Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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A Performance Analysis on a Chiller with Latent Thermal Storage According to Various Control Methods

잠열 축열식 칠러시스템의 제어 방식에 따른 성능 분석

  • Kang, Byung Ha (School of Mechanical Engineering, Kookmin University) ;
  • Kim, Dong Jun (Department of Mechanical Engineering, Graduate School, Kookmin University) ;
  • Lee, Choong Seop (Department of Mechanical Engineering, Graduate School, Kookmin University) ;
  • Chang, Young Soo (School of Mechanical Engineering, Kookmin University)
  • 강병하 (국민대학교 기계공학부) ;
  • 김동준 (국민대학교 대학원 기계공학과) ;
  • 이충섭 (국민대학교 대학원 기계공학과) ;
  • 장영수 (국민대학교 기계공학부)
  • Received : 2017.08.22
  • Accepted : 2017.09.28
  • Published : 2017.11.10
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Abstract

A chiller, having a thermal storage system, can contribute to load-leveling and can reduce the cost of electricity by using electricity at night. In this study, the control experiments and simulations are conducted using both conventional and advanced methods for the building cooling system. Advanced approaches, such as the "region control method", divide the control region into five zones according to the size of the building load, and determines the cooling capacities of the chiller and thermal storage. On the other hand, the "dynamic programming method" obtains the optimal cooling capacities of the chiller and thermal storage by selecting the minimum-cost path by carrying out repetitive calculations. The "thermal storage priority method" shows an inferior chiller performance owing to the low-part load operation, whereas the chiller priority method leads to a high electric cost owing to the low utilization of thermal storage and electricity at night. It has been proven that the advanced control methods have advantages over the conventional methods in terms of electricity consumption, as well as cost-effectiveness. According to the simulation results during the winter season, the electric cost when using the dynamic programming method was 6.5% and 8.9% lower than that of the chiller priority and the thermal storage priority methods, respectively. It is therefore concluded that the cost of electricity utilizing the region control method is comparable to that of the dynamic programming method.

Keywords

References

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