• Journal of the Korea Institute of Military Science and Technology
• /
• v.14 no.6
• /
• pp.1166-1170
• /
• 2011

For developing the ignition device for the interceptor of Korean active protection system, the design parameters of the ignition device which should have a short ignition delay time and sufficient energy for propellant ignition were studied. The electric primer instead of mechanical primer was adopted for deceasing delay time, and ignition code was used for decreasing the time difference of flame propagation from the flame holes. The developed ignition device showed the ignition delay time of a few ms. When the designed ignition device was applied to the open-type propulsion devices, the stable interior ballistic characteristic was showed in a firing test.

• Journal of Satellite, Information and Communications
• /
• v.8 no.1
• /
• pp.45-53
• /
• 2013

An electrostatic discharge (ESD) protection device, so called, N-type extended drain silicon controlled rectifier (NEDSCR) device, was analyzed for high voltage I/O applications. A conventional NEDSCR device shows typical SCR-like characteristics with extremely low snapback holding voltage. This may cause latch-up problem during normal operation. However, a modified NEDSCR device with proper junction/channel engineering using counter pocket source (CPS) ion implantation demonstrates itself with both the excellent ESD protection performance and the high latch-up immunity. Since the CPS implant technique does not change avalanche breakdown voltage, this methodology does not reduce available operation voltage and is applicable regardless of the operation voltage.

• Proceedings of the KIEE Conference
• /
• 2005.05a
• /
• pp.90-92
• /
• 2005

In this paper, we design a digital protection IED(Intelligent Electric Device) for a distributed power system in connection with power grid. The device can measure various elements for protection and communicate with another devices through network. The protection IED is composed of specific function modules: signal process module which converts analog signal from PT and CT handle algorithm to digital one; communication module for connection with another IEDs; input/output module for user-interfaces; main control module for control the whole modules. A general purpose DSP board with TMS320C2812 is used in the IED. Experiments with the power system simulator DOBLE have been made to verily the proposed hardware system.

• Journal of Advanced Marine Engineering and Technology
• /
• v.23 no.2
• /
• pp.159-167
• /
• 1999

This paper presents a new transient voltage blocking device(TOBD)which low power and high frequency bandwidth to protect info-communication facilities from transient voltages. Conventional protection devices have some problems such as low frequency bandwidth low ener-gy capacity and high remnant voltage. in order to improve these limitations a hybrid type TOBD which consists of a gas tube avalanche diodes and junction type field effect transistor (JFETs) is developed. The TOBD differs from the conventional protection devices in configuration and JFETs are used as an active non-linear element and a high speed switching diode with low capacitance limited high current. Therefore the avalanche diode with low energy capacity are protected from the high current and the TOBD has a very small input capacitance. From the performance test using combination surge generator which can produce $1.2/50{\mu}m$ 4.2 kV/max, $8/20{\mu}m$ 2.1 kAmax it is confirmed that the proposed TOBD has an excellent protection per-formance in tight clamping voltage and limiting current characteristics.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.10
• /
• pp.102-108
• /
• 2011

The existing power flow has a single direction to the line end but the bidirectional power flow will possibly occur depending on the output capacity in the 22.9[kV] distribution power system connected with the dispersed generation(DG). So these characteristics would influence the power system management. The DG have many advantages such as assistance source, Load share etc. So the utility must apply the bidirectional protection system so as to maximize an advantage of DG. This paper describes the field test case of bidirectional protective device in order to investigate the device performance when applied to bidirectional power system. We have tested in the power system test site of KEPCO and these tests provide the basis for performance verification test of bidirectional protective device in the power system.

• Proceedings of the KIEE Conference
• /
• 2002.11b
• /
• pp.53-58
• /
• 2002

Sheath circulating current is increased as the change of sheath mutual impedance which is caused by imbalance of cable system, and different section length between joint box. If excessive current flows in sheath. sheath loss will be increased and then transmission capacity of underground transmission system is reduced. Accordingly, This paper proposed sheath current reduction device using resistor and reactor and proved the reduction effect of that device using EMTP/ATP. And also in this paper, when transients are occurred at the underground system with reduction device by ground fault and lightning surge. we analyzes transient effect of system variously. From this result. authors establish the protection methods of sheath circulating current reduction device.

• Journal of IKEEE
• /
• v.11 no.1 s.20
• /
• pp.54-60
• /
• 2007

In this study novel ESD protection device, namely, N/P-type Low Voltage Triggered SCR, has been proposed, for high speed I/O interface. Proposed device could lower high trigger voltage($\sim$20V) of conventional SCR and reduce latch-up phenomenon of protection device during the normal condition. In this Study, the proposed NPLVTSCR has been simulated using TMA MEDICI device simulator for electrical characteristic. Also the proposed device's test pattern was fabricated using 90nm TSMC's CMOS process and was measured electrical characteristic and robustness. In the result, NPLVTSCR has 3.2V $\sim$ 7.5V trigger voltage and 2.3V $\sim$ 3.2V holding voltage by changing PMOS gate length and it has about 2kV, 7.5A HBM ESD robustness(IEC61000-4-2).

• Journal of Satellite, Information and Communications
• /
• v.7 no.2
• /
• pp.18-24
• /
• 2012

High current behaviors of the extended drain n-type metal-oxide-semiconductor field effects transistor (EDNMOSFET) for electrostatic discharge (ESD) protection of high voltage operating LDI (LCD Driver IC) chip are analyzed. Both the transmission line pulse (TLP) data and the thermal incorporated 2-dimensional simulation analysis demonstrate a characteristic double snapback phenomenon after triggering of biploar junction transistor (BJT) operation. Also, background doping concentration (BDC) is proven to be a critical factor to affect the high current behavior of the EDNMOS devices. The EDNMOS device with low BDC suffers from strong snapback in the high current region, which results in poor ESD protection performance and high latchup risk. However, the strong snapback can be avoided in the EDNMOS device with high BDC. This implies that both the good ESD protection performance and the latchup immunity can be realized in terms of the EDNMOS by properly controlling its BDC.

• Proceedings of the KIPE Conference
• /
• 2012.07a
• /
• pp.621-622
• /
• 2012

The thermal over-current relay or electronic motor protection relay is mostly used as the open-phase detection device of the three-phase motor or load. When the over-current or overheat of electric line is generated, it detects and operates circuit breaker, but there is the defect that the sensing speed is slow, the operation can be sometimes failed, and the precision is decreased. In order to improve these problems, this paper is proposed a new control circuit topology for open-phase protection using semiconductor devices. Therefore, the proposed open-phase protection device enhances the sensing speed and precision, and has the advantage of simple fitting in the three-phase motor control panel in the field, as it manufactures into small size and light weight.

• Journal of IKEEE
• /
• v.26 no.3
• /
• pp.520-523
• /
• 2022

In this paper, an ESD protection device with a simpler structure than the existing ESD protection device is proposed. The proposed new structure operates an additional NPN parasitic bipolar transistor by adding an N+ diffusion region and connecting it to the bridge region, thereby lowering the current gain. As a result, it was confirmed that the proposed ESD protection device has a trigger voltage of 10.8V and a holding voltage of 6.1V. It is expected to have reliability for 5V applications and is expected to have high tolerance characteristics.