Research On Pulse Electrochemical Micromachining System

Electrochemical machining has the advantages of a wide range of processing materials,no loss of tool electrodes,no cutting force,no deformation and no recast layer,etc.,and has broad application prospects in precision machining.In this Thesis,the pulse electrochemical micromachining system is researched for the needs of micro-electrochemical machining.First,on the basis of demand analysis,the overall scheme design is proposed,and the system hardware structure block diagram and software function block diagram are given.Then the pulse power supply was researched.Using the topological structure of "switching power supply + chopper circuit",designed electromagnetic interference filter circuit,power frequency rectifier filter circuit,double tube forward inverter circuit,high frequency transformer,output high frequency filter circuit,output voltage and current sampling circuit And chopping circuit.The amplitude,frequency and duty cycle of the output pulse can be adjusted.For the workpiece stage,according to the requirements,a suitable electronically controlled translation stage was selected,and its matching stepper motor drive circuit was designed.The control circuit and program of the system are developed using FPGA.Based on infrared input program,IIC driver,ADDA driver,DC power supply voltage adjustment program,chopper circuit pulse adjustment program,and stepper motor control program,a reliable human-computer interaction method and pulse power supply and stepper motor workpieces are realized Digital control of the station.In order to ensure the accuracy of output voltage control,a mathematical model of the doubletube forward circuit is established,and the limitations of conventional PID controllers are analyzed through simulation.Then,a fuzzy PID controller is used to achieve closed-loop control of the output voltage,which satisfies the output voltage control.Precision requirements.The commissioning of each module of the system was completed,and the electrochemical machining experiment of micro-pits and micro-grooves was carried out.The results showed that the system reached the expected goal.