Soft Switching High Frequency Inverter Research Articles

位相差制御高周波ソフトスイッチングインバータの ZCS 回路方式と効率・制御特性

位相差制御高周波ソフトスイッチングインバータの ZCS 回路方式と効率・制御特性

A New Proposal of An Instantaneous Resonant Complex Current Vector Controlled High-Frequency Soft-Switching Inverter Topology for Induction Heating

A novel high-frequency resonant inverter operating under a complete zero current soft transition mode is originally proposed in this letter, which can be continuously controlled by regulating phase difference angle between two resonant currents under the fixed switching frequency. Its operating principle and unique features are described herein by simulation analysis for high-frequency low resistivity induction heating of metal vessels. Furthermore, its output power regulation vs. phase-shifted angle characteristics are demonstrated under the condition of complete ZCS operation.

Power Supply for Variable Frequency Induction Heating Using MERS Soft-Switching High Frequency Inverter

Variable frequency induction heating has great potential for industrial heating applications due to the possibility of achieving heating distribution control; however, large-scale induction heating with variable frequency has not yet been introduced for practical use. This paper proposes a high frequency soft-switching inverter for induction heating that can achieve variable frequency operation. One challenge of variable frequency induction heating is increasing power electronics ratings. This paper indicates that its current source type dc-link configuration and soft-switching characteristics can make it possible to build a large-scale system with variable frequency capability. A 90-kVA 150-1000Hz variable frequency experimental power supply for steel strip induction heating was developed. Experiments confirmed the feasibility of variable frequency induction heating with proposed converter and the advantages of variable frequency operation.

Cost effective phase shifted pulse modulation soft switching high frequency inverter for induction heating applications

A cost-effective high-efficiency high-frequency inverter with a PSM (phase-shifted pulse modulation) scheme is proposed for medium power (5–30 kW) induction heating applications. This inverter topology can achieve soft switching commutation in a wide range of power regulation, without an auxiliary active resonant snubber circuit. The high-frequency PSM control scheme presented can provide not only effective power regulation of the proposed inverter using IGBTs, but also soft switching commutation. Theoretical equations for the soft switching operation region are derived from the practical consideration of the gate pulse control strategy, in which the soft switching operation is limited only by the duration of dead time. Through experimental comparison of switching losses in the two-in-one IGBT power module, consideration is given to how much the effect of soft switching can improve actual efficiency. In this discussion, the cost effective high-efficiency inverter circuit topology is realised. The proposed inverter accomplishes soft switching operation over a wide power regulation range. The actual power conversion efficiency reached was 96.7%.

A Novel Type of Series Load Resonant High Frequency Soft Switching Inverter with Phase Shift Control Scheme

The voltage source full bridge series load resonant high frequency soft switching inverter using pulse phaseshift modulation (PSM) strategy is proposed, which can operate ZVS in the left hand side bridge leg and ZCS in the right side bridge leg. This inverter using IGBTs employs two passive components and does not need any additional auxiliary circuit for the active power switch to achieve soft switching commutation, and it has wide soft switching operation region from full power to 3% light power. Furthermore, constant frequency power regulation that is required for induction-heating power applications is introduced on the basis of PSM. In this paper, steady state switching modes of the inverter treated here and its power regulation scheme by PSM are described under a soft switching scheme. Because the proposed inverter can operate at series resonant frequency of series resonant circuit under soft switching condition, it is easy to design the value of series resonant capacitor. The design methods of loss-less snubbing circuit components for soft switching are described to reduce switching losses effectively. The feasible experiment of the proposed inverter is implemented to demonstrate the power regulation performance of proposed high frequency inverter, high efficiency 97.6% at full power condition is obtained.

Quasi-series-resonant-type soft-switching phase shift modulated inverter

A prototype of a series-load resonant and quasi-resonant hybrid-type soft-switching high frequency inverter is proposed for induction heating applications, together with its operating principle. The bridge legs of the inverter treated here have the salient feature of a power regulation function under a constant switching frequency which is based on pulse phase shift modulation due to the current leading leg and the current lagging leg. Because quasi-resonant current flowing through each active power switch becomes a trapezoidal waveform or quasi-square waveform due to the quasi-series resonant operation, it is expected that the conduction loss increase by the peak current through each power semiconductor switching device in the full bridge arm be basically suppressed as compared with that of the conventional series load resonant high frequency inverter. The design procedure of circuit components to achieve a soft-switching of this high frequency inverter, the reduction effect of switch peak voltage stress and its power regulation performance are described and discussed in detail. The effectiveness of the 5 kW–21 kHz soft-switching pulse phase shift modulated high frequency inverter using the IGBT power modules is proved on the basis of the power regulation performance and power conversion efficiency.

Constant Frequency Time Ratio Pulse Modulation Series Resonant using A Single Auxiliary Active Power Switch

In this paper, the time ratio pulse modulation type series resonant soft switching high frequency inverter using a single auxiliary active power switch is presented, which includes zero current soft switching-assisted lossless inductors, along with its output power regulation characteristics under the condition of a constant operation frequency and complete soft commutation.

Latest Development of Involuted Type Induction Heated Hot Water Producer Using ZVS-PWM High Frequency Inverter

This paper presents a new conceptual electromagnetic induction eddy current-based involuted type heat exchanger for hot water producer and boiler, which are suitable and acceptable for consumer power application. In addition, an edge-resonant PWM high frequency inverter using IGBTs can operate under a principle of zero voltage soft commutation is developed and demonstrated for an induction heated hot water producer and boiler.This innovative consumer power electronic appliance using high frequency soft switching inverter is discussed and evaluated on the basis of simulation and experimental results.

Zero Current Soft-Switching High Frequency Inverter with PDM Control Scheme for Induction Heating Roller

This paper presents an inductor snubber -assisted high frequency series resonant inverter for induction eddy current-heated roller in copy and printing machines, which can achieve ZCS and wide power regulation under constant frequency pulse density modulation. Its operating principle is presented, together with its output power regulation characteristics.

Soft-switching inverter for electrodynamic shaker

The paper presents the design and implementation of a soft-switching inverter with zero voltage transition (ZVT) for shaker armature excitation. First, the circuit configuration and the operation principle of the proposed inverter are introduced in detail. A quantitative design procedure is developed according to the governed equations derived in various operation modes for finding the values of soft-switching circuit components. Then the implementation of the switching control circuit for the successful operation of the proposed soft-switching scheme is described. Finally, the performance of the shaker table fed by the designed soft-switching high frequency inverter is demonstrated by some simulation and measured results. The results show that less switching loss and switching stress of the inverter switch are obtained by the proposed soft-switching scheme.