Research on water and fertilizer integration based on Fuzzy-PID control
For the control process of integration of water and fertilizer,the concentration of water and fertilizer solution presents char-acteristics,including nonlinearity and hysteresis.The traditional adjustment method shows low control accuracy and slow response speed,which can not meet the requirement of integration of water and fertilizer facing under the yellow sand substrate cultivation mode of facility agriculture in the Southern Xinjiang region.In order to solve the problem mentioned above,the Fuzzy-PID control strategy with parameter self-tuning was proposed and designed.In the Fuzzy-PID control strategy,according to the inputted error and the rate of error change,combined with fuzzy rules,three setting parameters Δkp,Δki,Δkd were outputted,which can achieve real-time adjust-ment of traditional PID control parameters.The results showed that compared to the traditional Fuzzy-PID control strategy,when the specific conductance of mother liquor is 7.2 mS/cm,the overshoot is decreased by 46.40%and the steady-state time is advanced by 39.05 s.Therefore,the designed Fuzzy-PID control strategy has good robustness,stability and response characteristic,which is help-ful for the requirement of integration of water and fertilizer facing the yellow sand substrate cultivation mode of facility agriculture.
integration of water and fertilizerFuzzy-PIDsimulation of Simulink