有色设备

The paper introduces a control method for the inlet water regulating valve of the heat exchanger in the vacuum swing adsorption (VPSA) oxygen production process. Firstly, it briefly describes the complex characteristics of temperature control in the VPSA adsorption tower, including large lag and sensitivity to environmental temperature. Then, it analyzes the shortcomings of conventional PID control in VPSA temperature regulation and proposes the use of a fuzzy self-tuning PID parameter method. Finally, it is implemented using Siemens 1500 PLC and the WinCC software from ABB. Taking a VPSA device as an example, by adjusting the proportional coefficient, differential action, and integral action, two temperature control curves were obtained. The results show that conventional PID temperature control fluctuates by approximately 10℃ when the environmental temperature changes sharply, and has a large overshoot. Moreover, due to the selection of the integral parameter no longer being applicable, the temperature deviates significantly from the set temperature at night. In contrast, the fuzzy self-tuning PID control responds faster to temperature changes, has an overshoot of 5%, and the temperature curve is closer to the set value and is adjusted promptly. Compared to traditional PID control, the fuzzy self-tuning PID control has a smaller overshoot during extreme temperature changes and a more stable temperature change trend after the heat exchanger.