Thermal control elements are devices with which we can regulate the intensity and direction of heat flow. When we change the thermal conductivity with an external input of energy other than heat, it is a thermal switch, but if the thermal conductivity changes with temperature, it is a thermal diode or heat regulator. Among the first are also Peltier devices, where it is a direct conversion of electric voltage into a temperature difference and vice versa. Based on the Peltier effect, thermoelectric thermal switches enable heat to be pumped in the desired direction. In the diploma thesis, we performed an experiment in which we tested thin-film Peltier elements in the way of later possible integration into a magnetic cooling device, as part of a structure with magnetocaloric material. In this case, the Peltier elements represent a heat switch with which we enable or interrupt the heat flow. This is made possible by the Peltier elements operating on the principle of the frequency of thermal pulsations. To perform a practical experiment, we designed a switching switch of Peltier elements, which allowed us to regulate any frequency and amplitude of the pulsating signal. We switched the toggle switch to a control that allowed us to easily operate the Peltier elements. The results show that a heat switch can transport large amounts of heat in extremely short time intervals.
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