2 ampere is used minimum electric power of 377.5 watt and 461 watt as maximum. Comparison with other research used of power since 0.5-3 kilowatt have to from an isolated high frequency transformer had been losing power transfer more than direct resonant load wherewith the material have coincided of size.

The Application of SG3525 Pulse Width Modulator in Intermediate Frequency Induction Heating Power Supply

In This paper, we introduce a kind of intermediate frequency induction heating power supply integral design based on the pulse width modulator SG3525, analyse SG3525, KA962F driving chip, the main circuit structure and function and realize frequency and occupies emptiescompared independent can be adjusted. The main circuit adopts the series resonant type IGBT half bridge inverter circuit. It outputs pulse with difference of two phases of 180 degrees to the IGBT driver board through the SG3525, IGBT driver board receives the pulse and drive the IGBT main circuit. Circuit adds the limit frequency protection circuit design, so that the heating power supply works in the inductive state. To improve the on-site operation safety.Finally the unit circuit experiment is conducted on the basis of the field experiment, it is proved that the whole design scheme is feasibility by experiments.

Soft-Switching DC/DC Converter With a Full ZVS Range and Reduced Output Filter for High-Voltage Applications

A new soft-switching dc/dc converter, which can solve the drawbacks of existing phase-shifted full-bridge converters such as narrow zero-voltage-switching (ZVS) range, large circulating current, large duty-cycle loss, and a large output filter in high-voltage applications, is proposed in this paper. The proposed converter is composed of two symmetric half-bridge inverters that are placed in parallel on the primary side and are driven in a phase-shifting manner to regulate the output voltage. At the rectifier stage, two full-bridge rectifiers sharing two low-current-rating diodes are employed. This structure allows the proposed converter to have the advantages of a full ZVS range, no problems related to duty-cycle loss, no circulating current, and a significantly reduced output filter. In this paper, the circuit configuration, operation principle, and relevant analysis results of the proposed converters are presented. Experimental results on a prototype converter realized with the specification of 80-in plasma display panel sustain power module (320–385 V <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$_{\rm dc}$</tex> </formula> input, 205 V <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$_{\rm dc}$</tex></formula> /5 A output) validate the theoretical analysis.

Phase-controlled electronic ballast with dimmable linear and wide range features

This article presents the design and implementation of a phase-controlled electronic ballast system with dimmable linear and wide range features. The proposed system includes a TRIAC phase controller, a boost converter, a half-bridge inverter, and a system micro-controller. The firing angle of the phase controller is sensed as a reference to adjust the output voltage of the converter and switching frequency of the inverter to achieve linearity and wide range for dimming performance of the lamp. The modeling, analysis, and design of the phase-controlled electronic ballast are proposed in this article. The system controller is implemented using a low-cost 8-bit MCU and the designed system is practical in real world use. Hardware measurements have been presented to verify the usefulness of proposed control method of the two-stage electronic ballast in this article.

Double-Switch Single-Transformer Cell Voltage Equalizer Using a Half-Bridge Inverter and a Voltage Multiplier for Series-Connected Supercapacitors

Cell voltage equalizers are necessary to ensure years of operation for series-connected supercapacitors (SCs) by eliminating cell voltage imbalance. Conventional equalizers require numerous switches and/or magnetic components; hence, the circuit complexity and size tend to increase. In this paper, a double-switch single-transformer equalizer, which is based on the combination of a half-bridge inverter and a voltage multiplier, is proposed. The operation of the proposed equalizer is analyzed in detail, and a dc equivalent circuit is mathematically derived. Experimental equalization tests were performed for eight SCs connected in series under a voltage-imbalanced condition. The energy of the series-connected SCs was preferentially redistributed to SCs with low voltages, and eventually, the voltage imbalance was eliminated, demonstrating the equalization performance. Simulation-based equalizations using the derived dc equivalent circuit were also performed under the same condition as the experiments. The experimental and simulation results were in good agreement, indicating that the derived dc equivalent circuit can adequately express real equalization profiles.

An analysis of approaches to developing converters for power engineering based on vacuum switching-type electronic devices

The technical feasibility of using electron-beam valves of the EBV 2/200, EBV 4/40, and EBV 50/100 types in power electronic engineering, including static reactive-power compensators or integrated power-flow controllers, was considered at line voltages of 20–35 kV without using high-voltage transformers. A physical analog of bridge and half-bridge inverters on the basis of the EBV 4/40 valve with pulse-width modulation with a sampling rate of 1–2 kHz was built.

유도가열 시스템을 위한 새로운 전류형 풀-브릿지 공진형 인버터 설계

There are two types of inverters that are generally used in induction heating systems: voltage type inverters and high-frequency half-bridge inverters. This paper proposes a new resonant inverter for induction heating systems using the current type full-bridge method. The proposed method can remove capacitors at the input end, and enables unity power factor operation by preventing phase differences of voltage and current. Furthermore, Zero Voltage Switching (ZVS) which is in tune with current type inverter can be adopted and continuous power adjustment is possible through duty ratio changes and frequency modulation in switching operation. Simulations and experiments showed that the proposed current type full-bridge resonant inverter could be used for unity power factor control and ZVS operation in induction heating systems.