• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.2030-2031
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• 2007

This paper is purpose to understand the surge property for the shorted turn or shorted strand in high voltage motor stator windings. a shorted turn in high voltage motor windings causes a huge circulating current. and overheat windings, consequently burns the motor. a few shorted strands not cause winding failure immediately, but they increase the winding loss and temperature increase due to contact resistance. We carried out the surge test for three cases, normal winding, shorted turn winding and shorted strand winding. and we analyzed the test result.

• Journal of Magnetics
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• v.17 no.1
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• pp.56-60
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• 2012

This paper presents an analysis and experiment of the flat coil actuator with shorted turn. The flat coil actuator is widely used in high precision products because it has no friction between the moving coil and the guide. A shorted turn and a center pole are placed into the flat coil actuator in order to reduce the inductance of the coil and improve the initial response when the actuator is voltage-driven. Enhanced dynamic performance of the flat coil actuator with shorted turn was demonstrated by simulation and experiment.

• Journal of Magnetics
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• v.18 no.4
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• pp.466-472
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• 2013

This paper presents a new design of the hybrid magnet engine valve actuator using the shorted turn for enhanced dynamic performance. The quick response of coil electric current is the most important factor that determines the opening and closing performance of the hybrid magnet engine valve. The conventional hybrid magnet engine valve actuator, however, has a delayed initial electric current rising when it is driven by voltage control because of the coil inductance which is a typical characteristic of an electromagnetic coil. A shorted turn is newly placed into the upper yoke of the hybrid magnet engine valve actuator to reduce coil inductance and thus, to hasten the initial electric current rising. We performed a dynamic finite element analysis to demonstrate the improvement of the dynamic characteristics of the hybrid magnet engine valve actuator due to the shorted turn.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.11
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• pp.742-747
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• 1999

On-line diagnosis system has been developed and is now applied the detection of shorted turns in the field winding of large generator. This system consists of data aquisition system and display PC. The data aquisition system detects voltage waveforms from flux probe sensor installed in the stator slot. The display PC shows theshorted-turn situation of generator rotor winding. A shorted-turn diagnosis test wasperformed on five gas turbine generators at the Seoinchon combined cycle power plant. The test was conducted using an new diagnosis system and digital oscilloscope which can identify the pole location, the slot number and the number of shorted turns within each slot. It is confirmed that results of two systems are very same in the field tests.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.4
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• pp.562-567
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• 1996

A new lateral MOS controlled thyristor, named Shorted Anode LMCT(SA-LMCT), is proposed and analyzed by a two-dimensional device simulation. The device structure employs the implanted n+ layer which shorts the p+ anode together by a common metal electrode and provides a electron conduction path during turn-off period. The turn-off is achieved by not only diverting the hole current through the p+ cathode short but also providing the electron conduction path from the n-base into the n+ anode electrode. In addition, the modified shorted anode LMCT, which has an n+ short junction located inside the p+ anode junction, is also presented. It is shown that the modified SA-LMCT enjoys the advantage of no snap-back behavior in the forward characteristics with little sacrificing of the forward voltage drop. The simulation result shows that the turn-off times of SA-LMCT can be reduced by one-forth and the maximum controllable current density may be increased by 45 times at the expense of 0.34 V forward voltage drop as compared with conventional LMCT. (author). 11 refs., 6 figs., 1 tab.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.137-140
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• 2003

Shorted-turns can have significant effects on a generator and its performance. Shorted-turn sensor for synchronous generator's field winding have been developed. One of effective method detecting inter-turn short circuits on round rotor winding is a method using sensor detecting. But the method needs duplicate design of sensor for characteristic change according to types and forms of generator Thus sensing skill without sensor depend on change of electric property in generator. For the reason, this paper presents shorted-turns phenomenon and the characteristic analysis of shorted-turns In synchronous generator by using 2-D finite element method(FEM).

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.195-197
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• 2001

The shorted-turn sensor for generator's field winding has been developed. The sensor, installed in the generator air-gap, senses the slot leakage flux of field winding and produces a voltage waveform proportional to the rate of change of the flux. For identification of reliability for sensor, a shorted-turn test was performed at the Seoinchon & Sininchon combined cycle power plant on gas turbine generator. This sensor will be used as a detecting of shorted-turn for generator's field winding.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.3
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• pp.168-174
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• 2004

On-line monitoring system(OMS) has been developed for the pumped storage generator/motor The OMS is applied to diagnosis of the PD(partial discharge) activity of stator insulation, the shorted-turn of rotor winding and the variation of the air-gap between stator and rotor. The OMS consists of DAS(data acquisition system), main server system, gateway and display PC. The DAS measures the PD, the shorted-turn and air-gap from three sensors installed on the generator/motor. The gateway controls the data which sent by DAS. The main server system saves the data, analyzes the data and conducts the diagnostic algorithm. The display PC shows the diagnostic results of partial discharge, shorted-turn and air-gap. Field tests were conducted using PDA(partial discharge analyzer). The results of the OMS and PDA measurements can be directly correlated with normalized quantity number(NQN), PD magnitude(Qm) and PD pattern.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1765-1767
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• 2001

The shorted-turn sensor for generator's field winding has been developed. The sensor, installed in the generator air-gap, senses the slot leakage flux of field winding and produces a voltage waveform proportional to the rate of change of the flux. For identification of reliability for sensor, a shorted-turn test was performed at the Seoinchon combined cycle power plant on gas turbine generator. This sensor will be used as a detecting of shorted-turn for generator's field winding.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2114-2116
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• 1999

The shorted-turn sensor for synchronous generator's field winding has been developed. The sensor, installed in the generator air-gap, senses the slot leakage flux of field winding and produces a voltage waveform proportional to the rate of change of the flux. For identification of reliability for sensor, a shorted-turn test was performed at the Seoinchon combined cycle power plant on gas turbine generator. This sensor will be used as a detecting of shorted-turn for synchronous generator's field winding.