Control and cooling of electronic load based on FET-transistor

The introduction of electronic load for testing high-precision low-voltage sources (solar panels) requires careful review not only of the circuit design, but also thermal and mechanical design. Modern advances in the development of solar cells and other low-voltage energy sources have led to the need to create compact and express systems for testing them, which cannot be implemented on existing solutions. The article considers the principle of creating and calculating the optimal solution for the implementation of electronic load. To achieve this goal, methods of analysis of modern electronic database, calculations of basic physical and electrical parameters and their modeling are used. Based on the considered physical and circuit solutions for the implementation of the electronic load unit, a corresponding electrical circuit was developed. The transistors are controlled by four unipolar operational amplifiers integrated into the LM324 chip. Control of the electronic load unit is implemented by controlling the voltage at the positive feedback terminals, which is further stabilized by the TL431 chip. The device is powered by a source of DC stabilized current of 12 V (provides additional filtering from voltage fluctuations). On the basis of the previously considered physical and circuit solutions for the implementation of the electronic load unit, its cooling and control system was developed. The calculation of the heat balance allows you to choose the right cooling system for stable operation of the system. The control of the electronic load unit is implemented using INA219 and Xicor X9C microcircuits, and a method for their calibration is proposed. These solutions will make it possible to create a universal electronic load solution for researching semiconductor devices and solar cells. Adherence to the indications and principles set out in this article will provide the load with the ability to work at high power, while maintaining good performance and reliability.