[Tianjin University of Technology] Simple electronic load Wang Zening

The CNC DC electronic load system is mainly composed of a constant current source control circuit, a high-precision A/D conversion circuit and a single-chip microcomputer control part. A control module is designed with the STM32F103RCT6 microcontroller chip as the core to achieve overall control of each module. The constant current source control circuit uses a hardware closed-loop current stabilizing circuit to achieve stable control of the output current. The A/D conversion circuit uses STM32 to achieve high-precision voltage and current measurement, and is combined with LCD to realize the display function of the system. A sliding rheostat is used to regulate the current. The design goal is to obtain an electronic load that can achieve constant current control. Its adjustment range is 0A ~ 1.5A, the maximum power is 30W, the display resolution is to three decimal places, and the error is within 5%. After testing, this system can fully complete all technical index requirements, and the actual working results meet the basic requirements of the question. The simple DC electronic load has constant current (CC) and constant voltage (CV) working modes, and can measure and digitally display the voltage at both ends of the electronic load in real time. Voltage, it can measure and digitally display the current flowing through the electronic load in real time, with high measurement accuracy and has overvoltage protection function.