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This article describes a 3-kW simmer and 30-kV dc trigger power supply system for driving xenon flash lamps in large-area processes. Simmer power supply is designed to output maximum of 3 kV for maintaining the lighting state of the lamp after having triggered and to supply low ripple current continuously for maintaining the ignited state. It is designed based on an LCC resonant converter and design and implementation of the high-voltage transformer and output rectifier are presented. For igniting xenon lamps, dc trigger is designed to output a maximum of 30 kV auxiliary trigger voltage. The system that both power supplies is operated by one main inverter is presented. Through the resistive-load test, it is verified that the simmer outputs 600 V, 5 A under rated-load condition and 120 V, 1 A under light-load conditions. It is also verified that the simmer outputs 3 kV and the dc trigger outputs 30 kV under the no-load condition.Finally, the simmer and dc trigger power supply system is applied to lighting various xenon lamps from single lamp (306 mm, 8Φ) to three series lamps (400 mm, 26Φ). Required output voltages for stable driving various types of xenon lamps in the lighting mode are presented. [ABSTRACT FROM AUTHOR]

This article presents a bipolar pulse power modulator for high-efficiency production of plasma activated water (PAW). The proposed modulator is designed based on a power cell structure that has structural advantages of a power loop and control loop. Full-bridge based power cells are designed and 12 cells are connected in series. A power loop transformer is designed to deliver isolated power to all cells simultaneously without additional charging switches. A bipolar control loop structure is designed to supply the isolated power and signals required for 48 discharge switches through a pair of high voltage cables. The specifications of the modulator based on the proposed design produces a maximum output voltage and current of 10 kV/100 A, a pulsed width ranging from 0.6 to 10 μs, a maximum repetition rate of 3 kHz, and an average power of 2 kW. The bipolar modulator is tested under resistive and plasma reactor load conditions. In addition, a comparative experiment on the production efficiency of PAW between the proposed modulator and the existing modulator is performed under the same output power condition. Finally, the nitrate generation efficiency is 3.03 g/kWh, which is 1.7 times higher than the existing modulator. [ABSTRACT FROM AUTHOR]

This article describes a modification and an experiment conducted on a solid-state pulsed power modulator (SSPPM) for medical linear particle accelerator (LINAC) applications. Depending on the operating condition of the magnetron, an existing design of an insulated-gate bipolar transistor (IGBT)-based modulator is modified, from a positive pulse generator to a negative pulse generator. The design of the gate driver circuit of the pulse discharging IGBTs is also slightly changed to secure reliability against the arc condition. The developed modulator has the following maximum output—pulse voltage of −40 kV, pulse current of −100 A, pulsewidth of 5 μs, and pulse repetition rate of 250 Hz. By adapting the proposed design to the pulsed power modulator for driving the magnetron, high peak and average power densities of 43 kW/L and 48.9 W/L, respectively, can be achieved. The experimental results from various tests conducted using a resistor load, including a rated operation and an arc protection, verify the robustness and utility of the developed SSPPM for medical LINAC applications. An experiment using a 9.3-GHz 1.7-MW X-band magnetron is also conducted. The developed modulator achieved a successful arc protection operation for the arc generated in the waveguide during the magnetron drive test. [ABSTRACT FROM AUTHOR]

Conventional power supply systems for xenon lamps have only limited applicability in sintering, because sintering needs to drive the lamp itself as well as enable instantaneous and strong discharge of voltage and current for generating intense light. This implies that, for sintering applications, a method should be developed that would enable instantaneous and strong discharge of energy. In this paper, we propose a new xenon lamp sintering system with an additional capacitor charger and bank. The proposed system features three power supplies. Two power supplies, called the trigger and the simmer, ionize gaseous xenon using a 23-kV trigger pulse output and sustain the ionized xenon gas using a 2.5-kW simmer power supply. The used trigger is also specially designed to conduct high current through its transformer, and it makes the proposed system an outstanding high voltage blocking capability. Another 36-kW power supply charges a 130-mF capacitor bank with a high-efficiency resonant converter. In addition, some components such as the simmer blocking diode and the trigger output capacitor are introduced, because combining different power supplies causes operational problems. These components are analyzed with some circuits that show its features, and finally, the validity of the suggested system was confirmed in two steps. First, the simmer power supply and the capacitor charger were tested for the rated operating performance by using a resistive load condition. As a result, the rated operation of the simmer power supply was confirmed under the 2.5-kW output condition, and the efficiency of the capacitor charger was found to be greater than 96% at the rated 36-kW rated load condition. In addition, a pulse discharge current of 900 A was also observed with the equivalent resistor load through a pulsed discharge experiment of the capacitor bank, which was charged at 1500 V. The trigger power supply, whose equivalent resistive load was difficult to realize, was experimented directly using the real xenon lamp to check the stable trigger operation of the xenon lamp at its 23-kV output pulse voltage. After the verification using the resistive load condition, the real operation and performance of the combined xenon lamp power supply system that includes three kinds of power supplies were finally tested and verified by using the actual xenon lamp as a total system. [ABSTRACT FROM AUTHOR]