多目标约束下半导体制冷片几何结构参数的优化设计

Optimizing the Geometric Structure of a Thermoelectric Cooler with Multi-objective Constraint

研究半导体制冷片几何参数的影响,往往设置固定的制冷片冷热端温度及输入电流。本文通过固定半导体制冷片外部的冷热端换热条件及输入电压,逐一分析了制冷片多个几何参数对制冷量、COP和制冷片冷端温度的影响,对每一个影响项的物理含义都给出了详细的说明,揭示了这些参量之间存在着的耦合关系。并在此基础上,综合制冷量、COP和制冷片冷端温度3个优化目标对制冷片几何参数选取范围的约束特性,提出了基于多目标优化的几何参数选择图,该图可快速清晰地得到不同需求下最佳的pn结几何参数。如在设置的边界条件下,当冷端温度需求为280 K,制冷量为15 W时,存在几何参数的最优解,而当冷端温度需求为240 K,制冷量为100 W时,则不存在可同时满足冷端温度和制冷量需求的几何参数。

The influences of the geometric parameters of a thermoelectric cooler on its cooling capacity and COP have been previously investigated under assumptions of a constant input current and fixed temperatures of hot/cold ends. However,in this paper,constant external heat exchanging conditions,instead of constant temperatures of hot/cold ends,were assumed,and the influence of each geometric parameter（ number of thermo-couples and the ratio of the length of a thermo-element to its cross-sectional area） on the cooling capacity,COP,and cold end temperature were analyzed. The physical implications of each effect are given in detail,revealing the coupling between these parameters. Based on the analyses,in addition to the constraints of the cooling capacity,the COP,and cold end temperature on the selection of the geometry parameters considered,a novel design diagram was developed for choosing the best geometric structure of thermoelectric coolers with a multi-objective constraint. This diagram can obtain the optimal geometry parameters under different requirements both quickly and clearly. For example,under the boundary conditions set in this paper,when the cold end temperature is 280 K and the cooling capacity is 15 W,there is an optimal solution to the geometric parameters. However,when the cold end temperature is 240 K and the cooling capacity is 100 W,there are no geometrical parameters that can satisfy both the cold end temperature and the cooling requirements.