A5052789956- Gyrotron and Vacuum Electronics Research
- Particle accelerators and beam dynamics
- Pulsed Power Technology Applications
- Wireless Power Transfer Systems
- Particle Accelerators and Free-Electron Lasers
- Electrostatic Discharge in Electronics
- Advanced DC-DC Converters
- Plasma Applications and Diagnostics
- GaN-based semiconductor devices and materials
- Underwater Vehicles and Communication Systems
- Multilevel Inverters and Converters
- Advanced Algorithms and Applications
- Embedded Systems and FPGA Design
- Plasma Diagnostics and Applications
- Electromagnetic Launch and Propulsion Technology
- Energy Harvesting in Wireless Networks
- Radio Frequency Integrated Circuit Design
- Power Systems and Renewable Energy
Pohang University of Science and Technology
2002-2009
Pohang Accelerator Laboratory
2003-2009
In designing a compact and high efficiency TWT microwave amplifier, the role of power density DC supply is very important. order to reduce volume supply, it necessary increase switching frequency supply. The operation mainly reduces transformer in However, step-up ratio voltage needs be maintained. Therefore, pulse should carefully designed fulfil its function A designed, fabricated, tested. Switching 100 kHz. Input output voltages are 250 V 4 kV, respectively. Normal 3 kW. Maximum 400...
Pulse transformers suitable for high-frequency and high-voltage operations in a traveling-wave tube amplifier (TWTA) had been designed, fabricated, tested. Two with different operation frequency of 100 80 kHz were The transformer 100-kHz switching input output voltages 250 Vdc -4.1 kV, respectively. Operating power was 3.06 kW. Achieved density the 22.26 W/cm/sup 3/. 80-kHz 265 Normal operating 1.67 12.15 Three winding arrangements tested it found that one sandwiched primary between...
We designed a Marx generator for repetitive applications. The has 25 stages. Each stage was constructed 4 door knob ceramic capacitors and ball spark gap switch. used the inductor charging method higher operation. maximum output voltage of is 1 MV at open circuit condition. overall size 150 cm in length 60 diameter. tested different load conditions. present results test characterize generator.
Summary form only given. We designed a compact repetitive Marx generator. The generator contains 25 stages consisted with capactor banks and spark gap switches. used door knob ceramic capacitors. capacitors are charged through inductors by capacitor charging power supply. length the diameter of about 150 cm 60 cm, respectively. conducted preliminary test at condiction low voltage using helium gas. present characteristic discuss design issues such as insulation high feedthrough.
A pulse transformer for a high frequency and voltage operation had been designed, fabricated, tested. The of the increases power density. Therefore, it is possible to reduce supply volume. To produce output, should have step-up ratio. ratio generally limited in transformers due stray capacitance leakage inductance. limit was overcome by winding multi-secondary outputs. Switching 80 kHz. Input output voltages were 265 VDC 4.1 kV, respectively. Normal 1.7 kW. Maximum volume 200 cm/sup 3/....
The 2-GeV electron linac at Pohang accelerator laboratory (PAL) has been operated continuously as a full energy injector for the Light Source (PLS) since Dec. 1994. There have continuous efforts to improve klystron-modulator (K&M) system make it more stable and reliable. To self-diagnostic, operation, monitoring, remote communication, we developed new modulator controller based on an industrial PC platform. mainly consisted of interlock signal conditioning module, fast pulse...
It is beneficial to use a resonant pulse transformer charging circuit for designing of high voltage generator. A triple generator designed. air core used in the circuit. Triple with step up primary voltage. The step-up ratio designed as about eleven at stage. distributed forming network (PFN) form square output waveform. has an over-volted spark-gap switch that transfers energy matched resistive load PFN. positioned cylindrical oil tank. Height and diameter tank are respectively 1.06 m 1.28...
In this study, a high-efficiency wireless power transfer (WPT) coil that is robust against interoperability and misalignment was developed by applying an inductive system to drone. The transmitting had ferrite plate applied helical structure included the receiving part. guard-type part sheet. To analyze spiral coils according winding method, z-axis magnetic field vector analyzed. A suitable WPT model for each drone analyzing mutual inductance based on whether attached transmitter or receiver...
The role of a high power density DC supply is very important in designing compact and efficiency TWT microwave amplifier. In order to fabricate supply, it necessary reduce transformer volume by increasing switching frequency the supply. However, step-up ratio voltage could not be indefinitely increased due mainly self-resonance stray capacitance leakage inductance. Therefore, pulse should carefully designed fulfill its function A designed, fabricated, tested. Switching 100 kHz. Input output...
It is our interest to design and develop a high power pulser system employing microplasma discharge in spark gap system. The type of generates short electric pulses capable both the characteristics repetition rate fast rise time. Such switch has wide applications industry. An efficient electrical very important for switching operation. regime operation utilizes residual plasma inter pulse recovery increase rate. Therefore, mechanisms controlled manner, such as by arc channel, dielectric...
Pohang Accelerator Laboratory Linac magnet power supply (MPS) has been upgraded for the stable beam injection and 4 generation light source research, in 2006. MPSs are developed as compact configuration by using four quadrant switching scheme with MOSFET. In case of 10 V, +/-10A bipolar output operation, main circuit is operated one or three quadrant, 50 A unipolar parallel quadrant. Switching frequency MOSFET switch above than 40 kHz. MPS consists board, control regulator board CPU board....
Linear accelerator and Beam Transfer Line magnet power supply (MPS) in Pohang Accelerator Laboratory have been upgraded from convention scheme to switching for the stable beam injection 4 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> generation light source research. New MPS consists of two-main board (MPB), which are regulator, CPU control boards. The size each is only 100 mm times 240 mm. MPB full-bridge switch. functions one that...
Summary form only given, as follows. In designing a compact and high efficiency TWT microwave amplifier, the role of power density DC supply is very important. order to reduce volume supply, it necessary increase switching frequency supply. The operation mainly reduces transformer in However, step-up ratio voltage needs be maintained. Therefore, pulse should carefully designed fulfill its function A designed, fabricated, tested. 80 kHz. input output voltages are 265 V 4 kV, respectively....
High accuracy and stability digital controlled power supply for magnet (DigCon-MPS) is developed at PLS. This has three sections. The first section controller including DSP&FPGA precision ADC, the second consists of IGBT driver four quad switch, third LC output filter section. AC input voltage 3-phase 21V, current 0 ∼ 150 A dc. Switching frequency switch 25 kHz. very high 100 μA step resolution full range +/-1.5 ppm short term +/-5 long term. paper describes characteristics performance...