Reliability control of a thermoelectric cooler with changes in ambient temperature

Abstract

The paper presents the development of method of thermoelectric system reliability indexes control for providing thermal modesof radio electronic equipment, based on thermoelectric coolers medium temperature variation. A mathematical model for investigating influence of the environment temperature variation on the reliability performance of a single-cascade thermoelectric cooler at a given temperature level of cooling, thermal load, geometry of thermoelement branches for different characteristiccurrent operating modes is considered. The results of calculations of the basic parameters, reliability indices, dynamic characteristicsand the analysis of dependences are given for revealing the peculiarities of control processes. It is shown that decreasing the medium temperature at a given chiller design decreases the operating current, increases the cold-productivity, and decreases the time of reaching a steady-state operating mode for various characteristic current operating modes. The time to steady-state operation decreases from the minimum failure rate to the maximum cooling capacity at a fixed medium temperature. The minimum steady-state operation time is ensured in maximum cooling capacity mode. Reduction of such significant for control indices as the amountof consumed energy for different characteristic current operation modes, required heat dissipation capacity of the radiator, time of reaching the steady-state mode is noted. Analysis of research results has shown that it is possible to control indicators of reliability of a single-stage cooler of a given design by changing the medium temperature by changing the value of operating current. A change in the medium temperature of the thermoelectric cooler due to an external supporting device makes it possible to vary the reliability indices and to find a compromise between the reliability, dynamics and cooling capacity of the thermal mode support system.