Abstract: In order to solve the problems of long steadystate time and large overshoot of Potential of Hydrogen (pH) and Electrical Conductivity (EC) in the process of fertilizer and water proportioning, the three gain parameters (proportional, integral and differential) of the controller are effectively optimized by incorporating the sparrow search algorithm on the basis of fuzzy PID control. Simulation experiments of traditional PID control of pH and EC values, simulation experiments of fuzzy PID control of pH and EC values, and simulation experiments of fuzzy PID control of pH and EC values optimized based on sparrow search algorithm are done respectively under MATLAB/Simulink, and the stabilization time of pH and EC values as well as the amount of overshooting in the three simulation experiments are compared. The experimental results show that the stabilization time of pH and conductivity are reduced by 475 s and 261 s, and the overshoot is reduced by 5.4% and 12.19%, respectively, compared with the traditional PID control by the fuzzy PID control optimized based on the sparrow search algorithm, and the stabilization time of pH and conductivity are reduced by 356 s and 95 s, respectively, and the overshoot is reduced by 1.4% and 2.34%, respectively. The control method proposed in this paper enables the system to have smaller overshoot and faster time to reach the rising steady state, which can precisely control the fertilizer and water ratios.

Key words: water and fertilizer integrated control system, fuzzy PID control, sparrow search algorithm, pH, electrical conductivity

摘要： 为解决肥料和水的配比过程中，酸碱度(pH)和电导率(EC)的稳态时间长、超调量大等问题，在模糊PID控制的基础上融合麻雀搜索算法对控制器的三个增益参数(比例、积分、微分)进行有效优化。在MATLAB/Simulink下分别做传统PID控制pH和EC值的仿真试验、模糊PID控制pH和EC值的仿真试验以及基于麻雀搜索算法优化的模糊PID控制pH和EC值的仿真试验，将三者仿真试验中pH和EC值的稳定时间以及超调量进行对比。试验结果表明：基于麻雀搜索算法优化的模糊PID控制与传统的PID控制相比，酸碱度和电导率的稳定时间分别减少475 s和261 s，超调量分别减少5.4%和12.19%，与模糊PID控制相比，酸碱度和电导率的稳定时间分别减少356 s和95 s，超调量分别减少1.4%和2.34%。所提出的控制方法能够使系统具有更小的超调量和更快地达到上升稳态时间，可以精准的控制肥料和水的配比。

关键词: 水肥一体化控制系统, 模糊PID控制, 麻雀搜索算法, 酸碱度, 电导率