| Title |
A Study on the Operating Control of a Heat Pump System with Screw Compressors |
| Authors |
박준택(Jun-Tark Park) ; 이영수(Young-Soo Lee) ; 김지영(Jiyoung Kim) ; 채규정(Kyu-Jung Chae) ; 양희정(Hee-Jung Yang) |
| DOI |
http://dx.doi.org/10.6110/KJACR.2013.25.3.168 |
| Keywords |
스크류 압축기 ; 2단 압축 ; 열펌프 ; 오일 레벨 제어 Screw compressor ; 2-stage compression ; Heat pump ; Oil level control |
| Abstract |
A preliminary performance test of a 30RT 2-stage screw heat pump was carried out in order to develop a high performance large-scale unutilized energy source heat pump system, which will be used for district heating and cooling. In this study, two issues of the system operating control were investigated. The first issue is the mode switching control from 1-stage to 2-stage. A stable 2-stage heating operation is guaranteed, only if the load-side water inlet temperature is over a certain value, where the 1-stage heating operation should be done first from a cold start. The second issue is oil level control. An oil shortage problem in the low stage compressor, which depends on the degree of suction superheat, was solved by a proper oil level control scheme. |