Optimal Design And Experiment Of Adaptive Electrostatic Spray Intelligent Charging System

China is a large agricultural country,with 350,000 T of chemical drugs used to control crop diseases and insect pests every year,but the utilization rate is less than40%.The low utilization rate of chemical spraying not only wastes resources,but also pollutes rivers and land,which brings a series of environmental problems and even endangers human health.The backwardness of spraying technology is the main reason for this phenomenon.Electrostatic spraying technology is widely recognized internationally as a new pesticide application which can effectively improve the utilization rate of pesticides.Based on the inductive charging method,the electrostatic spray electrode is optimized.The influence of electrical conductivity,electrostatic voltage and spray pressure on droplet charge ratio is explored.An adaptive high voltage electrostatic generator is designed,and a microprocessor controlled adaptive charging system is developed to improve the deposition rate and utilization rate of pesticide.The main research work is as follows:(1)Optimal design of imitation shape electrode.In order to improve the total charge of fog droplets,aiming at the working characteristics of TXVK-X series hollow cone nozzles,the influence of electrode form on charging effect was explored through mathematical deduction,and the electrode structure was optimized.The optimum parameters of imitation shape were further determined by COMSOL simulation analysis.(2)Mathematical modelling and interaction analysis of different factors.At present,the research on the influence law of charge to mass ratio in electrostatic spray theory is mostly limited to single factor analysis.Based on the study of the influence of conductivity,electrostatic voltage and spray pressure on charge to mass ratio,the mathematical model of charge to mass ratio is established.The interaction rule of different factors on charge to mass ratio is analyzed by Box-Behnken,and further enriched with static response.The best combination of different electricalconductivity and electrostatic voltage and spray pressure is optimized by using Design Expert 10.0.7.(3)Optimal design of adaptive high voltage electrostatic generator.In view of commercialized high voltage electrostatic generators,they can not be adjusted online by means of knob adjustment or constant voltage output.Besides,with the way of power input,it is necessary to add an inverter to the electrostatic spray spraying machine which is suitable for 24 VDC supply.It is cumbersome and wastes resources.This study adopts modular thinking to optimize the design and adaptively adjust the high-voltage electrostatic generator.The high voltage electrostatic generator takes the single chip computer as the control core,uses 24 VDC input,adjusts the tap position of the digital potentiometer AD5160 through the single chip computer,and uses the PI controller to fine-tune the PWM duty cycle,realizes the self-adaptive and precise regulation of 1-10 kV voltage.(4)Research and development of adaptive charging system.According to the electrostatic spraying system,the mixture ratio of the liquid and the mixture will lead to the change of electrical conductivity,which will affect the power charge and the target attachment effect of the electrostatic spray.The research is based on the large automatic driverless electrostatic sprayer,and develops a set of on-line adaptive adjustment of the charging system with the fluctuation of the mixing ratio.The system takes STM32F103C8T6 as the core,and adaptively controls the system according to the change of the conductivity of the liquid,and adaptively regulates the system by the electrostatic voltage and spray pressure control system,so as to display the adjustment effect in real time.The self-adaptive charging system with optimized design and installation was installed on the unmanned electrostatic spraying machine developed by Jiangsu provincial agricultural machinery promotion general station and Jiangsu University and the Yellow Sea Medical Equipment Co.,Ltd.in Nantong.The results showed that when the conductivity of the liquid liquid was 5 mS/cm,10 mS/ cm and 15mS/cm,compared with the unopened adaptive charging system,the electrostatic spraying spraying system was effective.The liquid deposition rate increased by18.08%,19.24% and 19.03% respectively,which indicated that the technology had good practical value and certain popularization significance.