• Proceedings of the KIEE Conference
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• summer
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• pp.554-556
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• 2004

Testing capacity of KERI synthetic short-circuit testing facilities has been upgraded to fulfill the requirements up to 550kV 63kA, 1-break circuit breaker ratings. Specially the current capacity was increased 50kA to 63kA and the full type test of 362kV 63kA circuit breaker(1-break) was firstly completed in domestic. UP to now, domestic manufacturers have depended on the foreign testing laboratory for performance verification of newly designed products. This paper introduces the summary of the increased short-circuit testing facilities, the testing techniques and its results for the making and breaking performance of 362kV, 63kA circuit breaker which was Performed according to IEEE C37.06(1999) used in North America.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.800-804
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• 2005

Load flow and short circuit fault transients of a power distribution system with wind turbines as dispersed generation units is presented. Usage of renewable energies such as wind is already a small part of total installed power system in medium and low voltage networks. In this paper, a radial power distribution system with wind turbines is simulated using DIgSILENT PowerFactory software for their influence on load flow and short circuit fault transients. Short fault occurring in dispersed generation systems causes some problems for the system and costumers such as fault level increase or the problems of sudden fluctuations in the current, voltage, power and torque of the double fed induction machine utilized in the wind turbines which have been studied and investigated.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2100-2101
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• 2008

This paper is studied on a protective control system for electrical fire and electrical faults due to over current or electric short circuit faults by using electrical thermal characteristics of PTC (Positive Temperature Coefficient) thermistor and current response characteristics of high sensitive reed switch. The PTC thermistor has characteristic of positive resistivity temperature coefficient according to the temperature variation, which is construction of a regular square and cube demarcation with BaTiO3_Ceramics of positive temperature coefficient. Also PTC thermistor shows the phenomenon which is rapidly increased in the resistivity if the temperature is increased over Curie temperature point, and reed switch, which is used for electrical fault current sensing devices, have a excellent characteristic of response velocity in degree of ${\mu}s{\sim}ms$ that sensing magnetic flux in proportion to dimension of line current. This paper is proposed on a protective control system use PTC thermistor and reed switch for sensor which is protected from electrical fire due to overload faults or electric short circuit faults. Some experimental results of the proposed electric safety control device are confirmed to the validity of the analytical results.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.3
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• pp.365-373
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• 2015

We propose a simple and compact thyristor-based neuron circuit. The thyristor exhibits bi-stable characteristics that can mimic the action potential of the biological neuron, when it is switched between its OFF-state and ON-state with the help of assist circuit. In addition, a method of inter-neuron connection with synaptic devices is proposed, using double current mirror circuit. The circuit utilizes both short-term and long-term plasticity of the synaptic devices by flowing current through them and transferring it to the post-synaptic neuron. The double current mirror circuit is capable of shielding the pre-synaptic neuron from the post synaptic-neuron while transferring the signal through it, maintaining the synaptic conductance unaffected by the change in the input voltage of the post-synaptic neuron.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.37-38
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• 2010

For MHz-class high frequency inverter in wireless power transfer applications, the voltage/current surges can be occurred in power stage when driving on the inverter. And also, the high-frequency oscillations can be produced at a high switching frequency due to the parasitic elements. The voltage and current stresses of the switching devices lead to the switching losses. The efficiency of the high frequency inverter will be reduced. And the inverter circuit with the sudden voltage and current fluctuations also generates the noise such as the EMI. Zero voltage, zero current switching technique can be used to reduce the switching loss and the noise. The high power density and high efficiency can be obtained. In this paper, the high-frequency inverter for short-range wireless power transfer applications was discussed. The feasible inverter circuit is analyzed in the circuit operating characteristics and the results are verified by the simulation.

• Proceedings of the KIEE Conference
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• summer
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• pp.836-838
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• 2004

Alternating current switch-fuse combinations shall be designed so as to protect for load circuit of distribution line. this switch system shall be test on making and breaking at short-circuit current. the test dutys were performed to prove correct coordination between the switch and fuses in applied test conditions This paper describes characteristics and test method for prove to performance of alternating current switch-fuse combinations.

• Proceedings of the KWS Conference
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• 2001.10a
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• pp.33-36
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• 2001

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1350-1352
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• 1995

This paper discribed the characteristic of I-t cross-over-point between current limited-fuse and explusion fuse(Bay-O-Net Fuse) and fuse protection in pad-mounted transformer that was generated internal faults and the short circuit of secondary side(load side). In the I-t cross-over-point, current limited fuse was melted when transient recovery voltage was raised rapidly.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.57-59
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• 2005

This paper describes the applicability of HVDC system to KEPCO system in terms of educing short circuit current. Especially, the effect of reducing the short circuit current n Gyungin area and Seoul area by using HVDC system was mainly investigated. In addition, the transaction of electric power between ar was, security problem, and economic aspects were also examined.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.59-63
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• 2022

In this study, we study of luminescent solar concentrators comprise thick glass with broadband antireflection coating deposited on the top surfaces and inorganic phosphor layers contacted on the bottom surfaces. Solar cells are contacted to the lateral surfaces of the glass. Experimental results show the broadband antireflection coating increased the short-circuit current of the solar cell.