• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.1067-1068
• /
• 2008

An inverter for driving flat fluorescent lamp(FFL) with various protection circuits using micro controller(Micom) is proposed in this paper. The inverter will be shut down if the fault operating conditions such as open lamp, over current and over voltage are detected.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.1853-1859
• /
• 2008

IGBT modules are designed for low loss, rugged for all environments and user friendly. Low on state saturation voltage with high switching speed is the primary concerns. In this paper selection of IGBT, module ratings and characteristics are discussed. The IGBT design topic of protection against over voltage and over current are covered. Emphasis on turn off switching, short circuit switching and necessary precautions are dealt. Selection of IGBT device, gate drive power, and its lay out considerations are covered in detail.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1975-1980
• /
• 2004

A parallel active power filter is designed and implemented to compensate for undesired current harmonics generated by a nonlinear load. The filter works based on PWM strategy and control signal is generated using a model predictive controller. To evaluate the achievements, a PI controller is also designed and implemented. Experimental results indicate about 50% increase in the efficiency over PI controller.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2002.02a
• /
• pp.330-333
• /
• 2002

This study is concerned with the optimal design of DC reactor type high-Tc superconducting fault current limiter(SFCL) by Newton method. What should be first thought over in developing SFCL is the condition in which the cost function is minimized under given constraints. So, this condition is supposed to be the values corresponding to the variables the cost function counts on. In this paper, we got the result for the SFCL available at the level of 6.6kV-200A by means of simulation.

• Proceedings of the KIPE Conference
• /
• 2001.10a
• /
• pp.7-10
• /
• 2001

This paper provides a solution for the problem of efficiency decrease caused by load variation. A novel control scheme of tracking the PT's operation frequency for the maximum efficiency is proposed. As a result, a high efficiency over $80\%$ has been achieved even under the output-current decrease down to $10\%$ of the full load current.

• Proceedings of the KIPE Conference
• /
• 2000.07a
• /
• pp.294-298
• /
• 2000

A new pulse multiplication technique based on 6-pulse thyristor converters is proposed in this paper. With the proposed technique 12-pulse 18-pulse and 24-pulse operations have been obtained both on the input current and on the output voltage. A control strategy over the whole range of phase angle is provided along with sophisticated input current and output voltage analysis. Experimental results from a laboratory prototype verify the proposed theory.

• 전기의세계
• /
• v.29 no.11
• /
• pp.733-741
• /
• 1980

A novel six-step current source inverter (CSI) with DC-side commutation and energy rebound capability is presented with detailed explanation of the circuit operation. The prposed inverter can operate in a very wide range of frequency and load variation by employing DC-side commutation. Also, the energy rebound makes the use of low voltage SCR's possible and increases the inverter efficiency. Motor operation is also possible in four quadrants in this proposed current source inverter. The advantages of the proposed CSI over conventional ones are described and experimental results are given in oscillograms.

• Resources Recycling
• /
• v.9 no.1
• /
• pp.3-14
• /
• 2000

In order to prospect current recycling status in Korea, wastes generation and recycling rate were reviewed. Approximately 188,600 ton/day of wastes was generated in 1998; 44,600 ton/day of domestic waste and 144,000 ton/day of industrial waste. During the last five years, waste management laws such as recycling law and environment friendly industry law were prepared. In this article, concerning over waste generation and recycling, the problems and technological developments associated with recycling were summarized.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.32A no.10
• /
• pp.25-34
• /
• 1995

A new vertical power MOSFET with over-current protection capability is proposed. The MOSFET consists of main power MOSFET cell, sensing MOSFET cell and lateral npn bipolar transistor. The proposed MOSFET may be fabricated by a conventional DMOS process without any additional fabrication step. Overcurrent state is sensed by the newly designed lateral bipolar transistor. Mixed-mode simulations proved that the overcurrent protection is achieved by the proposed MOSFET successfully with a small protection area less than 0.2 % of the total die area.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2001.02a
• /
• pp.65-67
• /
• 2001

Temperature and resistance of a Bi-2223 tape for fault currents up to 10 $I_{c}$ were measured in two types of samples taking into account real applications. The results indicate that the Bi-2223 tape is safe from burn-out for fault currents with a few cycles up to 10 I$_{c}$. For fault currents of over an order of magnitude higher than the nominal current, the temperature of the Bi-2223 tape depends strongly on fault durations.s.