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Applications of Soft-Switching Full-Bridge Converter and Rotational Electric Field to Transdermal Drug Delivery
No full text[[abstract]]This paper presents applications of a soft-switching full-bridge converter to generate pulsed voltage (PV for exciting tissue, which includes transdermal drug delivery (TDD), transcutaneous electrical nerve stimulation, functional electrical stimulation, etc. Particularly, in TDD it offers many potential advantages over conventional methods, such as oral and injection, and it avoids drug degradation through gastro-intestinal and liver. To design a portable driving system with battery source, the proposed converter is equipped with a soft-switching cell to achieve zero voltage switching or zero current switching, improving efficiency about 20%. The overall system needs only a set of soft-switching cell to achieve soft-switching feature even though there are N sets of PVs, reducing size and cost significantly. Moreover, a rotational electrical field concept is introduced to further improve effectiveness of drug delivery. Experimental results of a 150 V output voltage and 18 W peak power have demonstrated the feasibility of the proposed converter.[[fileno]]2030197030112[[department]]電機工程學
Analysis and Design of a Battery Charger with Interleaved PFC based on an Asymmetrical Half-Bridge Topology
No full text[[abstract]]In this paper, analysis and design of a zero voltage switching (ZVS) isolated single-stage charger with interleaved power factor correction (PFC) based on an asymmetrical half-bridge topology is presented. The proposed charger is formed from an interleaved PFC converter and an asymmetrical half-bridge converter. It has the features of constant frequency operation, ZVS and low voltage stress imposed on the active switches. Moreover, it can achieve high power factor, high power density, high efficiency, low switching loss and low component count, which make converter operation at medium power levels feasible. In the paper, theoretical analysis and experimental results of a charger with the proposed topology have verified that power factor (PF) and total harmonics distortion (THD) can be significantly improved. In addition, input current ripple can be also reduced which in turn can reduce the size of line filter. The proposed charger is attractive for electric vehicle (EV) applications.[[fileno]]2030197030122[[department]]電機工程學
Design and Implementation of Electronic Dimming Ballasts Supplied by Photovoltaic System
No full text[[fileno]]2030197030183[[department]]電機工程學
A PSpice Model for Fluorescent Lamps Operated at High Frequencies
No full text[[abstract]]A PSpice circuit model simulating the electrical characteristics of the fluorescent lamp operated at high frequency is proposed. The model is constructed from a two-parameter equation which is derived based on a set of two measurements. This is a readily constructed and a computer simulator oriented model which is suitable for a preliminary design of electronic ballasts. Simulated and experimental results are used to verify the analytical discussions, and, moreover, an electronic ballast design example using the proposed model is presented to further demonstrate its applications.[[fileno]]2030197030201[[department]]電機工程學
Analysis and Design of Variable Frequency and Phase-Shift Controlled Series Resonant Converter Applied for Electric Arc Welding Machines
No full text[[abstract]]This paper presents the analysis and design of a variable frequency and phase-shift controlled series-resonant power converter applied as a power source for an electric arc welding machine with output ratings of 30 V and 130 A. The main switches of this power converter always hold zero-voltage switching (ZVS) from very light to full load. The conventional filter inductor is removed so as the assumption of a constant current sink is no longer valid, thus complicating the analyses dramatically. The operational principles of the power converter applied in a welding machine design are described in detail from which the voltage and current stresses imposed on the main components can be, therefore, derived and the design procedure can also be outlined. Computer simulations and experimental results obtained from a laboratory prototype are illustrated to confirm the analytical work.[[fileno]]2030197030202[[department]]電機工程學
The Central -Limit Control and Impact of Cable Resistance in Current Distribution for Parallel-Connected DC-DC Converters
No full text[[abstract]]A current-sharing technique known as central-limit control (CLC) is presented. Different design options of the CLC are discussed. An evaluation of the CLC technique, taking into account the converter cable resistance, is performed by large signal simulations. The simulation data shows that the CLC technique produces desired current-sharing at all load conditions with minimal degradation of the voltage loop-gain, resulting in excellent output voltage regulation. Large and small signal frequency response of the current-sharing loop-gains are analyzed for different cable resistance values, and it is shown that proper converter cable resistance greatly improves the performance of the CLC and enhances the parallel-connected DC-DC converter system stability.[[fileno]]2030197030206[[department]]電機工程學