• Title/Summary/Keyword: Power Generator

Search Result 3,850, Processing Time 0.041 seconds

Flow Characteristics and Wind Loads on the Solar Panel and Floating System of Floating Solar Generato (부유식 태양광 발전기의 패널과 부유체에 작용하는 풍하중과 유동특성)

  • Ryu, Dae-Gyeom;Lee, Kye-Bock
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.10
    • /
    • pp.229-235
    • /
    • 2019
  • A floating photovoltaic generation system is a new concept that combines existing photovoltaic generation technology with floating technology. This is installed in the water not on conventional land and a building. The system is designed as a unit module type that can be connected to other modules according to the power generation capacity, thereby forming a large-scale power generation facility. As a renewable energy source, it is composed of a floating structure, mooring device, photovoltaic power generation facility, and underwater cable. Because this system is installed outdoors, the effect of the wind load on the structure is very large. In this study, the wind loads most affected on the floating photovoltaic generation structure were obtained by computational fluid dynamic analysis. The flow characteristics and wind loads were analyzed for a range of wind orientations and angles of inclination. The analysis showed the position and magnitude of the maximum wind load to the wind direction and the flow characteristics around the solar panel and floating system. The wind load increased with increasing angle of inclination of the panel to the ground.

Design and Implementation K-Band EWRG Transceiver for High-Resolution Rainfall Observation (고해상도 강수 관측을 위한 K-대역 전파강수계 송수신기 설계 및 구현)

  • Choi, Jeong-Ho;Lim, Sang-Hun;Park, Hyeong-Sam;Lee, Bae-Kyu
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.5
    • /
    • pp.646-654
    • /
    • 2020
  • This paper is to develop an electromagnetic wave-based sensor that can measure the spatial distribution of precipitation, and to a electromagnetic wave rain gauge (hereinafter, "EWRG") capable of simultaneously measuring rainfall, snowfall, and wind field, which are the core of heavy rain observation. Through this study, the LFM transmission and reception signals were theoretically analyzed. In addition, In order to develop a radar transceiver, LFM transceiver design and simulation were conducted. In this paper, we developed a K-BAND pulse-driven 6W SSPA(Solid State Power Amplifiers) transceiver using a small HMIC(Hybrid Microwave Integrated Circuit). It has more than 6W of output power and less than 5dB of receiving NF(Noise Figure) with short duty of 1% in high temperature environment of 65 degrees. The manufactured module emits LFM and Square Pulse waveform with the built-in waveform generator, and the receiver has more than 40dB of gain. The transceiver developed in this paper can be applied to the other small weather radar.

Reliability and utility of a Dry Test Bench for testing the acoustic output from a ballistic shock wave therapeutic device (탄도형 충격파 치료기의 음향 출력 시험을 위한 Dry Test Bench의 신뢰성 및 유용성)

  • Jeon, Sung Joung;Lee, Min Young;Kwon, Oh Bin;Kim, Jong Min;Choi, Min Joo
    • The Journal of the Acoustical Society of Korea
    • /
    • v.41 no.5
    • /
    • pp.589-600
    • /
    • 2022
  • In order to verify the reliability of Dry Test Bench (DTB) used for testing the output energy from ballistic extracorporeal shock wave therapeutic devices, the measurements with DTB were compared with the acoustic energy measured with a Laser Doppler Vibrometer (LDV) for a commercial ballistic ESWT device. It was shown that the mechanical energy detected with DTB had variability maintained within 5 % at the same output power setting and also had a linear correlation (adj. R2 = 0.991) with the acoustic energy measured with the LDV for the entire output power settings. Using the correlation between the two methods and the correlation on the acoustic energy measured in between air and water with the LDV, the DTB measurement can be used to estimate the energy flux density in water with an average error of 7.85 % for the entire output power settings of the ballistic shock wave generator considered in the experiment. DTB provides information limited to the output mechanical energy and therefore it is not suitable for testing the various acoustic output parameters required in IEC61846 and IEC63045. However, DTB that is simple in measurement principles and easy to use is expected for manufacturers and clinical users to monitor the performance of ballistic Extracorporeal Shock Wave Therapy (ESWT) devices.

A Dual-Mode 2.4-GHz CMOS Transceiver for High-Rate Bluetooth Systems

  • Hyun, Seok-Bong;Tak, Geum-Young;Kim, Sun-Hee;Kim, Byung-Jo;Ko, Jin-Ho;Park, Seong-Su
    • ETRI Journal
    • /
    • v.26 no.3
    • /
    • pp.229-240
    • /
    • 2004
  • This paper reports on our development of a dual-mode transceiver for a CMOS high-rate Bluetooth system-onchip solution. The transceiver includes most of the radio building blocks such as an active complex filter, a Gaussian frequency shift keying (GFSK) demodulator, a variable gain amplifier (VGA), a dc offset cancellation circuit, a quadrature local oscillator (LO) generator, and an RF front-end. It is designed for both the normal-rate Bluetooth with an instantaneous bit rate of 1 Mb/s and the high-rate Bluetooth of up to 12 Mb/s. The receiver employs a dualconversion combined with a baseband dual-path architecture for resolving many problems such as flicker noise, dc offset, and power consumption of the dual-mode system. The transceiver requires none of the external image-rejection and intermediate frequency (IF) channel filters by using an LO of 1.6 GHz and the fifth order onchip filters. The chip is fabricated on a $6.5-mm^{2}$ die using a standard $0.25-{\mu}m$ CMOS technology. Experimental results show an in-band image-rejection ratio of 40 dB, an IIP3 of -5 dBm, and a sensitivity of -77 dBm for the Bluetooth mode when the losses from the external components are compensated. It consumes 42 mA in receive ${\pi}/4-diffrential$ quadrature phase-shift keying $({\pi}/4-DQPSK)$ mode of 8 Mb/s, 35 mA in receive GFSK mode of 1 Mb/s, and 32 mA in transmit mode from a 2.5-V supply. These results indicate that the architecture and circuits are adaptable to the implementation of a low-cost, multi-mode, high-speed wireless personal area network.

  • PDF

Measurement and Analysis of Propagation Characteristics in Curved Subway Tunnel Environments (곡선형 지하철 터널환경에서 전파 특성의 측정과 분석)

  • 정회동;박노준;강영진;송문규
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.29 no.8A
    • /
    • pp.950-961
    • /
    • 2004
  • In this paper, we measured and analyzed propagation characteristics in a subway tunnel that is recently increasingly becoming one of the radio communication environments. The measurements are carried out in a subway tunnel with frequency bands of 2.45㎓ and 5.8㎓. The length of tunnel we used for this study is 175m of LOS (Line-of-sight) and 270m of NLOS (Non Line-of-Sight). The subway tunnel is curved and its cross section is horseshoe type. The measurement systems we employ in this study are a narrow-band system and a wide-band system. The narrow-band system is used to get path loss measurement and the wide-band system is used to figure out delay profile measurement. In particular, the wide-band system consists of 1023 length PN sequence generator using a chip rate of 80MHz based on a sliding correlation technique. The omni-directional antennas and directional antennas are used to analyze propagation characteristics for beam type of antenna. The path loss displays only pure path loss of a tunnel environment. The delay profile indicates the mean excess delay and RMS (root mean square) delay spread.

Series-Type Hybrid Electric Bus Fuel Economy Increase with Optimal Component Sizing and Real-Time Control Strategy (최적용량매칭 및 실시간 제어전략에 의한 직렬형 하이브리드 버스의 연비향상)

  • Kim, Minjae;Jung, Daebong;Kang, Hyungmook;Min, Kyoungdoug
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.37 no.3
    • /
    • pp.307-312
    • /
    • 2013
  • The interest in reducing the emissions and increasing the fuel economy of ICE vehicles has prompted research on hybrid vehicles, which come in the series, parallel, and power-split types. This study focuses on the series-type hybrid electric vehicle, which has a simple structure. Because each component of a series hybrid vehicle is larger than the corresponding component of the parallel type, the sizing of the vehicle is very important. This is because the performance may be greater or less than what is required. Thus, in this research, the optimal fuel economy was determined and simulated in a real-world system. The optimal sizing was achieved based on the motor, engine/generator, and battery for 13 cycles, where DP was used. The model was developed using ASCET or a Simulink-Amisim Co-simulation platform on the rapid controller prototype, ES-1000.

A 40 MHz to 280 MHz 32-phase CMOS 0.11-${\mu}m$ Delay-Locked Loop (40MHz ~ 280MHz의 동작 주파수와 32개의 위상을 가지는 CMOS 0.11-${\mu}m$ 지연 고정 루프)

  • Lee, Kwang-Hun;Jang, Young-Chan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2012.05a
    • /
    • pp.95-98
    • /
    • 2012
  • This paper describes a multiphase delay-locked loop (DLL) that generates a 32-phase output clock over the operating frequency range of 40 MHz to 280 MHz. The matrix-based delay line is used for high resolution of 1-bit delay. A calibration scheme, which improves the linearity of a delay line, is achieved by calibrating the nonlinearity of the input stage of the matrix. The multi-phase DLL is fabricated by using 0.11-${\mu}m$ CMOS process with a 1.2 V supply. At the operating frequency of 125MHz, the measurement results shows that the DNL is less than +0.51/-0.12 LSB, and the measured peak-to-peak jitter of the multi-phase DLL is 30 ps with input peak-to-peak jitter of 12.9 ps. The area and power consumption of the implemented DLL are $480{\times}550{\mu}m^2$ and 9.6 mW at the supply voltage of 1.2 V, respectively.

  • PDF

Implementation of Multiple Frequency Bioelectrical Impedance Analysis System for Body Composition Analysis (신체 성분 분석을 위한 다 주파수 생체전기 임피던스 분석 시스템 구현)

  • Kim, Seong-Cheol
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.13 no.11
    • /
    • pp.5403-5408
    • /
    • 2012
  • In this paper, we introduce the multiple frequency bio-electrical impedance analysis method for body composition analysis. And then we implement the multiple frequency bio-electrical impedance analysis system. Overall system consists of: multiple frequency alternating current signal generator contained alternating current signal, phase signal detector, voltage signal detector, micro controller, in-out device(key-pad LCD), conductivity electrodes, system power. We explain the architecture of the system and required theory to implement the system. In order to investigate the clinical significance of the body composition data, compare to the data measured by the expert body composition analyzer which provide high reproduction and precision. Finally, experimental results which are the correlation between the measured data show the very high reproduction performance of the body composition analysis in the proposed system.

900MHz RFID Passive Tag Frontend Design and Implementation (900MHz 대역 RFID 수동형 태그 전치부 설계 및 구현)

  • Hwang, Ji-Hun;Oh, Jong-Hwa;Kim, Hyun-Woong;Lee, Dong-Gun;Roh, Hyoung-Hwan;Seong, Yeong-Rak;Oh, Ha-Ryoung;Park, Jun-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.7B
    • /
    • pp.1081-1090
    • /
    • 2010
  • $0.18{\mu}m$ CMOS UHF RFID tag frontend is presented in this paper. Several key components are highlighted: the voltage multiplier based on the threshold voltage terminated circuit, the demodulator using current mode, and the clock generator. For standard compliance, all designed components are under the EPC Global Class-1 Generation-2 UHF RFID protocol. Backscatter modulation uses the pulse width modulation scheme. Overall performance of the proposed tag chip was verified with the evaluation board. Prototype Tag Chip dimension is neary 0.77mm2 ; According to the simulation results, the reader can successfully interrogate the tag within 1.5m. where the tag consumes the power about $71{\mu}W$.

High Purity Hydrogen Generator for Fuel Cell Vehicles (연료전지 자동차 탑재형 고순도 수소생산장치)

  • Han, Jaesung;Lee, Seok-Min
    • Journal of Hydrogen and New Energy
    • /
    • v.12 no.4
    • /
    • pp.277-285
    • /
    • 2001
  • We developed a compact, 10 kWe, purifier-integrated reformer which supplies hydrogen for fuel cell vehicles. Our proprietary technologies regarding hydrogen purification by palladium alloy membrane and catalytic combustion by noble metal coated wire-mesh catalyst were combined with the conventional methanol steam reforming technology, resulting in higher conversion, excellent quality of product hydrogen, and better thermal efficiency than any other systems. In this system, steam reforming, hydrogen purification, and catalytic combustion take place all in a single reactor so that the whole system is compact and easy to operate. The module produces $8.2Nm^3/hr$ of 99.999% or higher purity hydrogen with CO impurity less than 10 ppm, which is equivalent to 10 kWe when PEMFC has 45 % efficiency. Thermal efficiency of the module is 81 % and the power density of the module is 1.6 L/kWe. As the results of experiments, cold-start time has been measured about 20 minutes. Response time of hydrogen production to the change of the feed rate has been within 1 minutes.

  • PDF