用于空调器系统仿真的高精度半经验压缩机模型研究

A High-Accuracy Semi-Empirical Compressor Model For Air-Conditioning System Simulation

为了在系统仿真软件中实现线性、高精度的压缩机试验数据拟合,本文开发了一种用于空调系统仿真的可线性拟合的高精度半经验压缩机模型。本文通过在流量模型的容积效率拟合公式中引入冷凝压力与蒸发压力多项式,克服了只采用冷凝与蒸发压力比例项计算容积效率导致精度低的难题;在功率模型中的压缩机效率拟合公式中,对比了用冷凝压力与蒸发压力的倒数项与一次项的拟合效果,得出了精度更高的功率拟合形式。案例验证结果表明,所选用的流量模型与试验数据的最大偏差小于2%,功率模型与试验数据的最大偏差小于3%,对试验数据的拟合精度较高;另外,流量及功率模型在非实验工况下的计算结果符合预期,外推能力得到了验证,能够在仿真过程中出现极端工况时保证迭代朝预期方向进行,适用于空调系统的系统仿真。

The objective of the high-accuracy semi-empirical compressor model developed in this paper is to accurately represent experimental compressor performance data using multi-linear regression. The proposed model adds discharge pressure and suction pressure to the mass flow rate correlation which is proved by case study to be able to improve accuracy on the previous pressure ratio correlation; as for electric power correlation,by comparing the fitting errors of using the first order and the inverse of discharge pressure and suction pressure in overall efficiency correlation,a higher accuracy electric power correlation is developed. The results show that,the maximum relative error on mass flow rate is less than 2%,and the maximum relative error on electric power is less than 3%. The experimental data are accurately fitted. Moreover,the results show that the outputs of the models of mass flow rate and electric power at the conditions outside the experiment data range are reasonable. The compressor model exhibit good extrapolation capability and can keep the iteration toward the right direction when it is out of the experimental range. The model is applicable for the simulation of air conditioning system.