• 전기학회논문지
• /
• 제65권12호
• /
• pp.1992-1999
• /
• 2016

The plasma process is applied to various industrial fields such as high-tech IT industry, textiles and medical. Therefore, there is increasing interest in the plasma power supply, and demand for power devices of high efficiency and high power density is increased. Plasma power supply for process must solve the arc problem, when the plasma is unstable. The output capacitor is closely related to the arc problem. If the output capacitor is smaller, the damage from the arc problem is reduced. However, the small value of the output capacitor affects the operating characteristics of the power supply. In this paper, a LLC resonant converter is adopted, because it can achieve high efficiency and power density in the plasma DC power supply. However, due to the small value of the output capacitor, the converter is operated as a LLCC resonant converter. Therefore, a gain characteristic of LLCC resonant converter is analyzed by using the FHA (First Harmonic Approximation) in plasma power supply. Simulation and experimental results are presented to verify the characteristic analysis of LLCC Resonant Converter.

• 전기학회논문지P
• /
• 제61권3호
• /
• pp.116-121
• /
• 2012

Recently, in the field of renewable energy such as solar cells including the semiconductor and display industries, thin film deposition process is being diversified. Furthermore, to deal with trend of making high-quality and fast, the high-capacity and output plasma power supply which can control high density plasma is required. The biggest problem is arc discharge caused by using high voltage power supply. Thus, the key function of plasma power supply is to prevent arc discharge and there is a need to maintain the possible minimum arc energy. In DC sputtering power supply, on a periodic basis (-)voltage powering up is able to significantly reduce arcing, as well as arc discharge prevention, and maintaining uniform charge density. This conventional method for powering up (-)voltage requires heavy mutual inductance of the transformer to avoid distortion problem of the output voltage. This study is about energy recovery circuit for arc discharge prevention in sputtering plasma power supply. By using energy recovery circuit, it is possible to reduce the mutual inductance and size of the transformer dramatically, prevent distortion of the output voltage and has a stable output waveform. This work was proved through simulation and experimental study.

• 산업기술연구
• /
• 제27권A호
• /
• pp.157-162
• /
• 2007

This paper describes a power supply aimed at the production of plasma and its control method for a magnetron sputter in thin film coating process of PVD(Physical Vapor Deposition). Plasma load changes its impedance characteristic easily according to operating conditions and frequently produces electric arc. So. in this paper, a plasma power supply with improved output control performance in the transient state for the plasma load is presented. Also, it includes a strategy that can detect arc rapidly and reduce arc energy effectively into a load. The validity of the proposed power supply through experimentation on 20kW system was proved.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2014년도 추계학술대회 논문집
• /
• pp.85-86
• /
• 2014

The paper presents a power supply of atmospheric-pressure plasma reactor based on SiC (Silicon Carbide) MOSFET resonant inverter. Thanks to the capacitive characteristic of capacitive coupling plasma reactor type, the LC series resonant inverter had been applied to take advantages of this topology with the implementation of SiC MOSFET power modules as switching power devices. Designation of gate driver for SiC MOSFET had been introduced by this paper. The 5kVp, 5kW power supply had also been verified by experimental results.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 B
• /
• pp.1205-1207
• /
• 2004

AC plasma power supply is used to control a ozone generator and a air pollution gas. AC plasma power supply is composed of power semiconductor switch devices and control board adapted SHE(Selected Harmonic Elimination) PWM method. AC plasma power supply with sinusoidal VVVF(variable voltage and variable frequency) is realized. Its output voltage range is from 0 [V] to 20[kV] and output frequency range is from 8[kHz] to 20[kHz]. Using proposed system, AC high voltage and high frequency discharge is tested in the DBD(dieletric barrier discharge) reactor, and the space distribution of a its non-thermal plasma is observed. In spite of the increasement of voltage and frequency, the proposed system have a stable operation characteristics. It is verified by the experimental results.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
• /
• pp.113-116
• /
• 2001

In this paper, the development of the LF power supply for dry scrubber is discussed. 1500kW, 100kHz LF power supply is designed and tested. The main power stage is used for the FB PWM inverter with an LC filter in the secondary circuit. The operation characteristics of LF power supply are verified by simulation and experimental results.

• 한국대기환경학회지
• /
• 제16권3호
• /
• pp.247-256
• /
• 2000

Basic characteristics of non-thermal plasma process to remove C2H4 and NO have been experimentally investigated with a packed-bed type reactor and an ac power supply. The performance of the non-thermal plasma generated by ac power supply was compared with that of a wire-plate type reactor equipped with a pulsed power supply. The result shows that the non-thermal plasma can be effectively generated with an AC power supply that can be easily fabricated with conventional techniques. In order to understand the basic reaction mechanisms of the non-thermal plasma process, parametric tests for different carrier gases(air and nitrogen) and for different reaction pathways have been performed. The test results show that O3 generated by non-thermal plasma plays an dominant role to oxidize C2H4 and NO over N and O radicals when these pollutant gases are carried by dry air under room temperature condition. Experimental observations, however, indicate that N and O radicals can significantly affect on the removal process of the pollutant gases under certain conditions.

• 전력전자학회논문지
• /
• 제14권1호
• /
• pp.72-81
• /
• 2009

본 논문에서는 대기압 플라즈마 발생용 정현파펄스형 교류 전원 장치에 대한 연구를 진행하였다. 정현파펄스형 전원장치는 기존의 LC공진을 이용한 교류 전원장치보다 높은 dv/dt를 갖게 되므로 안정적인 플라즈마 공급이 가능하며 펄스형에 비해 고조파 노이즈가 적고, 정전류 턴온-영전압 턴오프 형태로 동작하므로 매우 높은 효율을 갖는다. 또한 플라즈마 점화 기능을 강화하고 안정적인 전압제어를 위해 3상 부스트형 컨버터를 입력단에 사용하여 입력 역률이 매우 높은 시스템을 구성할 수 있다. 실험실 수준의 10kW부하시설을 사용하여 본 연구의 결과를 입증하였다.

• 전력전자학회논문지
• /
• 제6권5호
• /
• pp.394-399
• /
• 2001

반도체 생산 공정에 있어, 저압 화학적 기상 증착(Low Pressure Chemical Vapor Deposition)과 프라즈마 강화 화학적 기상 증착(Plasma Enhanced Chemical Vapor Deposition) 공정 후 발생된 환경 유해 가스를 효과적으로 세정하기 위한 장비인 건식 세정기(dry scrubber)의 전원장치에 대한 연구이다. 주 전력회로는 1500W, 스위칭주파수 100kHz의 위상 변위 풀 브리지(Phase Shift Full-Bridge)방식의 인버터와 100kHz 저역 통과 필터 및 임피던스 변환기로 구성되었다 모드해석과 모의실험을 통하여 회로방식의 타당성을 확인하였고 50$\Omega$ dummy load 및 chamber 실험을 통하여 다양한 부하조건에서도 프라즈마를 안정되게 발생시킬 수 있음을 확인하였다.

• 전력전자학회논문지
• /
• 제21권6호
• /
• pp.514-524
• /
• 2016

This work suggests a study on 5 kW plasma power supply design and reactor capacitance estimation algorithm for a wide range of linear output control to operate a plasma reactor. The suggested study is designed to use a two-stage circuit and control the full-bridge circuit of the two-stage circuit using the buck converter output voltage of the single-stage circuit. The switching frequency of the full-bridge circuit is designed to operate through high-frequency switching and obtain maximum output using LC parallel resonance. Soft switching technique(ZVS) is used to reduce the loss caused by high-frequency switching, and duty control of the buck converter is applied to control a wide range of linear output. The internal capacitance of the reactor cannot easily be extracted, and thus, the reactor cannot be operated in an optimized resonant state. To address this issue, this work designs the internal capacitance of the reactor such that estimations can be performed with the developed reactor capacitance estimation algorithm applied to the internal capacitance of the reactor. A 5 kW plasma power supply is designed for a wide range of linear output control, and the validity of the study on the reactor capacitance estimation algorithm is verified.