• New & Renewable Energy
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• v.2 no.3
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• pp.5-9
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• 2006

We have fabricated a micro power generator which changes vibrational energy into useful energy. With vibrating a magnet on the surface of a winding coil, the micro power generator produce alternating voltage. We have changed the vibrational frequency from 0.5Hz to 10Hz. AC voltage of $20{\sim}25mV$ was generated at the frequency of 1Hz. When the vibration was 3Hz, AC voltage of 80mV was obtained. We have rectified and stepped up the input voltage using a quadrupler circuit. The voltage was stepped up to 130mV.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1835-1837
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• 1996

Characteristics of Discharge and nonthermal plasma generation in a micro-air gap spacing between a micro-dielectric barrier and a electrode have been investigated experimentally to chert the potential to be used as a micro-scale nonthermal plasma generator. It is found that the output ozone concentration, as a nonthermal plasma intensity parameter, of the micro-air gnp nonthermal plasma generator depended greatly upon the air gap spacing and thickness of the dielectric barrier. As a result, there is a optimal air gap sparing in the same micro dielectric barrier to generate ozone effectively. And the higher ozone concentration was generated from the thinner micro-barrier.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.1112-1118
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• 2014

In island and backcountry areas, electrical power is usually supplied by diesel generators. It is difficult for small scale diesel generators to have an economy of scale owing to the usage of fossil fuels to produce electricity. Also, there is a problem of carbon dioxide emissions that brings some environmental pollution to the entire region of the area. For solving those, this paper proposes a design method of autonomous micro-grid to minimize the fossil fuels of diesel generator, which is composed of diesel generator, wind turbine, battery energy storage system and photovoltaic generation system. The proposed method was verified through computer simulation and micro-grid operation system.

• The KSFM Journal of Fluid Machinery
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• v.17 no.3
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• pp.19-24
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• 2014

Development of long-term mobile energy sources for mobile robots or small-sized unmanned vehicles are actively increasing. The micro gas turbine generator (MTG) is a good candidate for this purpose because it has both of high energy density and high power density, and 500W class MTG is under development. The designed MTG can be divided into 2 main parts. One part consists of motor/ generator and compressor, and the other one consists of combustor, recuperator and turbine. 500W class MTG is designed to operate at ultra-high speed of 400,000 rpm in high turbine temperature over $700^{\circ}C$ to improve the efficiency. Because the magnetism of NdFeB permanent magnet for the motor/generator could be degraded if the temperature is over $150-200^{\circ}C$, MTG needs the thermal insulation to block the heat transfer from combustor/turbine side to motor/generator side. Moreover, the motor/generator is allocated to get the cooling effect from the rapid air flow by the compressor. This study presents the experimental results to verify whether the thermal insulator and air flow are effective enough to keep the motor/generator part in the low temperature less than $100^{\circ}C$. From the motoring test by using the high temperature test rig, it was confirmed that the motor/generator part could maintain the temperature less than $50^{\circ}C$ under the condition of 1.0 bar compressed air.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.2 s.344
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• pp.1-7
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• 2006

This is a preliminary study on the MEMS(Miro Electro Mechanical System) electrostatic power generator. It suggested a converting device to change from the electrostatic to the dynamic electricity. To testify, it used Silvaco simulation tools(Athena and Atlas) and fabricated the converting device. The result of the simulation and test it seems to convert electrostatic into dynamic electricity effectively.

• The KSFM Journal of Fluid Machinery
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• v.19 no.1
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• pp.24-30
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• 2016

In this study, a 2W micro-gas turbine engine was designed using micro-electro-mechanical systems (MEMS) technology, and experimental investigations of its potential under actual combustion conditions were performed. A micro-gas turbine (MGT) contains a turbo-charger, combustor, and generator. Compressor and turbine blades, and generator coil were manufactured using MEMS technology. The shaft was supported by a precision computer numerical control (CNC) machined static air bearing, and a permanent magnet was attached to the end of the shaft for generation. A heat transfer analysis found that the cooling effect of the air bearing and compressor was sufficient to cover the combustor's high temperature, which was verified in an actual experiment. The generator performance test showed that it can generate 2W at design rotational speed. Prototype micro-gas turbine generated maximum 1 mW electric power and lasted up to 15 minutes.

• Journal of Sensor Science and Technology
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• v.19 no.3
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• pp.209-213
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• 2010

This paper describes the fabrication and characteristics of AlN piezoelectric MPG(micro power generator). The micro energy harvester was fabricated to convert ambient vibration energy to electrical power as a AlN piezoelectric cantilever with Si proof-mass. To be compatible with CMOS process, AlN thin film was grown at low temperature by RF magnetron sputtering and micro power generators were fabricated by MEMS technologies. X-ray diffraction pattern proved that the grown AlN film had highly(002) orientation with low value of FWHM(full width at the half maximum, $\theta=0.276^{\circ}$) in the rocking curve around(002) reflections. The implemented harvester showed the $198.5\;{\mu}m$ highest membrane displacement and generated 6.4 nW of electrical power to $80\;k{\Omega}$ resistive load with $22.6\;mV_{rms}$ voltage from 1.0 G acceleration at its resonant frequency of 389 Hz. From these results, the AlN piezoelectric MPG will be possible to suitable with the batch process and confirm the possibility for power supply in portable, mobile and wearable microsystems.

• New & Renewable Energy
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• v.2 no.3
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• pp.10-14
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• 2006

We have designed and fabricated coil structures by gold electroplating technique. The thickness, width, and length are $7{\mu}m,\;20{\mu}m$, and 1.6m, respectively. With vibrating a magnet on the surface of a fabricated electroplated coil, the micro power generator produce an alternating voltage. We have changed the vibrational frequency from 0.5Hz to 8Hz. The generated voltage was 106mV at 3Hz and 198mV at 6Hz. We have rectified and stepped up the input voltage using a quadrupler circuit. After using the step up circuit, the measured voltage was 81mV at 3Hz and 235mV at 6Hz.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.69-72
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• 2001

A novel water-turbine, Katamax, for micro hydropower generator is proposed, which has reasonable efficiency even in two meters of water head. The basic concept of Katamax is similar to that of waterwheel except that Katamax has two axis on which the blades rotate, where general waterwheel has only one. Brief structure and principles of Katamax are explained and analysis for efficiency of each module are provided. The result of the prototype product of Katamax is briefly explained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.69-72
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• 2001

A novel water-turbine, Katamax, for micro hydropower generator is proposed, which has reasonable efficiency even in two meters of water head. The basic concept of Katamax is similar to that of waterwheel except that Katamax has two axis on which the blades rotate, where general waterwheel has only one. Brief structure and principles of Katamax are explained and analysis for efficiency of each module are provided. The result of the prototype product of Katamax is briefly explained.