On The Application Of The Prediction-ADRC In Water Supply System

With the social development as well as the progress of the era,people's living quality is improving constantly.Correspondingly,people's supply demands to water resources,which is closely related to their lives,is becoming higher and higher.In the current water supply system,there are problems as follows: the automation degree is very low;the water pressure control is inflexible.In order to solve the above problems,this thesis innovatively combines the dynamic matrix control in predictive control with the technology of Auto-Disturbance-Rejection Control(ADRC)and applies it to the water supply control system.Moreover,it is combined with pressure sensor and other devices to construct a constant pressure water supply system.Firstly,the structure and characteristics of constant pressure water supply system are analyzed,and the principle of constant pressure water supply is analyzed according to the pipe resistance characteristic curve of water supply system and pump head characteristic curve.Secondly,according to the running characteristic curve of pipe network and water pump,it expounds the water supply system's principle of variable frequency,speed regulation,and energy saving.Then,the basic principle of ADRC is introduced,applies it to the control of pump motor,designs the control system of pump motor on the basis of ADRC,and completes the adjustment of rotational speed.Finally,the basic principle of the dynamic matrix control is analyzed.Moreover,through the control scheme of water level of double water tank,it analyzes the influence of the selective parameters of Dynamic Matrix Control(DMC)on the control effect.On the basis of the advantages of ADRC and DMC,it puts forward a Prediction-ADRC scheme,and applies it to the constant pressure water supply system.In the Prediction-ADRC scheme proposed in this thesis,ADRC is applied to replace the traditional PID control to control the pump motor,and DMC is applied to achieve the purpose of adjusting in advance.In comparison with the control method of PID,the adjustment of the pump motor in ADRC owns the following advantages: the response speed is faster;the overshoot is smaller;the control effect is very ideal.In comparison with the Prediction-PID,adopting the strategy of the Prediction-ADRC owns the following advantages: the response time is reduced from 2s to 0.5s;in terms of anti-interference performance,the fluctuation produced in the control action is less,and the output curve of the system is smoother.In addition,the strategy of the Prediction-ADRC owns the ability to overcome the bad characteristics in the system,such as delay,which shows strong tracking performance and better anti-interference performance.