Current controller design for Peltier element
Controlled thermostats are applied in many applications: scientific researches, chemical reaction speed control, thermal stabilization of CCD-matrix, stabilization of the laser temperature operating mode. Different construction, power and size of thermostat is exists. Executive element may be resistive heater, Peltier element, compressor refrigerant circuit. Peltier elements usually is applied for design of small power thermostats, small size thermostats because Peltier elements have small size and weight in comparison with compressor refrigerant circuit. Peltier element is allow to get above ambient temperature and bellow ambient temperature unlike resistive heaters. Thermoelectric thermostats is applied for thermostating CCD-matrix in digital camera, lasers, electronic component, biological materials, plants, drugs. Besides these thermostats is applied in scientific researches, medicine. It is possible to form temperature affect on plant seed for improvement plant seed quality, germination and energy germination. Besides It is impossible to apply the Peltier elements for forming temperature affects on plants during research of stress resistance by different external factors. Besides Peltier elements is applied in car refrigerators. It is required temperature controller for thermal stabilization and high accuracy. Controlling affect for Peltier element is current. Current value is influence on inside thermostat temperature. Therefore it is necessary to use the current controller. Technique of current controller design with PWM in control channel is discussed in this article. Circuit with Peltier element where it serially connected to bridge amplifier over smoothing filter is used. Controller design based on time-scale separation method. Computer simulation results for current control system are showed. This current controller may be to use in device for forming of temperature affect on biophysical objects.