Liu Xuling, Yang Xin, Zuo Wensi, Bai Yunzhou, Zhou Hongbin, Wang Jie, Shao Jinggan, Shang Zhigang
School of electrical engineering, Zhengzhou University, Zhengzhou, 450001, China; School of mechanical and electronic engineering, Zhengzhou University of Light Industry, Zhengzhou, 450002, China.
Henan Xixi Highway Construction Co. LTD, Nanyang, 474450, China.
SLAS Technol. 2022 Oct;27(5):290-301. doi: 10.1016/j.slast.2022.06.002. Epub 2022 Jun 10.
A novel composite control method for actuated chamber air pressure of pneumatic microfluidic chip via a three-way electromagnetic microvalve is presented in this paper. The purpose of the control methods is to improve air pressure controlling precision for pneumatic control. By using the Bang-Bang (on-off) controller for pneumatic control, the step-response time, air pressure steady-state accuracy, and air pressure fluctuations are performed with different maximum thresholds and minimum thresholds. Moreover, by using the k (proportional ) plus PWM (Pulse-Width Modulation) control method for pneumatic control, the step-response time, air pressure steady-state accuracy, and air pressure fluctuations are performed with different carrier frequencies and carrier amplitudes. Both advantages and disadvantages of the two control methods are compared and analyzed based on the experimental data. According to the variable volume of the actuated chamber and the response characteristics of the three-way electromagnetic microvalve, the composite control method of the Bang-Bang plus k plus PWM is developed to control the actuated chamber air pressure. The experimental results show that when the absolute air pressure of the actuated chamber is set to 150kPa, the rising time is 69.3ms, which is about 8.0ms shorter than that of the k+PWM control method alone. The steady-state error is reduced from 0.90kPa to 0.65kPa, and the air pressure steady-state fluctuation is reduced from 1.60kPa to 0.90kPa, compared with the Bang-Bang control method alone.
本文提出了一种通过三通电磁微型阀对气动微流控芯片驱动腔室气压进行控制的新型复合控制方法。该控制方法的目的是提高气动控制中气压的控制精度。通过使用Bang-Bang（开关）控制器进行气动控制，在不同的最大阈值和最小阈值下对阶跃响应时间、气压稳态精度和气压波动进行了测试。此外，通过使用k（比例）加PWM（脉宽调制）控制方法进行气动控制，在不同的载波频率和载波幅度下对阶跃响应时间、气压稳态精度和气压波动进行了测试。基于实验数据对两种控制方法的优缺点进行了比较和分析。根据驱动腔室的可变体积和三通电磁微型阀的响应特性，开发了Bang-Bang加k加PWM的复合控制方法来控制驱动腔室的气压。实验结果表明，当驱动腔室的绝对气压设定为150kPa时，上升时间为69.3ms，比单独使用k+PWM控制方法缩短了约8.0ms。与单独使用Bang-Bang控制方法相比，稳态误差从0.90kPa降低到0.65kPa，气压稳态波动从1.60kPa降低到0.90kPa。
