Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
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Real-time Distributed Control in Virtual Device Network with Uncertain Time Delay for Predictive Maintenance (PM)

가상 디바이스 네트워크상에서 불확실한 시간지연을 갖는 실시간 분산제어를 이용한 예지보전에 관한 연구

  • Kiwon Song (Department of Electrical Engineering, University of Seoul) ;
  • Gi-Heung Choi (Department of Mechanical Systems Engineering, Hansung University)
  • Published : 2003.09.01
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Abstract

Uncertain time delay happens when the process reads the sensor data and sends the control input to the plant located at a remote site in distributed control system. As in the case of data network using TCP/IP, VDN that integrates both device network and data network has uncertain time delay. Uncertain time delay can cause degradation in performance and stability of distributed control system based on VDN. This paper first investigates the transmission characteristic of VDN and suggests a control scheme based on the Smith's predictor to minimize the effect of uncertain varying time delay. The validity of the proposed control scheme is demonstrated with real-time velocity control of DC servo motor located in remote site.

원격지에 위치한 분산제어 시스템과 센서 데이터 또는 제어 명령을 주고받을 때에는 불확실한 시간지연이 발생한다. TCP/IP 프로토콜을 이용한 데이터 네트워크와 마찬가지로 데이터 네트워크와 디바이스 네트워크를 결합한 가상 디자이스 네트워크도 불확실한 시간지연이 내재되어 있다. 이러한 시간지연은 분산제어시스템의 성능을 저하시키고 불안전성을 야기하는 원인이 된다. 본 논문에서는 이러한 네트워크상에 내재하는 시간지연을 평가하고 부정적인 효과를 최소화하기 위하여 Smith Predictor를 적용하였다. 제안된 제어 알고리즘은 실시간 서보제어를 통하여 효과를 입증하였으며 가상 디바이스 네트워크 개념에 근거한 분산제어 시스템을 이용하여 실시간 예지보전을 수행할 때 효과가 있음을 제시하였다.

Keywords

References

  1. M. S. Branicky, S. M. Phillips, and Wei Zhang, 'Stability of Networked Control Systems: Explicit Analysis of Delay', Proc. ACC, Chicargo, Illinois, pp. 2352-2357, June, 2000
  2. Wei Zhang, M. S. Branicky, and S. M. Phillips, 'Stability of Networked Control Systems', IEEE Control Systems Magazine, pp. 84-99, February 2001
  3. Feng-Li Lian, James Moyne, and Dawn Tilbury, 'Network Design Consideration for Distributed Control Systems' IEEE, pp. 297-307, March 2002
  4. G. H. Choi, G. S. Choi, and J. S. Kim, 'LonWorks based Virtual Device Network (VDN) for Predictive Maintenance', ICMITOl, Yamaguchi Seminar Park, Japan, pp. 372-376,2001
  5. G. H. Choi, 'Transmission Characteristics in Lon Works/IP based Virtual Device Network for Predictive Maintenance', J. KIIS, Vol. 18, No-4, pp
  6. J. W. Park and J. M. Lee, 'Design and Implementation of Internet based Teleoperation Control System', ICCAS2001, pp. 452-455, 2001
  7. Ki Won Song, Gi Sang Choi, Gi Heung Choi, and Jung Soo Kim, 'LonWorks-based Virtual Device Network (VDN) for Predictive Maintenance', International Journal of Applied Electromagnetics and Mechanics 11, pp. 1-13, November, 2000, JAE275 I0S Press
  8. Weidong Zhang and Xiaomong Xu, 'Simple Predictor for Processes with Time Delay', Proc.AACC, San Diego, Califonia, pp. 822-826, June, 1999
  9. Saverio Mascolo, 'Smith's Predictor for Congestion Control in High-Speed Data Networks', IEEE, pp. 358-364, February 2000