Experimental assessment of precision temperature control electronic architecture for solar-powered TEC refrigerator

This study presents experimental research concerning an active thermoelectric cooling control architecture applied to portable, solar-powered medical refrigerators. A specialized Electronic Control Unit (ECU) has been devised for regulating thermoelectric cooling, enabling users to define operational thresholds for the thermoelectric coolers through the system's architecture. The TEC1-12706 thermoelectric cooling system was employed. The system is engineered to swiftly cool the medical refrigerator's storage cabinet by up to 6 °C within 30 minutes and maintain a critical temperature range of 2 °C to 8 °C, vital for safeguarding thermolabile vaccines and medications. The control unit design encompasses a closed-loop control approach utilizing an Arduino Nano, a Linear voltage regulator, and a solar-powered battery charging setup. The Arduino issues signals based on preset points through sensors, thereby regulating the refrigeration system's desired temperature, while a relay module serves as an ON-OFF controller for temperature management. Preliminary results affirm that, in conjunction with a heat sink and DC fan, the thermoelectric cooler successfully achieves the intended temperature range, demonstrating promising cooling capabilities.