变浓度热泵实验系统自动控制研究

Automatic control for a heat pump system with variable compositions of mixture refrigerant

结合变浓度系统中的温度控制要求,对实验系统自动控制方案进行设计,并对控温程序采用LabVIEW7.0进行了编写。在软件设计的基础上进行了PID参数自整定调试及控温实验等。实验结果表明,冷凝器进水温度能准确地控制在设定温度的±0.1℃以内,蒸发器出口温度控制在设定温度的±0.3℃以内,从一个工况到另一个工况的过渡时间不大于15 min。控制程序可以较好地满足实验要求。

The control method was designed according to the requirement of control. A software pro- grammed with LabVIEW 7.0 was made for the experimental system. By the designed software, parameters of the PID algorithm were set up by PID autotuning VI. Temperature control experiments were conducted and the availability of the software was proved. The results show that the control accuracy of inlet temperature water to condenser and outlet temperature from evaporator of refrigerant were within ±0.1℃ and ±0.3℃ respectively. The interval of time from one steady state to another is less than 15 minutes. The accuracy of the temperature control meets the requirement of heat pump experimental researches.