Research On Edge Controller Of Reflow Oven

As electronic products continue to develop in the direction of small size,powerful function,good stability and high integration.In the production process of electronic product circuit board,surface mount technology(SMT)plays a vital role.Reflow oven as an important welding equipment in surface mount technology,can realize thousands of solder joints in a short time,realize the electrical connection of printed board and components.This thesis designs and develops a reflow oven-based edge controller for the VRF630 reflow oven,addressing the problems of poor control methods,poor control accuracy and automation,and inability to communicate with this reflow oven controller.The edge controller performs real-time acquisition,closed-loop control,and remote communication of reflow oven production process parameters in the field,collecting,calculating,and controlling at the source of data generation.The main studies are as follows:(1)According to the function of the edge ware,the hardware circuit based on reflow oven edge controller is designed and the circuit working principle is described.With STM32F407ZET6 microcontroller as the core of information processing,this paper focuses on the design method of temperature acquisition module and temperature control unit,and BC26 is selected as the wireless communication module to upload the data.(2)The control method of reflow oven is studied,the transfer function of the controlled object is obtained,and the Smith predictor and fuzzy PID control algorithm are designed to control the temperature.The Smith estimator,fuzzy PID control algorithm,fuzzy PID control algorithm and conventional PID control algorithm are simulated and compared in Matlab.The simulation results verify that the Smith estimator and fuzzy PID control algorithm have the smallest overshoot,the shortest regulation time and the strongest anti-interference capability in reflow oven temperature control.(3)Keil u Vision5 was used as the platform for the program design.It mainly includes the acquisition and filtering program,temperature control program,and wireless communication program.(4)In order to verify the feasibility of the research in this thesis,the development of the physical reflow oven edge controller and the construction of the cloud platform were carried out.The edge controller was used to collect temperature data in real time in the field and uploaded to the cloud platform for display.The algorithm uses Smith predictor with fuzzy PID algorithm to remotely control the temperature according to the temperature command downlinked from the cloud,realizing the function of uploading the temperature data from the site to the cloud and the control command downlinked from the cloud to the site.This project embodies the concept of edge computing data upstream and computing downstream.