• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.11
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• pp.3676-3685
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• 1996

Enhancement of the ignitability was necessary to realize the lean burn engine. The characteristics of multiple-spark capacitor discharge igniter(MSCDI) usefulness of which for lean burn was examined in constant volume combustion chamber and evaluated in spark ignition engine. Noise of MSCDI for engine was restricted by adoption of low voltage control system. It was found that the adaptability for high engine speed was remarkable. Lean limit in engine with MSCDI was extended 10% than conventional coil ignition system. Also maximum brake thermal efficiency was almost enhanced 1%.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.6
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• pp.11-18
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• 2018

A pulse detonation engine (PDE) requires high operating frequency greater than 100 Hz to get meaning thrust as a propulsion devise. Thus a PDE needs an ignition circuit operating precisely at high operating frequencies. In this paper AC(alternating current) and DC(direct current) types of ignition circuits were designed and compared. Each circuit was tested at operating frequencies from 16.66 to 100.00 Hz by measuring the input signal of each circuit and the voltage change in the primary coil of the transformer. Results show that the DC power circuit can attain a maximum error rate of 5.15% at higher operating frequencies, whereas the AC power circuit displays a negligible agreement with the operating signal at frequencies greater than 33.33 Hz. Therefore it is confirmed that DC-powered ignition circuit is preferable for the PDE operating at high frequencies.

• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.156-157
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• 2012

본 논문은 불꽃 점화 방식 엔진에서 차량의 주행상태에 따른 점화코일의 전류량을 측정하여 추가적인 전류를 공급하는 충전 전류제어 장치를 고안하였다. 점화 코일의 전류를 안정적으로 공급하고 과전류를 방지함으로써 차량 엔진의 출력 향상 및 효율적인 연소가 가능하도록 하였으며, 다이나모 장비를 이용하여 출력과 토크에 대한 성능평가를 하였다. 실험결과는 제안하는 장치의 유효성을 보여주었다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.11a
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• pp.173-177
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• 1998

In this paper, we reported an outbreak of fire hazard of ballast for fluorescent lamp. The surface structure and composition of ballast coil analyzed by using metallurgical microscope, scanning electron microscope(SEM) and energy dispersive x-ray spectroscopy(EDX). The surface of molten mark appeared columnar structure and void. EDX analysis indicated that the molten mark spectra were composed not only of the corresponding original spectra but also of several new lines.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.3
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• pp.106-112
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• 2012

Since air pollution problem by emissions from automotive vehicles has become social issues, lean-burn gasoline direct injection (GDI) engine is focused as an alternative to meet the requirement of reinforced emission regulation and improved fuel consumption. Spray-guided type DI combustion is promising technology, which characterized by the centrally mounted injector and closely positioned spark plug, since stable lean combustion can be realized even at ultra-lean mixture condition. In the present study, the effect of multi-ignition with developed charge coil on combustion and emission characteristics was investigated in optical accessible single cylinder engine. In order to fully understand the in-cylinder phenomena and the mechanisms of emission production, optical diagnostics, such as flame visualization was also carried out at frequently using operating condition. Multi-ignition is effective to improve fuel economy but increase NOx emission at flammability limit.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.5
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• pp.15-21
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• 1980

An engine control system in which the conventional mechanical ignition system is studied. The contact point of the breaker is replaced by the contactless magnetic pick up sensor from which the information of the speed and the position of the crankshaft is extracted , and further an electronic High Energy Ignitim System Is designed, implemented and tested . The High Energy Igniticwl System increases the secondary spark voltage of the ignition coil from the conventional 10000~15000 volts to the 30000~40000 volts resulting in improving the combustion efficiency. Also, instead of the conventional advimce mechanism forigniliontiming control, a microprocessorbased timinng mechanisn is installed to determine the ignition timing data in response to the engine rpm and the intake manifold vacuum.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.70-75
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• 2014

The experiment was done on traveling at the speed of 20km/h, 60km/h and 100km/h using the performance testing mode for chassis dynamometer. The experimental method were employed to measure the waveform of secondary ignition coil and exhaust emission. In this experiment, the correlation between the secondary waveform coming from ignition coil and exhaust emission were measured in decrepit vehicle. The secondary waveform characterized by the value of effective discharge energy. The following results are obtained by analyzing the data relativity between the effective discharge energy and exhaust emission. The variation rate of effective discharge energy was largest 60km/h, 20km/h, 100km/h velocity in the ordered named. As the vehicle velocity increases, the average variation rate of CO and $NO_X$ decreases and that of HC and $CO_2$ decrease. The value of effective discharge energy, CO, $NO_X$ and fuel consumption is measured badly in case of car with failures in MAP, spark plug and good in case of car with before and after maintenance regardless of vehicle velocities. The value of effective discharge energy is to be nearly parabolic shape as vehicle velocity increases. As the value of effective discharge energy increases, the value of $NO_X$, HC and $CO_2$ decrease, the value of CO increase. The most sensible factors of exhaust emission were CO, $NO_X$, and the small variation factors were HC, $CO_2$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.253-256
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• 1997

Recently, mixture insulating oils is widely used in respect that the physical and the electrical properties is more excellentthan mineral oils, such as alkylbenzene oils and silicone oils, and that cost is lower than alkylbenzene oils or silicone oils. Also, it is important to research for the additive BTA(Benzotriazole) as a study for the phenomena of streaming electrification of mineral oils. So, mixture insulating oils class 7-2, is selected as a specimen in this experiments, and the contents of BTA in specimen are 0.2[ppm], 10[ppm] and 30[ppm], respectively. Then, the physical and the electrical properties for each specimen is made researches.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1414-1416
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• 1997

The electrical breakdown characteristics of the synthetic fluids No.2 of KS class VII used for insulating and cooling the materials for the ignition coil are studied. Also, Benzotriazole(BTA) as the streaming electrification suppressant additive is added to the oil, and the change of electrical properties due to different BTA concentration is investigated. To investigate the electrical characteristics, the breakdown strength of each specimen by an experiment for AC breakdown are analyzed. The breakdown strength of specimen by adding BTA is higher than virgin specimen in low e region, but lower than that in high region because of melting BTA. It is considered that the effective content of BTA as charge suppressant additive is about 10[ppm] from the results of AC breakdown.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2043-2045
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• 2005

현재 점화코일은 소형화 및 친환경성을 위해 에폭시 몰딩 절연층으로 변화되었다. 그러나 에폭시 몰딩으로 변환됨에 따라 점화코일 내부 절연층에 대한 절연진단 및 노화에 대한 정확한 진단의 어려움으로 적절한 교체시기를 예측하기 더욱 어려워졌다. 그로 인해 점화장치부분에 대한 예기치 못한 사고는 대형사고 유발을 초래할 수 있다. 이에 본 논문에서는 비파괴검사의 일종인 부분방전을 이용한 열화검출을 연구하기 위해 열화에 따른 위상각-방전전하량-방전빈도수의 분포 특성을 조사하였다. 또한 방전 발생의 분포가 동일 조건에서도 매우 불규칙성을 가지고 있으므로 데이터의 정량화를 위해 불규칙적인 통계처리를 위한 와이블 분포를 사용하여 기기의 고장시간예측을 조사하였다.