Temperature controller design for the temperature controlled stage based on the Peltier element
Controlled thermostats and temperature stages are applied in different applications such as scientific research, control of chemical reaction speed, thermal stabilization of CCD-matrix in digital cameras, laser wave-length stabilization, as well as food and drugs storage. There are thermostats and temperature stages of different size, power and structure. Advantages of the Peltier element include small weight, size and simple construction. However, the Peltier element is characterized by low energy conversion efficiency, low power in comparison with the compressor refrigerant circuit and a small temperature range in comparison with the resistive heater. The Peltier element can provide a working area temperature of the temperature stage above ambient or bellow ambient temperature. Usually, the Peltier element is applied in low power devices, where size and weight are limited. The Peltier element can be applied in designing automobile refrigerators, thermostats for biomaterials transportation in small amounts and for research on biophysical objects. Devices based on the Peltier element, can be applied for thermal massage of human skin or a thermal impact on various plants. For temperature stabilization and provision of high accuracy it is required to use a temperature controller for the temperature stage based on the Peltier element. Current has a control action on the Peltier element. Its value affects the working area temperature of the Peltier element. In this article, the application of an empiric identification of a mathematical model of the temperature stage based on the Peltier element is considered. The temperature controller synthesis by using the time-scale separation method and empiric adjustment for the temperature controlled stage based on the Peltier element is discussed in the paper. Diagrams of the thermal profile representation are showed. This temperature control system for devices based on the Peltier element can be used in generating temperature impacts on biophysical objects.