Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Statistical Analysis on Residuals from No-Fault Reference Models of a Residential Heat Pump System in Normal Cooling Operation

가정용 열펌프 시스템의 정상냉방 운전조건에서 기준모델에 의한 잔차의 통계적 분석

  • Kim, Min-Sung (New and Renewable Energy Department, Korea Institute of Energy Research) ;
  • Yoon, Seok-Ho (Energy Plant Research Division, Korea Institute of Machinery and Materials) ;
  • Baik, Young-Jin (New and Renewable Energy Department, Korea Institute of Energy Research)
  • 김민성 (한국에너지기술연구원 신재생에너지연구본부) ;
  • 윤석호 (한국기계연구원 에너지플랜트연구본부) ;
  • 백영진 (한국에너지기술연구원 신재생에너지연구본부)
  • Received : 2011.05.14
  • Accepted : 2011.09.23
  • Published : 2011.12.01
Download PDF
⟨ Previous Next ⟩

Abstract

To approximate the threshold of the fault detection and diagnosis (FDD) system, validation of the measurements is mandatory. Naturally, the system shows uncertainties due to measuring sensors - mostly thermocouples or RTDs - and due to repeatability. The uncertainty of a thermocouple comes from natural variation or a drift of the thermocouple measurement. Considering the natural variation behaves like zero-mean white noise, its natural variation can be characterized closely by the steady-state standard deviation. However, residuals between measurements and no-fault references in FDD systems show a statistical distribution with various uncertainties. In this paper, steady-state variations of measurement residuals were investigated by utilizing built-in temperature sensors in a heat pump for the model development and the final application.

열펌프의 고장감지 및 진단을 위하여 측정값에 대한 분석은 필수적이다. 열펌프의 고장감지는 열전대 등의 온도센서로 수행되는데, 재연성과 센서자체의 오차에 의해 시스템의 정상상태 측정값들은 통상 백색 노이즈의 형태로 존재한다. 고장감지 및 진단시스템을 구축하기 위하여 이상적인 정상상태를 정의하는 기준모델을 추출하게 되는데, 실제 측정값과 모델에 의한 기대값은 수학적 편차, 즉 잔차가 필연적으로 존재하게 된다. 이러한 잔차는 운전조건에 따라 변화하며, 다양한 불확실도를 포함한 확률분포를 갖게 된다. 본 연구에서는 온도센서를 활용하여 정상상태 진단을 수행하고 이를 기반으로 기준모델을 도출하였다. 이후 실측값과 기준모델과의 잔차를 통계적으로 분석하여 고장여부를 판단하는 경계값을 산출하였다. 본 분석에 의하여 열펌프의 고장감지 및 진단시스템의 개발을 위한 불확실도와 경계값을 통계적으로 계산함으로써 진단결과의 확률적 신뢰성을 보장할 수 있는 방법론을 제공하였다.

Keywords

References

  1. Proctor, J., 2004, "Residential and Small Commercial Central air Conditioning; Rated Efficiency isn't Automatic," Presentation at the Public Session. ASHRAE Winter Meeting, Jan. 26, Anaheim, CA.
  2. Breuker, M. S., Braun, J. E.. 1998, "Evaluating the Performance of a Fault Detection and Diagnostic System For Vapor Compression Equipment," Int. J. of HVAC&R Research, Vol. 4, No. 4, pp. 401-425. https://doi.org/10.1080/10789669.1998.10391412
  3. Kim, M., Payne, W. V., Domanski, P. A., and Hermes, C. J. L.. 2006, "Performance of a Residential Heat Pump Operating in the Cooling Mode with Single Faults Imposed," NISTIR 7350, National Institute of Standards and Technology, Gaithersburg, MD, USA.
  4. Rossi, T. M., 1995, Detection, Diagnosis, and Evaluation of Faults in Vapor Compression Cycle Equipment, Ph.D. Dissertation, Purdue Univ., West Lafayette, IN, USA.
  5. Glass, A. S., Gruber, P., Roos, M., and Todtli, J.. 1995, "Qualitative Model-Based Fault Detection in Air-Handling Units," IEEE Control Systems Magazine, Vol. 15, No. 4, pp. 11-22. https://doi.org/10.1109/37.408465
  6. Li, H., 2004, A Decoupling-Based Unified Fault Detection and Diagnosis Approach for Packaged Air Conditioners, Ph.D. Dissertation, Purdue Univ., West Lafayette, IN, USA.
  7. Kim, M, Payne, W. V., Domanski, P. A., and Yoon, S. H., 2008, "Design of a Steady-State Detector for Fault Detection and Diagnosis of a Residential Air Conditioner," Int. J. of Refrigeration, Vol. 31, No. 5, pp. 790-799. https://doi.org/10.1016/j.ijrefrig.2007.11.008
  8. Kim, M., Yoon S. H., Payne, W. V. and Domanski, P. A., 2010, "Development of the Reference Model for a Residential Heat Pump System for Cooling Mode Fault Detection and Diagnosis," Journal of Mechanical Science and Technology, Vol. 24, No. 7, pp. 1481-1489. https://doi.org/10.1007/s12206-010-0408-2