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Interleaving Control Schemes for Critical-Mode Boost PFC
No full text[[abstract]]Interleaving control schemes are widely used in converter applications. Merits of such control methods are to reduce the input/output current or voltage ripples and volume, and to increase the processed power capacity of converters. For converters with constant operation frequency, it is easy to achieve interleaving control. However, it is difficult to realize interleaving features with variable operation frequency, such as boost-type power factor correctors (PFCs) operated in critical-mode (CM) condition. This paper proposes several interleaving controllers for CM boost PFCs. Analysis and design of the interleaving controllers are first described in detail. Moreover, simulated results of CM boost PFCs with two-phase and four-phase interleaving controllers are introduced. Finally, experimental results of a two-phase interleaved CM boost PFC are presented to verify the discussed features.[[fileno]]2030197030051[[department]]電機工程學
A Combined Wide and Narrow Pulse Generators for Processing Microbes
No full text[[abstract]]This paper proposes a wide pulse combined with narrow pulse generator for solid food sterilization. The proposed generator is composed of a full-bridge converter in phase-shift control to generate high dc-link voltage, and a full-bridge inverter associated with an L-C network and a transformer to generate wide pulses combined with narrow pulses. These combined pulses can prevent undesired strong air arcing in free space, reduce power consumption and save power components, while can sterilize food effectively. The converter and inverter can be operated at high frequencies and with PVM control, thus its weight and size can be reduced significantly and its efficiency can be correspondingly improved. Experimental results obtained from a prototype with +/- 10 kV wide pulses combined with +/- 10 kV narrow pulses and with 10 similar to 50 kW peak output power, depending on pulse width of the output pulses, have demonstrated its feasibility.[[fileno]]2030197030096[[department]]電機工程學
Multi-Phase Multi-Lamp Driving System for LCD Back Light
No full text[[abstract]]This paper presents a multi-phase multi-lamp driving system for liquid ctystal display (LCD) back light. The driving system adopts a multi-phase inverter to drive cold cathode fluorescent lamps (CCFL) to reduce input current ripple. Furthermore, to prevent current imbalance among lamps a multi-phase transformer is introduced in the proposed system. Compared with the conventional single-phase driving system, the proposed one can have the merit of requiring less number of transformers. A three-phase driving system with current balancing transformer has been built, from which experimental results have verified the feasibility of the proposed multi-phases driving system.[[fileno]]2030197030108[[department]]電機工程學
Microprocessor Controlled Electronic Ballast for Metal Halide Lamp
No full text[[fileno]]2030197030182[[department]]電機工程學