| Title |
Practical Modeling and PI Controller Design for Centrifugal Water Chillers |
| Authors |
Seok-Kwon Jeong ; Sung-Joon Han ; Young-Mi Jung |
| DOI |
http://dx.doi.org/10.6110/KJACR.2015.27.4.187 |
| Keywords |
터보냉동기 ; PI제어 ; 용량제어 ; 실용 모델 ; 증발압력제어 Centrifugal water chiller ; Capacity control PI control ; Practical model ; Evaporating pressure control |
| Abstract |
This paper describes the PI controller design based on a practical transfer function model for centrifugal water chillers. The rotational speed of a compressor and the opening angle of an electronic expansion valve were simultaneously regulated as manipulated variables to maintain temperature reference and to ensure high efficiency of the chiller. The COP according to the change in each variable was investigated by performing some static experiments, and it was reflected in the PI controller design to accomplish the high efficiency control. Especially, the practical transfer function model of the chiller was built based on the dynamic experimental data considering the strong inherent non-linearity and complexity of the chiller system. The validity of the designed PI controller was proven by some experimental results using the test facility and the results were also compared to the conventional evaporating pressure control results. |