• Journal of the Korean Institute of Telematics and Electronics
• /
• v.25 no.1
• /
• pp.101-107
• /
• 1988

This paper proposes a circuit extractor which extracts a netlist from the CIF input file cntaining the layout mask artwork informations. The circuit extractor extracts transistors and their interconnections, and calculates circuit parameter such as parasitic resistance and parasitic capacitance from the mask informations. When calculating the parasitic resistance, we consider the current flow path to reduce the errors caused by the resistance approximation. Similarly, we consider the coupling capacitance which has an effect on the circuit characteristics, when the parasitic capacitances are calculated. Therefore, using these parameter values as an input to circuit simulation, the circuit characteristics such as delay time can be estimated accurately. The presented circuit extraction algorithm uses a multiple storage quad tree as a data sturucture for storing and searching the 2-dimensional geometric data of mask artwork. Also, the proposed algorithm is technologically independent to work across a wide range of MOS technologies without any change in the algorihm.

• Journal of the Institute of Electronics Engineers of Korea TE
• /
• v.42 no.3
• /
• pp.7-12
• /
• 2005

In this paper, we used class D amplification circuit to improve the decline of error rate caused by low impedance in the Power Line Communication. We manufactured voltage drive circuit and current drive circuit that are driven circuit of power line modem on the present and made a comparison experiment with drivel circuit that uses class D amplifier proposed in this paper. As a result of Experiment, We showed that it has great superiority over other existing drive circuits at rapid impedance change in power line channel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.30 no.1
• /
• pp.37-41
• /
• 2017

In this paper, the fault current limiting characteristics of the flux-lock type SFCL (superconducting fault current limiter) using magnetic application circuit were analyzed. The flux-lock type SFCL has the structure to install the magnetic application circuit, which can increase the resistance of HTSC ($high-T_C$ superconducting element comprising) the SFCL. To analyze the fault current limiting effect of the flux-lock type SFCL through the magnetic flux application circuit, the flux-lock type SFCL either with the magnetic flux circuit or without the magnetic flux circuit was constructed and the fault current limiting characteristics of the SFCL were compared each other through the short-circuit tests.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.63 no.1
• /
• pp.12-18
• /
• 2014

This paper analyzes how to calculate the three phase short circuit current calculation procedures used in the IEC 60909 short circuit. It presented the new procedure of the fault current for the interrupting capacity of the circuit breaker. This procedure is applied to the future power system and calculates the fault current. Power demands are increased because of the growth of the economy for this reason, the fault current of the power system is largely increased and the fault current procedure for the proper interrupting capacity calculation of the existing or the new circuit breaker is essential. How to calculate the three phase short circuit current for ac electrical system and select the high voltage and low voltage circuit breaker based on IEC 60909 standards.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.735-736
• /
• 2008

There are many equipments for the Short Circuit Test, for example Short Circuit Generator, Induction Motor, Sequence Timer, CLR, Back Up Breaker, Making Switch and Excitation Equipment etc. Gradually an allowable tolerance of the short circuit test voltage is become smaller by the standards for short circuit test. The excitation equipment of short circuit generator is very important for test voltage is adjusted by the excitation equipment. Especially the excitation equipment must be possessed character of exactitude, durability and inalterability because some times around 10,000 times opening and closing short circuit test is requested by clint, which must be done within one minute. The purpose of this study for function and operation of the excitation equipment which rated DC voltage is 1,000V, rated DC current is 300A, rated out put is 30kW and type is YNEX 97S-441/609, is to help operation of short circuit generator.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.25 no.9
• /
• pp.1201-1208
• /
• 2001

Variable temperature anemometer(VTA) has greater sensitivity than a conventional constant temperature anemometer(CTA). In order to design a reliable VTA system, however, an elaborate photoconductive cell stabilizing circuit which plays a key role in setting wire-overheat ratio should be firstly developed. In this study, a stabilizing circuit which adopts proportional-integral analog controller was proposed and thoroughly tested for its accuracy and reproducibility. In contrast to the available circuit suggested by Takagi, the present circuit has characteristic that the resistance of a photoconductive cell increases with the increase of input voltage, which makes the current circuit very suitable for the design of VTA. Finally, VTA adopting stabilizing circuit was made and the enhanced sensitivity of the VTA was validated experimentally by comparing the calibration curves of VTA and CTA.

• Journal of Power Electronics
• /
• v.9 no.2
• /
• pp.259-266
• /
• 2009

In order to increase the power density of power converters, reduction of the switching losses at high-frequency switching conditions is one of the most important issues. This paper presents a new gate drive circuit that enables the reduction of switching losses in both the Power MOSFET and the IGBT. A distinctive feature of this method is that both the turn-on loss and the turn-off loss are decreased simultaneously without using a conventional ZVS circuit, such as the quasi-resonant adjunctive circuit. Experimental results of the switching loss of both the Power MOSFET and the IGBT are shown. In addition, an energy recovery circuit suitable for use in IGBTs that can be realized by modifying the proposed gate drive circuit is also proposed. The effectiveness of both the proposed circuits was confirmed experimentally by the buck-chopper circuit.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.513-513
• /
• 2000

An integrable circuit technique for implementing high-speed analog two-input Max/Min circuit is described. The realization method is suitable for fabrication using CMOS technology. The proposed circuit comprises a current mirror and electronic switch connected with a absolute value circuit. The maximum or minimum operation of the proposed circuit can be selected by an external control voltage. The proposed analog Max/Min circuit has a very sharp transfer characteristic and is suitable for real-time systems. Simulation results verified the circuit performances are agreed with the expected values.

• Proceedings of the KIEE Conference
• /
• 1997.07b
• /
• pp.533-535
• /
• 1997

Chua's circuit is a simple electronic network which exhibits a variety of bifurcation and attractors. The circuit consists of two capacitors, an inductor, a linear resistor, and a nonlinear resistor. In this paper we analyze a circuit obtained by replacing the parallel LC resonator in the Chua's circuit by lossless transmission line. By using the method of characteristics of this circuit we show that various periodic motions and chaotic motions can the attained according to parameter variations. From Chua's circuit with a lossless transmission line, a variety of chaotic attractors which are similar to those of the normal Chua's circuit are observed.

• Journal of Power System Engineering
• /
• v.1 no.1
• /
• pp.144-153
• /
• 1997

The magnetic levitation system is utilized in the magnetic bearing of high-speed rotor because of little friction, no lubrication, no noise and so on. The magnetic levitation system need the feedback controller for the stabilization of system, and gap sensors are generally used to measure the gap. The use of gap sensors brings out the increase of the number of troublesome, and the decrease of the control performance because of the dislocation between the measurement point and the control point. This paper presents the design of the gap estimation circuit for the sensorless method proposed by authors in the magnetic levitation system. We made the gap estimation circuit which was composed of both the superposition circuit and the measuring circuit. And we investigated the validity of the usefulness of the proposed sensorless method in the magnetic levitation system through results of actual experiment.