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2020 Vol.14, Issue 1 Preview Page

Research Article

Determination of Optimal Variables for Chilled Water Loop in Central Air-conditioning System using Genetic algorithms

유전알고리즘을 이용한 중앙공조시스템 냉수배관계의 최적제어 방법

Nam-Chul Seong1
,
Jee-Heon Kim2
,
Won-Chang Choi3*
성 남철1
,
김 지헌2
,
최 원창3*
1Research professor, Eco-system Research Center, Gachon University
2Researcher, Eco-system Research Center, Gachon University
3Professor, Department of Architect Engineering, Gachon University
1가천대학교 친환경시스템연구센터 연구교수
2가천대학교 친환경시스템연구센터 연구원
3가천대학교 건축공학과 교수
* Corresponding Author
28 February 2020. pp. 66-79
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Abstract

This paper suggests the real-time optimal control method of central air-conditioning system using chilled water. The control variables for optimization are differential pressure of the pump and the supply chilled water temperature supplied to the air conditioning system produced from the central chiller. The optimal control variables of the control point are calculated using genetic algorithm in one-hour time step. The objective function of algorithm was the energy consumption of the HVAC system, and the energy consumption was calculated using the mathematical model. The results of the operation of the normal mode under the initial design conditions and the optimal operation mode with the optimal control variables were evaluated by comparing the energy consumption of the HVAC system with the variation of the control volume at the control point selected in this study. As a result, the chilled water supply temperature of the chilled water loop was operated by changing between approximately 9°C and the differential pressure of the pump between 34.87 kPa and 78.91 kPa for the optimal control method. The total energy consumption of the HVAC system during optimal control operation was reduced by 16.98% compared to operation of the normal mode.

Keywords
Chilled water system
Supply chilled water temperature
Pump pressure difference
Optimal control
Genetic algorithm

키워드
냉수시스템
냉수공급온도
펌프차압
최적제어
유전알고리즘
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Information
  • Publisher :Korean Institute of Architectural Sustainable Environment and Building Systems
  • Publisher(Ko) :한국건축친환경설비학회
  • Journal Title :Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
  • Journal Title(Ko) :한국건축친환경설비학회논문집
  • Volume : 14
  • No :1
  • Pages :66-79
  • Received Date : 2020-01-02
  • Revised Date : 2020-02-20
  • Accepted Date : 2020-02-21
  • DOI :https://doi.org/10.22696/jkiaebs.20200007
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