Research And Development Of Configurable Integrated Valves For Pipeline Water-saving Irrigation

As we all know,A lot of water for agriculture is used in China,but the water resource utilization rate is low,compared with some developed countries,it is still far apart.Since the beginning of the new century,our agricultural irrigation has gradually developed towards automation and informationization.The efficiency of irrigation water in irrigation districts has been greatly improved,and the idea of water-saving irrigation is deeply rooted in the hearts of the people.Under this guiding ideology,equipment such as irrigation district valve is being actively improved and under construction,with the aim of gradually transforming the existing artificially controlled irrigation system towards the direction of automation control.The automatic control of the irrigation district channel is the basis for the automation and informationization of the irrigation district.Among them,the valve is the most basic unit in the channel control system.Therefore,after studying the existing intelligent integrated valve operating mechanism and control method at home and abroad,combined with the current situation of existing agricultural canals and canals in China,this thesis proposes a configurable integrated valve for pipeline water-saving irrigation.Research and development.First of all,the thesis analyzes the significance of the integrated valve and the development trend at home and abroad to illustrate the necessity of the research.Secondly,the main structure of the system and the system modeling are introduced,and the feasibility of the model is verified by PSIM simulation.The system modeling mainly includes power module modeling and a sliding mode observer-based DC motor speed sensorless control method and its mathematical modeling.The power system modeling is mainly to realize the MPPT control of the photovoltaic module of the power supply module,and the speed sensorless control method is proposed to realize the adjustment control of the arbitrary opening of the DC motor.Subsequently,an integrated valve controller based on STM32F103C8T6 chip was designed.The hardware circuit includes the calculation of transformer,inductor and capacitor in the main circuit,A/D sampling,conditioning circuit,power switch(MOSFET)drive circuit and motor drive circuit.Circuit design of motor current sampling and protection circuit,auxiliary power supply,RS485 communication circuit and CPU minimum system.The software part includes main program design,PWM configuration,AD interrupt,RS485 communication,master program writing and algorithm optimization processing.Finally,the experimental verification and test results show that the valve controller designed implemented solar power management,valve adjustment control and Internet of Things communication.