• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1157-1158
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• 2015

This work is to study the effect of load current on 6.6 kV power cables in operation. In order to figure out the relationship between load current and temperature of the power cables, we have developed measuring equipment for insulation resistance, temperature, and current tested on 9 cables at power station, Western Power Co. Ltd. The cables used in our test were in operation for the last 18 years. Our research over a year showed that the remaining lifetime of 8 cables was more than 20 years. The remaining lifetime of one cable was about 16 to 18 years.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.276-280
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• 1998

This paper proposes a harmonic a harmonic reduction technique of the parallel-connected twelve-pulse thyristor rectifiers. The proposed system is an improvement over the diode rectifier system with an active interphase reactor [2]. In this scheme, a low KVA (0.15 Po (PU) ) active current source injects a triangular current into an interphase reactor of a twelve-pulse thyristor rectifier along the phase delay angle. The current injection results in near sinusoidal input current with less than 1% THD. Detailed analysis of the proposed scheme along scheme along with design equations is illustrated. Simulation results verify the concept.

• 대한전기학회논문지
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• 제36권4호
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• pp.259-266
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• 1987

In order to drive motor control system precisely, the motor is to be controlled by mmfs and current with sinusoidal waveforms. In this paper the Delta Modulation (DM) Technique is used for generating PWM pulse with sinusoidal waveform. However the motor currents yet contain odd harmonics due to leakage inductances, speed and exitation. To reduce harmonics, the parameter adaptive control method is introduced. That is, Req.C parameter of Delta Modulator is controlled adaptively by parameter adaptor. The adaptive signal is achieved by the difference between motor current and reference waveform, and this signal is converted to the voltage commend signal by adaptive mechanism. The test reslts show that this system is operated smoothly over a wide range of motor speed and motor current is controlled to be sinusoidal waveform adaptively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.563-566
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• 1988

A current-controlled CMOS operational transconductance amplifier(OTA), whose transconductance is directly proportional to the DC bias current, has been developed for many electronic circuit applications. It features that its transconductance is insensitive to temperature unlike that of the bipolar OTA. This property makes it possible to use the proposed OTA as a basic buliding block in electrically variable circuit design. The SPICE simulation shows that the conversion sensitivity of the circuit is 44.62 mv /${\mu}A$ and the linearity error less than 0.54 % over a bias current range from 2 ${\mu}A$ to 120 ${\mu}A$ when the output is loaded with a 1${\Omega}$ resistor.

• 조명전기설비학회논문지
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• 제24권9호
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• pp.26-35
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• 2010

The maximum output torque developed by the machine is dependent on the allowable current rating and maximum voltage that the inverter can supply to the machine. Therefore, to use the inverter capacity fully, it is desirable to use the control scheme considering the voltage and current limit condition, which can yield the maximum torque per ampere over the entire speed range. This controller is controlled speed and current using hybrid PI(HBPI) controller and estimation of speed using ANN. Also, this paper is proposed maximum torque control of induction motor using slip angular speed and current condition at widely speed range. The performance of the proposed induction motor drive with maximum torque control using HBPI controller is verified by analysis results at dynamic operation conditions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.71-74
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• 1998

In this Paper, we investigate the electrical properties of ultra-thin(70${\AA}$) nitrided(NO) and reoxidized nitrided oxide(ONO) film that ale considered to be premising candidates for replacing conventional silicon dioxide film in ULSI level integration. we studied I$\sub$g/-V$\sub$g/ characteristics to know the effect of nitridation and reoxidation on the current conduction, leakage current time-dependent dielectric breakdown(TDDB) to evaluate charge-to-breakdown(Q$\sub$bd/), and the effect of stress temperature(25, 50, 75, 100$^{\circ}C$) and compared to those with thermal gate oxide(SiO$_2$) of identical thickness. From the measurement results, we find that reoxidized nitrided oxide(ONO) film shows superior dielectric characteristics, leakage current, and breakdown-to-charge(Qbd) performance over the NO film, while maintaining a similar electric field dependence compared to NO layer. Besides, ONO film has strong resistance against variation in temperature.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.121-122
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• 2014

This study contemplated the descending air current from the smoke layers related to the smoke logging phenomenon in the sprinkler applied design for effective evacuation safety design. As a result, database on the average particle diameter, particle velocity and distribution of sprinkling was obtained and the relationship between the water amount and particle diameter was obtained. Also, in relation to descending air current, the movement of smoke layer to the bottom at the descending air current velocity of 0.6m/s was observed and stable descending air current was observed in existence of fire source over 100kW in size.

• 대한기계학회논문집B
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• 제33권8호
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• pp.565-572
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• 2009

In this research, a heater using eddy current for generator is designed and some analysis is performed to validate the system. FEM (finite element method) is used for analysing eddy current phenomena at the various speed of rotor with permanent magnet. A real heater system is fabricated. Some experiment is also performed to validate the analysis result. Through the experiment, the FE analysis is validated and we found that the efficiency of developed heater is over 94%.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.433-434
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• 2007

This paper describes a low-voltage dynamic random-access memory (DRAM) focusing on subthreshold leakage reduction during self-refresh (sleep) mode. By sharing a power switch, multiple iterative circuits such as row and column decoders have a significantly reduced subthreshold leakage current. To reduce the leakage current of complex logic gates, dual channel length scheme and input vector control method are used. Because all node voltages during the standby mode are deterministic, zigzag super-cutoff CMOS is used, allowing to Preserve internal data. MTCMOS technique Is also used in the circuits having no need to preserve internal data. Sub-1.2-V 1-Gb mobile DDR DRAM employing all these low-power techniques was designed in a 60 nm CMOS technology and achieved over 77% reduction of overall leakage current during the self-refresh mode.

• 한국전자통신학회논문지
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• 제8권10호
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• pp.1515-1521
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• 2013

본 논문에서는 저항성 누설전류, 과전류, 대기전력 차단기능을 갖는 지능형 콘센트와 연동하는 안드로이드 운영체제의 전력관리 어플리케이션을 개발한다. 개발된 전력관리 어플리케이션을 이용하면 언제, 어디서나 콘센트에서 발생될 수 있는 누전으로 인한 전기화재 및 감전 등을 모니터링하고, 콘센트에 공급되는 전력을 제어하여 실내의 가전기기에 대한 ON/OFF 제어 및 낭비되고 있는 대기전력을 손쉽게 차단할 수 있도록 하였다.