| Title |
A Dynamic Simulation Model of Electronic-Expansion-Valve-Controlled Evaporators |
| Authors |
신영기(Younggy Shin) ; 조수(Soo Cho) ; 태춘섭(Choon-Seob Tae) ; 장철용(Cheol-Yong Jang) |
| Keywords |
비례적분 제어 ; 증발기 ; 전자팽창밸브 ; 동특성 모델 ; 과열도 ; 열펌프 PI ; Evaporator ; Electronic expansion valve ; Dynamic model ; Superheat ; Heat pump ; |
| Abstract |
Controlling superheat of indoor units associated with a multi-type heat pump is one of difficult tasks to be addressed. This study suggests a dynamic model of an evaporator based on heat and mass balance. Thermodynamic properties are calculated by a commercial software, Refprop. The model is programmed in MFC Visual C++ for controller interface in real-time mode. The simulation results shows that PI control works for a narrow range of superheat. Beyond the range, the temperature behavior of the refrigerant is quite nonlinear mainly due to phase change. Thus, it is concluded that PI control of superheat has to be supplemented by nonlinear control ideas to avoid saturation and excessive superheat. |