Distributed Fan Control System Design Based On Fuzzy Control

With the development of control theory and power electronics technology,AC fan control technology is in the ascendant,and the application of AC fan speed control is gradually surpassing DC fan speed regulation.With the increasing maturity of frequency control technology,the development of AC speed regulation has been promoted.Although the frequency conversion speed regulation has a large speed regulation range and relatively good smoothness,the control system is relatively complicated and the cost is relatively high.In addition to variable frequency speed regulation,there is also a phase shift voltage regulation of the thyristor.By changing the conduction angle of the thyristor to control the effective voltage value of the fan,the speed of the fan is changed,but this speed regulation is The hardware circuit of the controller is relatively complicated,the cost is relatively high,and the function expandability is poor.Therefore,in order to overcome the above problems,this paper improves on the hardware circuit,and adds a fuzzy control algorithm based on the traditional PID control to make the speed control system more stable.Firstly,the mathematical model of each module of the AC fan is established,and the Matlab/Simulink simulation model is built by the mathematical model.When building a mathematical model,analyze the working principle of each module,deeply understand the relationship between input quantity and output quantity,and express the relationship between the two through mathematical formula.This paper focuses on the design process of fuzzy PID controller,and finally carries out simulation experiments.Through the comparison and analysis of simulation results,it is proved that the control effect of fuzzy PID is better than the traditional PID control.Secondly,build a hardware platform,design the overall plan according to the company's functional requirements,and carry out the software simulation experiment of the original theory and circuit.After the solution is determined,the PCB board is fabricated,and the hardware welding and debugging work is carried out.The chip of the host computer adopts the 32-bit STM32F103ZET6 chip,and the lower computer adopts the STC15W408AS chip as the control core.The design of the fan drive circuit and the selection of each module are introduced,and the development environment design of the LCD screen is adopted.The control interface,the communication mode between the upper computer and the lower computer is RS-485 serial communication.Finally,using the hardware platform of the design,comprehensive testing is carried out,and the speed regulation performance is evaluated according to the measured data of the fan speed,and then the monitoring function is evaluated according to the display effect of the liquid crystal screen.Through the system test,it is verified that the control system has good monitoring functions.