Portable Intelligent Electromagnetic Flowmeter Controlled by Magnetic Induction Intensity

In this paper, we propose a portable intrinsically safe, intelligent electromagnetic flowmeter for the application of coal mines and provide a detailed description of its working principle. In terms of hardware circuit design, several important modules, including electromagnetic flow rate sensor, excitation circuit, core control circuit, signal conditioning circuit, and air traffic control detection circuit, were analyzed and designed in sequence. It adopts a high-performance, low-power MCU STM32407ZET6 and high-precision chips, ensuring measurement accuracy and reducing power consumption. The excitation method using low-frequency rectangular waves dynamically adjusts the sampling interval time, further prolonging the battery life. Finally, the performance of the electromagnetic flowmeter was measured, and the experimental data showed that the measured flow rate was basically linear with the output voltage. The relative indication error of the electromagnetic flowmeter was within 0.3%, and the repeatability fluctuated within the range of 0.03%. The flowmeter has good measurement accuracy, which is suitable for long-term use in coal mining environments.