관형 코로나 방전전극을 이용한 이온풍속의 최대화

정재승(Jae-Seung Jung),문재덕(Jae-Duk Moon) 대한전기학회 2010 전기학회논문지 Vol.59 No.12

A corona discharge system with needle point or wire type corona electrode has been well used as an ionic wind blower. The corona discharge system with a needle point electrode produces ions at lower applied voltage effectively. However, the corona discharge on the needle point electrode transits to the arc discharge at lower voltage, and it is hard to obtain the elevated electric field in the discharge airgap for enhancing the ion migration velocity due to the weak Coulomb force. A cylindrical corona electrode with sharp round tip is reported as one of effective corona electrode, because of its higher breakdown voltage than that of the needle electrode. A basic study, for the effectiveness of cylindrical electrode shape on the ionic wind generation, has been investigated to obtain an maximum wind velocity, which however is the final goal for the real field application of this kind ionic wind blower. In this paper, a parametric study for maximizing the ionic wind velocity utilizing the cylindrical corona electrode and a maximum ion wind velocity of 4.1 ㎧ were obtained, which is about 1.8 times higher than that of 2.3 ㎧ obtained with the needle corona electrode from the velocity profile.

전극형상 및 보이드에 따른 XLPE의 부분방전 특성

신종열,김균식,홍진웅,Shin, Jong-Yeol,Kim, Guin-sik,Hong, Jin-Woong 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.1

Transmission equipment is mainly used for the XLPE (cross-linked polyethylene) insulation cable for ultra high voltage power to minimize power loss. The experiment examined the partial discharge characteristics according to the insertion of the bar electrode and needle electrode into the XLPE specimen and the air voids. XLPE insulation cable manufactured by T. company and tungsten electrode material by K. company were used for specimens, by adhering conductive tape on the semi-conductive material of the lower electrode of XLPE specimen with the dimension of $16{\times}40{\times}30$ [mm] was used as negative electrode. In order to investigate the PD with ${\phi}$-q-n of XLPE specimen according to the electrode shape and the size of air voids. we examined the PD by varying the voltage after applying voltage of 3~20 kV on the electrode. Therefore, it was confirmed from the result of PD characteristics of specimen that the larger the air void than the gap between electrode (+) and electrode(-), the larger effect on the discharge when the bar electrode and needle electrode inserted into XLPE, and the closer the distance between the insulation and the needle electrode, the faster insulation breakdown.

Characteristics of Partial Discharge Inception Voltage for Electrode-Bound Voids According to Electrode Materials

Yoon Sungho,Son Hyeongwook,Kim Jeongtae,Kim Donguk 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

In this study, experiments and theoretical analyses were performed on the partial discharge initiation voltage of the electrode–bound void according to various electrode materials, including the semi-conductive rubber in the joint box of the high voltage power cable. Electrode–bound void specimens using Brass, Al, Cu, SUS and EPDM semiconducting rubber were prepared, and PDIV (partial discharge inception voltage) was measured and analyzed at 25, 60 and 90 °C. As a result, it was found that the PDIV of the electrode–bound void is dependent on the work function of the electrode. It was possible to interpret the measurement results through the calculation of the discharge voltage using Paschen’s law in combination with the thermionic emission of the electrode and thermal expansion of materials. In addition, in the case of the EPDM semiconducting rubber electrode, it was analyzed that the measured PDIV was lower than the calculated value because the void thickness was reduced due to elasticity.

정전 고속 미스트 엘리미네이터의 포집 효율 특성

김진선,김학준,한방우,우창규,김용진,이상린,문상철,Kim, Jin-seon,Kim, Hak-Joon,Han, Bangwoo,Woo, Chang Gyu,Kim, Yong-Jin,Lee, Sangrin,Moon, Sangchul 한국입자에어로졸학회 2018 Particle and Aerosol Research Vol.14 No.4

In this study, we developed a flat-plate type wet electrostatic precipitator that generates stable corona discharge compared to wire type discharge electrode. In order to compare the particle removal efficiency according to the shape of the discharge electrode such as the variation of the horizontal and vertical distance between spiked edges, and the variation of the height of discharge pin support were tested. As a result, when the horizontal distance between spiked edges was increased up to 36 mm, the vertical distance between spiked edges was increased up to 54 mm, and the height of the discharge pin support was increased up to 76 mm, the removal efficiency of PM10 was maintained at approximate 60.0%. Furthermore, the removal efficiency of particles over $5{\mu}m$ was about 80% or more. When the flow rate was 4 m/s, the gap between collection plates was 60 mm, and -14 kV was applied to the discharge electrode. The particle removal efficiency of the flat-plate type electrostatic precipitator was maintained when the horizontal and vertical distance between spiked edges, and the height of the discharge pin support was below a certain level. Those variables may be the important design factors for the shape of the discharge electrode. Therefore, when designing the electrostatic precipitator with multiple channels, the horizontal and vertical distance between spiked edges, and the height of discharge pin support must be selected in consideration of the weight of the discharge electrode and the processing cost.

AC PDP에서 공통전극에 펄스인가에 의한 플라즈마 방전의 시뮬레이션 결과

조병권 ( Byung Gwon Cho ) 한국화상학회 2015 한국화상학회지 Vol.21 No.4

The plasma discharge are simulated and the light waveforms are measured to shorten the address discharge time during an address period in AC PDP when the additional pulses are applied to the common electrodes during an address period. The wall charges in a cell are accumulated on three electrodes during a reset period in AC PDP and those are utilized to produce the triggering for the address discharge between the scan and address electrodes during an address period. However, as the negative charges cannot be utilized by the DC bias voltage on the common electrode in the conventional driving method, it is difficult to shorten the discharge delay time. If the negative charge on the common electrodes as well as the charges on the scan and address electrode are utilized, the address delay time can be shortened. In this study, the Xe 3P2 energy state to generate the vacuum ultraviolet are simulated when the scan and address pulses on two electrode are applied including the additional pulses on the common electrodes. In addition, the address discharge light waveforms in the conventional and the proposed driving method are measured.

미세 방전 가공에서의 방전 펄스 카운팅을 이용한 간극 제어

정재원(J. W. Jung),고석훈(S. H. Ko),정영훈(Y. H. Jeong),민병권(B. -K. Min),이상조(S. J. Lee) 한국정밀공학회 2006 한국정밀공학회 학술발표대회 논문집 Vol.2006 No.5월

The electrode wear in micro-EDM significantly deteriorates the machining accuracy. In this regard, electrode wear needs to be compensated in-process to improve the product quality. Therefore, there are substantial amount of research about electrode wear. In this study a control method for micro-EDM using discharge pulse counting is proposed. The method is based on the assumption that the removed workpiece volume is proportional to the number of discharge pulses, which is verified from experimental results analyzing geometrically machined volume according to various number of discharges. Especially, the method has an advantage that electrode wear does not need to be concerned. The proposed method is implemented to an actual micro-EDM system using high speed data acquisition board, simple counting algorithm with 3 axis motion system. As a result, it is demonstrated that the volume of hole machined by EDM drilling can be accurately estimated using the number of discharge pulses. In EDM milling process a micro groove without depth variation caused by electrode wear could be machined using the developed control method. Consequently, it is shown that machining accuracy in drilling and milling processes can be improved by using process control based on the number of discharge pulses.

3전극이 부설된 틈새 장벽방전형 플라즈마장치의 코로나 방전 및 오존발생 특성

文在德(Jae-Duk Moon),鄭在勝(Jae-Seung Jung) 대한전기학회 2007 전기학회논문지 Vol.56 No.3

Corona discharge and ozone generation characteristics of a slit dielectric barrier discharge type wire-plate plasma reactor with a third electrode have been investigated. When a third electrode is installed on a slit of the slit barrier, where an intense corona discharge occurs, it is found that a significantly increased ozone output could be obtained. This, however, indicates that the third electrode can activate the corona discharges both of the discharge wire and the slit of the slit barrier in the plasma reactor. As a result, a thin stainless wire, used as the third electrode, has a strong effect to influence the corona discharge of the slit and corona wire, especially to the negative corona discharge. Higher amounts of the output ozone and ozone yield, about 1.27 and 1.29 times for the negative corona discharge, can be obtained with the third electrode, which reveals the effectiveness of the third electrode.

침 전극 기울기에 따른 XLPE의 부분 방전 특성

신종열,안병철,홍진웅,Shin, Jong-Yeol,Ahn, Byung-Chul,Hong, Jin-Woong 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.1

The needle electrode is inserted into the cross-linked polyethylene(XLPE) which is the ultra high voltage cable for electric power. By changing the tilt of the needle electrode, we investigated how the void and the thickness of the insulating layer influence the partial discharge(PD) characteristics and the insulating breakdown. In order to investigate the PD characteristics, The XLPE cable was used to the specimens and the tungsten electrode was used with the needle electrode. And the inner semi-conductive layer material of XLPE cable was used with the negative electrode by bonding with the use of conduction tape. The size of the specimens was manufactured to be $16{\times}40{\times}30[mm^3]$. We confirmed the effect on changing the PD characteristics according to the changing voltage and the tilt of the electrode after applying the voltage on the electrode from 1[kV] to 40[kV] at room temperature. In the PD characteristics, it was confirmed that the PD current of air void specimens with tilt was unstable more than that of no void specimens with tilt. It was also confirmed that the breakdown voltage was decreased because the effect of air void is more active than the change of the needle electrode tilt in the specimen with air void inside the insulation.

플라즈마 디스플레이 패널에서 공통전극에서의 벽전하를 이용한 기입방전특성의 향상

조병권,Cho, Byung-Gwon 대한전자공학회 2013 전자공학회논문지 Vol.49 No.11

플라즈마 디스플레이 패널에서 기입기간 동안 공통전극에서의 벽전하를 이용하여 기입방전특성을 향상시키기 위하여 수정된 구동 파형을 제시한다. 플라즈마 디스플레이의 구동방식에 있어서 초기화 기간 후에 상판의 두 전극에는 음전하가 쌓이게 되고 하판의 기입전극에는 양전하가 쌓이게 된다. 기입기간 중의 기입방전은 주사펄스와 기입펄스가 동시에 인가될 때 발생되는데 주사전극의 음전하와 기입전극의 양전하가 주로 이용된다. 반면에 공통 전극에서는 기입기간 동안 파형인가 없이 전압만 유지하기 때문에 공통전극의 벽전하는 크게 기여하지 않는다. 본 연구에서는 기입기간 중 주사 및 기입 펄스의 인가시각에 맞춰 공통 전극에서도 펄스를 인가하여 기입방전 특성을 조사하였다. 공통 전극에서의 인가전압의 높이와 펄스의 인가시각에 따른 기입 방전특성을 조사하는 실험을 각각 진행하였으며 그 결과 최적의 전압높이와 인가시각 조건하에서 기입방전의 발생시간을 종래보다 약 200 ns 정도 단축시켰다. A modified driving waveform is proposed to improve the address discharge characteristics using wall charge on the common electrodes in plasma display panel. In the driving scheme of plasma display, after a reset period, the negative charge are accumulated on two front electrodes and positive wall charge are accumulated on the address electrode. As the address discharge during an address period is produced when the scan and address pulses are applied at the same time, negative charge on the scan electrodes and positive charge on the address electrodes are mainly used. On the other hand, as the voltage are only maintained without applying the waveform during an address period on the common electrodes, the wall charge is not used on the common electrodes. In this paper, the address discharge characteristics are investigated with changing pulse applying time and applied voltage amplitude on the common electrodes and consequently the producing time of an address discharge are shortened about 200 ns compared with the conventional driving waveform.

Driving Characteristics of a High-Efficacy AC PDP With an Auxiliary Electrode

Choi, Kyung Cheol,Jang, Cheol,Yun, Jin Bhum IEEE 2008 IEEE transactions on electron devices Vol.55 No.6

<P> A new driving waveform was proposed in order to stabilize the driving characteristics of a high-efficacy ac plasma-display panel (PDP) with a coplanar gap of 200 <TEX>$\mu\hbox{m}$</TEX> and an auxiliary electrode. To stabilize the reset and address discharge, an erase pulse was applied to the auxiliary electrode instead of the sustain electrode after the sustain period. The write pulse was applied to the scan electrode, and a reset discharge was induced between the scan and auxiliary electrodes. As a result, the minimum address voltage could be reduced to a level similar to that achieved with a conventional ac PDP with a coplanar gap of 80 <TEX>$\mu\hbox{m}$</TEX>. Furthermore, the address-discharge time lag of the ac PDP with a coplanar gap of 200 <TEX><TEX>$\mu\hbox{m}$</TEX> </TEX> was improved to a level that is comparable with that of the ac PDP with a coplanar gap of 80 <TEX>$\mu\hbox{m}$</TEX>. </P>