• Title/Summary/Keyword: High-speed pulse

Search Result 466, Processing Time 0.031 seconds

PWM Control of Hydraulic Motor Systems Using High Speed Solenoid Valves (고속응답 전자밸브에 의한 유압 모터계의 PWM 제어)

  • 김도태
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1999.10a
    • /
    • pp.387-392
    • /
    • 1999
  • The micro electronic control technology with developing microcomputers make great contribution to electrohydraulic control systems. The electrohydraulic pulse control simplifies in conjunction with power electronic amplifier and high speed operated solenoid valves. It is necessary to valves to convert electronic pulse signal to hydraulic pulse flow as fast as possible. This study deals with the speed control of an oil hydraulic motor operated by two way high speed solenoid valves. The valves acts as converters of electronic-pulse signals to hydraulic power. By constructing systems in which a hydraulic motor is operated by two solenoid valves, the pulse with modulation method (PWM) has adopted as the speed control of hydraulic motor systems. The static and dynamic characteristics of the systems are investigated by the experiment. It is clarify that a hydraulic motor operated PWM show good performance as a control component, achieving accurate velocity control.

  • PDF

Implement High Speed Bidirectional pulse power supply(BPPS) for plating

  • Kim, Tae-Eon;Park, Jong-Oh;Cho, Yong-Seong;Lee, Ihn-Yong;Kim, Young-Han;Lim, Young-Do
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.37.1-37
    • /
    • 2001
  • Electric plating is used in various industry field. Specially, pulse plating is able to deposit material at high current density compared to conventional DC plating. For example, pulse plating can get more fine grain, can improve adhesion and metal distribution and current efficiency, can reduce internal stress and crack. Therefore, we developed bidirection pulse power supply(BPPS) which has high speed pulse current and high current density and improve deposition quality and increase plating speed in this paper. BPPS(Bidirection pulse power supply) needs high speed rising time, falling time and output current accuracy. BPPS consists of rectifier part, chopper part, invertor part, and control part. Rectifier part changes outprt current direction.

  • PDF

High-Speed Characteristics of Plasma Display Panel using Priming Overlapping with Display Drive Method (표시기간 중첩 프라이밍 구동기술에 의한 플라즈마 디스플레이 패널의 고속구동특성)

  • Ryeom, Jeong-Duk
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.11
    • /
    • pp.2004-2009
    • /
    • 2007
  • A new high-speed drive method for the plasma display panel is proposed. In this method, the address period is inserted for the rest period of the sustain pulses and the priming pulse is applied on the entire panel at the same time overlapping with the sustain period. The ramp shaped priming pulse can be made with a simple drive circuit in this technology and the stable sustain discharge can be induced even by a narrow scan pulse in help of the space charge generated from the address discharge. From the experiments, it is ascertained that the priming pulse hardly influences the sustain discharge. Moreover, the voltage margin of the sustain discharge is almost constant though that of the address discharge broadens with narrowing the scan pulse width. And, if the time interval between the scan pulse and the sustain pulse is within $6{\mu}s$, the voltage margin of the address and the sustain discharges are unaffected though the applied position of the scan pulse is changed. High-speed driving with the address pulse of $0.7{\mu}s$ width was achieved and the address voltage margin of 20V and the sustain voltage margin of 10V were obtained.

Reducing Harmonics of the Next-generation High-speed Railway Inverter System by Random Pulse Position Modulation Technique based on Space Vector Modulation (Random Pulse Position PWM 방식을 적용한 IPMSM 기반 차세대 고속전철 구동 인버터 시스템의 고조파 저감)

  • Lee, Sang-Hyun;Jin, Kang-Hwan;Kim, Sung-Je;Kno, Ae-Sook;Kim, Yoon-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.26 no.6
    • /
    • pp.94-101
    • /
    • 2012
  • In this paper, The Next Generation High Speed Railway inverter system based on IPMSM drives using Random Pulse Position Modulation is proposed to reduce electromagnetic noise. To verify the validity of study, the simulator for the proposed system is designed and impplemented. Simulation program is developed using Matlab/Simulink. The simulation results of the proposed system was compared with the system using conventional method. The results show that the voltage and current harmonics of the proposed Next Generation High Speed Railway Inverter system. significantly decrease and spread into wide band area by the proposed Random Pulse Position modulation technique based on Space Vector Modulation method.

Control Strategy for High Speed Operation in Light Rail Transit (경량전철용 구동시스템의 고속영역운전을 위한 추진제어기법)

  • Lee Eun-Kyu;Choi Jae-Ho
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.53 no.10
    • /
    • pp.634-640
    • /
    • 2004
  • In this paper, the control strategy for high speed operation in light rail transit system is proposed. Recently, the vector control strategy is used to get high capacity control characteristic in low speed area. But Six step mode that is one pulse mode is used in high speed region to use DC link voltage to the maximum. Therefore, in high speed area, the vector control can not be used but scalar control method is used. To get a driving performance to be stabilized, the method of smooth mode change between the low speed and high speed area and PWM control is desired. So this paper proposes the control strategy using vector control include the one pulse mode. And also proposes overmodulation method that makes to change in one pulse mode softly. The performance of traction system will be verified by simulation results using MATLAB and experimental results.

Error Analysis of Reaction Wheel Speed Detection Methods (반작용휠 속도측정방법의 오차 분석)

  • Oh, Shi-Hwan;Lee, Hye-Jin;Lee, Seon-Ho;Yong, Ki-Lyuk
    • Journal of Astronomy and Space Sciences
    • /
    • v.25 no.4
    • /
    • pp.481-490
    • /
    • 2008
  • Reaction wheel is one of the actuators for spacecraft attitude control, which generates torque by changing an inertial rotor speed inside of the wheel. In order to generate required torque accurately and estimate an accurate angular momentum, wheel speed should be measured as close to the actual speed as possible. In this study, two conventional speed detection methods for high speed motor with digital tacho pulse (Elapsed-time method and Pulse-count method) and their resolutions are analyzed. For satellite attitude maneuvering and control, reaction wheel shall be operated in bi directional and low speed operation is sometimes needed for emergency case. Thus the bias error at low speed with constant acceleration (or deceleration) is also analysed. As a result, the speed detection error of elapsed-time method is largely influenced upon the high-speed clock frequency at high speed and largely effected on the number of tacho pulses used in elapsed time calculation at low speed, respectively.

Speed Control of High Speed Miniature BLDCM Based on Software PLL (소프트웨어 PLL 기반 소형 고속 BLDCM의 속도 제어)

  • Lee, Bong-Hee
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.14 no.2
    • /
    • pp.112-119
    • /
    • 2009
  • This paper presents a PLL(Phase Lock Loop) approach for effective speed and torque control of high speed miniature BLDCM(Brushless DC Motor) using hall sensor. The proposed speed control method based on PLL uses only a phase shift between reference pulse signal according to speed reference and actual pulse signal from hall sensor. It doesn't use any speed calculation, and calculates a direct current reference from phase shift. The current reference is changed to reduce the phase shift between reference and actual pulse. So the actual speed can keep the reference speed. The proposed control scheme is very simple but effective speed control is possible. In order to obtain a smooth torque production, the reference current is changed using acceleration and deceleration slope. The proposed control scheme is verified by experimental results of the 50W, 40,000[rpm] high speed miniature BLDCM.

Modeling and Simulation of New Encoding Schemes for High-Speed UHF RFID Communication

  • Mo, Sang-Hyun;Bae, Ji-Hoon;Park, Chan-Won;Bang, Hyo-Chan;Park, Hyung Chul
    • ETRI Journal
    • /
    • v.37 no.2
    • /
    • pp.241-250
    • /
    • 2015
  • In this paper, we present novel high-speed transmission schemes for high-speed ultra-high frequency (UHF) radio-frequency identification communication. For high-speed communication, tags communicate with a reader using a high-speed Miller (HS-Miller) encoding and multiple antennas, and a reader communicates with tags using extended pulse-interval encoding (E-PIE). E-PIE can provide up to a two-fold faster data rate than conventional pulse-interval encoding. Using HS-Miller encoding and orthogonal multiplexing techniques, tags can achieve a two- to three-fold faster data rate than Miller encoding without degrading the demodulation performance at a reader. To verify the proposed transmission scheme, the MATLAB/Simulink model for high-speed backscatter based on an HS-Miller modulated subcarrier has been designed and simulated. The simulation results show that the proposed transmission scheme can achieve more than a 3 dB higher BER performance in comparison to a Miller modulated subcarrier.

Software PLL Based Speed Control of High Speed Miniature BLDC (소프트웨어 PLL 기반 소형 고속 BLDC의 속도 제어)

  • Park, Tae-Hub;Seok, Seung-Hun;Lee, Dong-Hee;Ahn, Jin-Woo
    • Proceedings of the KIEE Conference
    • /
    • 2008.10c
    • /
    • pp.132-135
    • /
    • 2008
  • This paper presents a PLL(Phase Lock Loop) control method for speed control of high speed miniature BLDCM(Brushless DC Motor) using hall sensor. The Proposed PLL based speed control method uses a only phase shift between reference pulse signal according to speed reference and actual pulse signal from hall sensor. It doesn't use any speed calculation, and calculates a direct current reference from phase shift. The current reference is changed to reduce the phase shift between reference and actual pulse. So the actual speed can keep the reference speed. The proposed control scheme is very simple but effective speed control is possible.

  • PDF

Design and Output Characteristic of AC Pulse Current for MIG Welding of Ai Sheet (박판 Al MIG 용접용 AC펄스 전류 파형의 설계 및 출력특성)

  • 조상명;김태진;이창주;임성룡;공현상;김기정
    • Journal of Welding and Joining
    • /
    • v.21 no.2
    • /
    • pp.57-63
    • /
    • 2003
  • Since new types of vehicles or structures made from thin aluminum alloy are under rapid development and some products are already on the market, welding of aluminium sheet is increasing. MIG(Metal Inert Gas), MIG-Pulse, TIG(Tungsten Inert Gas) welding are the typical Ai welding. MIG welding has the advantage of high speed, but it is difficult to apply to the thin plate, because of bum-through by the high heat input and spatter. MIG-Pulse welding can weld without spatter and burn-through, but when the gap exists at the welding joint, there is quite a possibility of bum-through. TIG welding is difficult to weld at a high speed. AC Pulse welding alternates between DCEP(Direct Current Electrode Positive) and DCEN(Direct Current Electrode Negative). DCEN is higher wire melting rate than DCEP, while lower temperature of droplet than DCEP. In AC Pulse welding, far fixed welding current, wire melting rate increases as the EN ratio increases. For fixed wire feed rate, welding current decreases as the EN ratio increases. Because of these features, the temperature of droplet, the depth of penetration, the width of bead decrease and the reinforcement height increases as EN ratio increases, and these are able to weld at a high speed, lower heat input. It is the purpose of this study that design of AC pulse current waveform for MIG welding of Al sheet and estimation of output characteristic.