• Title/Summary/Keyword: Control Relay

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Electrostatic Suspension System of Glass Panels using Relay Feedback Control (릴레이 제어법을 이용한 유리패널의 정전부상에 관한 연구)

  • Jeon, Jong-Up
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.6
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    • pp.71-79
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    • 2008
  • In the manufacture of flat panel display devices, there is a strong demand for contactless glass panel handling devices that can manipulate a glass panel without contaminating or damaging it. To fulfill this requirement, an electrostatic suspension device far glass panels where the glass panel is supported by electrostatic forces without any mechanical contact is proposed. To implement the system with low cost and compactness, switched-voltage control scheme that is based on the relay feedback control is utilized. Relay feedback control method deploys only a single high-voltage power supply that can deliver a DC voltage of positive and/or negative polarity and thus high voltage amplifiers that are costly and bulky are not needed any more. It is shown that despite the inherent limit cycle property of the relay feedback based control, an excellent performance in vibration suppression is attained due to the presence of a relatively large squeeze film damping originating from the electrodes and levitated object. Using this scheme, a $100{\times}100mm^2$ glass panel was levitated stably with airgap variation decreasing down to $1\;{\mu}m$ at an airgap of $100\;{\mu}m$.

Electrostatic Suspension System of Silicon Wafer using Relay Feedback Control (릴레이 제어법을 이용한 실리콘 웨이퍼의 정전부상에 관한 연구)

  • 전종업;이상욱;정일진;박규열
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.969-974
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    • 2003
  • A simple and cost-effective method for the electrostatic suspension of thin plates like silicon wafers is proposed which is based on a switched voltage control scheme. It operates according to a relay feedback control and deploys only a single high-voltage power supply that can deliver a dc voltage of positive and/or negative polarity. This method possesses the unique feature that no high-voltage amplifiers are needed which leads to a remarkable system simplification relative to conventional methods. It is shown that despite the inherent limit cycle property of the relay feedback based control, an excellent performance in vibration suppression is attained due to the presence of a relatively large squeeze film damping origination from the air between the electrodes and levitated object. Using this scheme, a 4-inch silicon wafer was levitated stably with airgap variation decreasing down to 1 $\mu\textrm{m}$ at an airgap of 100 $\mu\textrm{m}$

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Design of a Auto-Tuning Digital PID Controller using Relay feedback and Time Delay (시간 지연 릴레이 피드백을 이용한 자동동조 디지털 PID 제어기의 설계)

  • 류경모;박정일
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.109-109
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    • 2000
  • In process industries, more than 90% of the control loops have PID controller. Futhermore, the most control systems are using classical PID controllers for their process control. Various auto-tuning methods of PID gains using relay-feedback are presented recently. In order to get the desired control performance, the correct tuning of PID controller is very important. This paper suggests how to tune of digital PID gains using information for both the Nyquist critical point by conventional method and another point by the relay feedback and hidden time-delay term. Simulation results show that the proposed controller has better performance than the conventional method.

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Electrostatic Suspension System of Silicon Wafer using Relay Feedback Control (릴레이 제어법을 이용한 실리콘 웨이퍼의 정전부상에 관한 연구)

  • Lee, Sang-Uk;Jeon, Jong-Up
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.10 s.175
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    • pp.56-64
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    • 2005
  • A simple and cost-effective method for the electrostatic suspension of thin plates like silicon wafers is proposed which is based on a switched voltage control scheme. It operates according to a relay feedback control and deploys only a single high-voltage power supply that can deliver a DC voltage of positive and/or negative polarity. This method possesses the unique feature that no high-voltage amplifiers are needed which leads to a remarkable system simplification relative to conventional methods. It is shown that despite the inherent limit cycle property of the relay feedback based control, an excellent performance in vibration suppression is attained due to the presence of a relatively large squeeze film damping origination from the air between the electrodes and levitated object. Using this scheme, a 4-inch silicon wafer was levitated stably with airgap variation decreasing down to $1 {\mu}m$ at an airgap of $100{\mu}m$.

Implementation of Diagnostic Monitoring System for Auxiliary Relay (보조계전기의 진단 모니터링 시스템 구현)

  • Chang, Yong-Hoon;Nam, Jae-hyun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.709-711
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    • 2016
  • An automatic control system to control a machinery system is managed by the PLC(Program Logic Control) and measured a machinery status from the sensor information to improve productivity in the industry field. This paper to propose a diagnostic monitoring system consists of a relay module, a one-chip processor module and a computer monitoring system. To improve productive capacity, the system is to check an auxiliary relay's trouble by a real-time monitoring.

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A Study On the EMFG Representation of the Relay Circuits and Ladder Diagram

  • Kim, Hee-Jung;Paek, Hyung-Goo;Yeo, Jeong-Mo
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.124.4-124
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    • 2001
  • It needs a skillful experience to design and implement sequential circuits with a relay circuit or LD (Ladder Diagram). One makes out the operation of relay contacts sequentially in case of analyzing a relay circuit or LD. Still more, the design and analyzing of a complex relay circuit or LD are difficult. In this paper, we propose the EMFG (Extended Mark Graph) representation on relay circuits and LD.

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The Relay Circuit to EMFG Conversion with a Box´s Characteristic Equation

  • Goo, Paek-Hyung;Mo, Yeo-Jeong
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.60.5-60
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    • 2001
  • It is very difficult to design and analyze the relay circuit because one have to consider and analyze in order the behavior in which the relay contacts. In this paper, we propose the relay circuit to EMPG (Extended Mark Flow Graph) convension with a box´s characteristic equation. It will give you a lot of benefits in case of analysis and check of the relay circuit to convert the relay circuit into EMPG.

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The Relay Circuits Translation to EMFGs (릴레이 회로의 확장된 마크흐름선도 변환)

  • 여정모;백형구
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.11
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    • pp.952-957
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    • 2003
  • We propose how to translate relay circuits to the EMFGs(Extended Mark Flow Graphs) formally and analyze the original one by using the mark flow of it. Firstly, the concepts of the output condition, the output-on condition and the output-off condition are introduced in the relay circuits. These can be used to find the structure and the operation of respective relay outputs but the sequential operations of them cannot be obtained from these. Secondly, a relay circuit is translated to the corresponding EMFG as the all output-on conditions and all output-off conditions of it are translated to EMFGs. For the adequate translation, the condition arc and the concepts of the generation transition and the degeneration transition are introduced, and the duality for the simplification of the result. Thirdly, we analyze the operation of the original circuit by analyzing the mark flow of the resulting EMFG. We can achieve easy and fast analysis based on the EMFG's operation algorithm. Finally, we apply these to the relay circuit for an electric furnace and analyze its operation with the mark flow of the resulting EMFG. The formal translation from relay circuits to EMFGs makes the analysis easy so that these results can be used to design, modelling, the fault detection and the maintenance.

Semi-Analytical BER Evaluation Based on Error-Events at Relay Nodes for Decoded-and-Forward Relay Systems (복호 후 전달 릴레이 시스템의 평균 오류율에 대한 릴레이 노드에서의 오류 사건 기반의 의사-분석 기법)

  • Ko, Kyun-Byoung;Seo, Jeong-Tae
    • Journal of IKEEE
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    • v.15 no.1
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    • pp.64-69
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    • 2011
  • In this paper, a semi-analytical approach is proposed for decode-and-forward(DF) relay systems over rayleigh fading channels. At first, we derive the general form of the averaged bit error rate(BER) based on error-events at relay nodes in which a selection scheme is not used. It is confirmed that an erroneous detection and transmission at relay nodes can cause the degradation of the received signal-to-noise ratio (SNR) and the averaged BER performance. Furthermore, the proposed method can be extended to selective-DF(SDF) relay schemes so that it is verified to be another general solution for DF relay systems. Also, proposed semi-analytical expressions have been verified by comparing with simulations.

Traffic-Aware Relay Sleep Control for Joint Macro-Relay Network Energy Efficiency

  • Deng, Na;Zhao, Ming;Zhu, Jinkang;Zhou, Wuyang
    • Journal of Communications and Networks
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    • v.17 no.1
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    • pp.47-57
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    • 2015
  • With the ever growing demand of data applications, the joint macro-relay networks are emerging as a promising heterogeneous deployment to provide coverage extension and throughput enhancement. However, the current cellular networks are usually designed to be performance-oriented without enough considerations on the traffic variation, causing substantial energy waste. In this paper, we consider a joint macro-relay network with densely deployed relay stations (RSs), where the traffic load varies in both time and spatial domains. An energy-efficient scheme is proposed to dynamically adjust the RS working modes (active or sleeping) according to the traffic variations, which is called traffic-aware relay sleep control (TRSC). To evaluate the performance of TRSC,we establish an analytical model using stochastic geometry theory and derive explicit expressions of coverage probability, mean achievable rate and network energy efficiency (NEE). Simulation results demonstrate that the derived analytic results are reasonable and the proposed TRSC can significantly improve the NEE when the network traffic varies dynamically.