CO2水源热泵全工况性能分析与最优过热度确定
Full-range performance analysis of CO2 water-source heat pump and determination of optimal degree of superheat
摘要：
在跨临界CO2水源热泵实验研究的基础上，借助于神经网络拟合模型，综合分析了热泵在全工况范围内及不同控制参数下的运行特性，总结了系统的制热性能系数、制热量和过热度对热源温度、供/回水温度和电子膨胀阀开度变化的敏感度。结果表明，热源温度的影响最大，单位温度变化所引起的制热性能系数变化幅度超过0.2，制热量最大变化幅度超过4 kW，过热度变化幅度超过 1 ℃。给出了最优过热度与供/回水温度和热源温度的拟合公式，为热泵系统电子膨胀阀PID控制最优目标过热度的设定提供了参考。
Abstract：
Based on the experimental study on transcritical CO2 water-source heat pump and neural network fitting model, systematically analyses the performance characteristics of the heat pump under full-range operating conditions as well as different control strategies, and summarizes the sensitivity of the system COP, heating capacity and degree of superheat to the heat source temperature, the water supply/return temperature and the open degree of electronic expansion valve. The results show that the heat source temperature has the largest influence on the system performance, and the maximum change of COP, heating capacity and degree of superheat with respect to unit heat source temperature exceeds 0.2, 4 kW and 1℃ respectively. The optimal degree of superheat is fitted as a linear function of the heat source temperature and water supply/return temperature. Gives the fitting formula, providing the reference for setting of the optimal degree of superheat for PID control of the heat pump system.
Keywords:CO2, water-source heat pump, full-range performance, neural network, optimal degree of superheat, coefficient of performance, heating capacity, heat source temperature