Abstract: In order to solve the problems of large inertia, timevarying nonlinearity and pure delay in the traditional agricultural temperature control system, the thermostatic water bath temperature control system was studied, and the firstorder plus pure delay mathematical model was established of the temperature control mechanism. With full account of the advantages of PID control, fuzzy control and grey prediction control, the simulation evaluation showed that the mean value of the relative residual error of the grey prediction algorithm to predict the system temperature was 4.73×10-6, the variance ratio was 0.001 8, reflecting the high reliability of the model prediction; the cooperative temperature control model was designed with Fuzzy PID as the main controller and grey prediction algorithm as the auxiliary controller. The simulation results showed that the overshoot of the grey prediction Fuzzy PID controller was 0.35% lower than that of the traditional PID controller, and 0.18% lower than that of the Fuzzy PID controller; the adjusting time of the grey prediction Fuzzy PID controller was 232.8 ms shorter than that of the traditional PID controller and 204.9 ms shorter than that of the Fuzzy PID controller; compared with the traditional PID controller, the stable temperature value of the grey prediction Fuzzy PID controller decreased by 3×10-3 ℃, no change was detected when compared with the Fuzzy PID controller; for the same disturbance signal, the adjustment time of the grey prediction Fuzzy PID controller was 252.3 ms shorter than that of the traditional PID controller, and 248.2 ms shorter than that of the Fuzzy PID controller. The coordinated temperature control of constant temperature water bath based on grey prediction and Fuzzy PID, compared with traditional PID and Fuzzy PID control, had smaller overshoot, steady state error, faster regulation speed and better antiinterference performance.

Key words: grey prediction, Fuzzy PID, constant temperature water bath, dynamic response characteristics, anti interference capability

摘要： 为解决传统农业温控系统存在的大惯性、时变非线性和纯滞后性问题，以恒温水浴温度调控系统为研究对象，建立温度调控机构的一阶加纯滞后数学模型。充分考虑PID控制、模糊控制与灰色预测控制各自的优点，仿真评估灰色预测算法预测系统温度的相对残差均值为4.73×10-6，方差比为0.001 8，反映出模型预测的可靠性很高；设计将模糊PID作为主控制器，灰色预测算法作为辅助控制器的协同温度控制模型。仿真试验结果表明：灰色预测—模糊PID控制器的超调量相对于传统PID控制器下降0.35%，相对于模糊PID控制器下降0.18%；灰色预测—模糊PID控制器的调节时间相对于传统PID控制器缩短232.8ms，相对于模糊PID控制器缩短204.9ms；灰色预测—模糊PID控制器的稳定温度值相对于传统PID控制器减小3×10-3℃，相对于模糊PID控制器没有发生变化；对于相同的扰动信号，灰色预测—模糊PID控制器的调节时间相对于传统PID控制器缩短252.3ms，相对于模糊PID控制器缩短248.2ms。灰色预测与模糊PID的恒温水浴协同温度控制与传统PID、模糊PID控制相比，具有更小的超调量、稳态误差和更快的调节速度以及更好的抗干扰性能。

关键词: 灰色预测, 模糊PID, 恒温水浴, 动态响应特性, 抗干扰能力