[Show abstract][Hide abstract] ABSTRACT: This paper presents a new ZCS-PWM high frequency inverter. Zero current switching operation is achieved in the whole load range by using a simple auxiliary reverse blocking switch in parallel with series resonant capacitor. Dual duty cycle control scheme is used to provide a wide range of high frequency AC output power regulation that is important in many high frequency inverter applications. It found that a complete soft switching operation can be achieved even for low power setting ranges by introducing high-frequency dual duty cycle control scheme. The proposed high frequency inverter is more suitable for consumer induction heating (IH) applications. The operation and control principle of the proposed high frequency inverter are described and verified through simulated results.
Preview · Article · May 2007 · Journal of power electronics
[Show abstract][Hide abstract] ABSTRACT: In the dissertation, a power conversion system for fuel cell is composed of a PWM inverter with LC filter in order to convert fuel cell voltage to a single phase 220[V]. In addition, new insulated DC-DC converters are proposed in order that fuel cell voltage is boosted to 380[V]. In this paper, it requires smaller components than existing converters, which makes easy control. The proposed DC-DC converter controls output power by the adjustment of phase-shift width using switch in the secondary switch which provides 93-97[%] efficiency in the wide range of output voltage. Fuel cell simulator is implemented to show similar output characteristics to actual fuel cell. Appropriate dead time td enables soft switching to the range where the peak value of excitation current in a high frequency transformer is in accordance with current in the primary circuit. Moreover, appropriate setting to serial inductance La reduces communication loss arisen at light-load generator and serge voltage arisen at a secondary switch and serial diode. Finally, TMS320C31 board and EPLD using PWM switching technique to act a single phase full-bridge inverter which is planed to make alternating current suitable for household
[Show abstract][Hide abstract] ABSTRACT: This paper proposes converter that new soft switching active snubber circuit is added, the resonance energy return to life rate doing maximum whole efficiency increase. Proposed converter adds auxiliary switch and resonance inductor, resonance capacitor, two diodes to existing converter, all switch elements play turn-on/turn-off under soft switching condition and minimized switching losses. Conduction loss department is that watch layer bringing back to life resonance energy by input perfectly. These result proved through simulation and an experiment.
[Show abstract][Hide abstract] ABSTRACT: We propose a power factor correction scheme using a LC resonant circuit in commercial frequency without switching devices. In this method, It makes a sinusoidal wave by widening conduction period using the current resonance in commercial frequency, Hence, the harmonic characteristics can be significantly improved, where the lower order harmonics, such as the fifth and seventh orders are much reduced. The result are confirmed by the theoretical and experimental implementations
[Show abstract][Hide abstract] ABSTRACT: The paper provides a novel method to start the linear engine coupled linear generator from dead stop to its final steady state operation. This method depends mainly to use the linear generator mounted on the shaft of the linear engine to provide the required thrust force to move and oscillate the linear engine from bottom to top dead centers. It is a cost effective approach to start the internal linear combustion engine using its coupled tubular permanent magnet linear generator proposed here. This linear generator operates in this case in motoring mode, providing the required thrust force by feeding this linear generator phases with currents by using a three phase PWM inverter controlled by position feedback scheme. In order to provide the desired thrust force with specific value and direction, a position feedback is required to control the free piston engine motion through controlling the inverter switches using PWM control scheme
[Show abstract][Hide abstract] ABSTRACT: A sterilizer equipment by using electrical energy has merits that have no process of chemical and no second environmental pollution. Moreover, the power conversion circuit for sterilizer equipment has merits that are reducing switching loss for soft switching topology by using zero current and zero voltage switching, and miniaturizing size of equipment. The proposed power device which has lower output current than other devices is possible to be compacted in its size and reduced its price if the proposed power device is used for power system. Therefore, it is adapted for both less power consumption and sudden power conversion
[Show abstract][Hide abstract] ABSTRACT: This paper presents a novel circuit topology of a high efficiency single-phase power conditioner. This power conditioner is composed of time-sharing sinewave absolute pulse width modulated boost chopper with a bypass diode in the first power processing stage and time-sharing sinewave pulse width modulated full-bridge inverter in the second power processing stage operated by time-sharing dual mode pulse pattern control scheme. The unique operating principle of the two power processing stage with time-sharing dual mode sinewave modulation scheme is described with a design example. This paper proposes also a sinewave tracking voltage controlled soft switching PWM boost chopper with a passive auxiliary edge-resonant snubber. The new conceptual operating principle of this novel power conditioner related to new energy utilization system is presented and discussed through the experimental results
[Show abstract][Hide abstract] ABSTRACT: This paper deals with a novel full bridge circuit topology of high frequency transformer isolated soft switching PWM inverter type DC/DC power converter. The zero voltage soft switching PWM DC/DC power converter employing an input DC rail series switch and parallel capacitor assisted by high frequency transformer parasitic component is proposed and developed for high performance TIG and MIG arc welding in industry. Its operating principle in stead state is described by introducing switching mode equivalent circuits. The operating performances of 32 V-300 A/60 kHz soft switching PWM inverter fed DC-DC power converter using IGBT module package are illustrated on the basis of experimental results along with its power loss analysis
[Show abstract][Hide abstract] ABSTRACT: A DC-DC converter is being widely used for various household appliances and for industry applications. The DC-CC converter is powered from single battery, and the voltage is varied according to the purpose. In the vehicle, various accessories whose electric power is different are being un4 Thus, plural number of DC-DC converter should be provided, so these situations bring complicated circuits, and accordingly, higher cost. Under such backgrounds, in this paper, we propose a novel buck-boost chopper circuit with simply configuration which can supply to two or more different output loads. The propose chewer circuit can control output voltages by controlling duty ratio by using typically two switching devices, which is composed by single boost-switch and single buck-switch. The output voltage can be controlled widely. A few modified circuits developed from the fundamental circuit are represented including the general multi-load circuit. And all this merits and appropriateness was proved by computer simulation and experience.