Modified pulse operation of thermoelectric coolers for building cooling applications

Abstract

This paper presents a modified pulse operation of the thermoelectric cooler (TEC) for building space cooling application. In the normal pulse operation of a thermoelectric cooler, a current pulse is given as the input, but in the modified pulse operation, along with the pulse current, the hot side heat transfer coefficient is also pulsed. A numerical model for the thermoelectric cooling system is developed assuming one-dimensional unsteady state heat transfer having convective heat transfer boundary condition at its hot side and constant heat flux boundary condition at its cold side. Then the thermoelectric cooling system is studied with variable pulse current ratio, cooling load, variable pulse width and with dissimilar pulse shapes. The result shows that, for a typical operating condition with the modified pulse operation, the thermoelectric cooling system can provide an average cooling power of 600W with the COP of 1.01, which are 23.3% and 2.12% higher than the normal mode of operation (i.e. without current pulse) respectively. This study also found that the rectangular-shaped pulse can provide higher average cooling power and COP when compared with the ramp and exponential pulse.