Research On Power Supply And Control System Of Multigroove Synchronous Processing Wire EDM Machine

In order to solve the problems of low efficiency and uneven distribution of internal stress in block cutting of tire mould,the multi-groove synchronous wire EDM machine tool was invented and developed by the research group.In order to solve the problems of power cost and volume,current crosstalk existing in each station and control difficulties,this paper designed a multi-channel time-sharing output pulse power supply and a special servo control system according to the working principle of multi-slot synchronous wire EDM machine tools.Through the relevant process experiments,the feasibility and superiority of the pulse power supply and control system were proved,the multi-groove cutting processing law was summarized,and efficient processing of four-stations was realized.The paper firstly optimized the mechanical structure of the machine tool,designed the easy threading mechanism,tensioning device,and four-station symmetrical liquid supply system.The new machine tool adopts the single-wire four-station synchronous processing mode.In order to reduce the cost of the power supply,the volume of the power supply,and reduce the crosstalk current between the stations,the paper designs a multi-channel time-sharing output pulse power supply,which uses one power supply for the four-station.The power supply is mainly composed of four parts: the main circuit,the chopper circuit,the detection circuit,and the auxiliary power supply.According to the working characteristics of the new machine tool,the performance index of the pulse power supply was determined: the output phase difference of the four channels is ? / 2,and the pulse width of is adjustable from 1 to 200 ?s,The duty ratio is adjustable from 0 to 1,the output voltage is adjustable from 0 to 120 V,the output current is adjustable from 0 to 10 A,and the maximum output power is 1200 W.Through parameter calculation and core device selection,the hardware circuit design was completed.Taking STM32 single-chip microcomputer as the core of power control,a pulse power control program was written and debugged in C language.Finally,a dedicated fourway time-sharing output pulse power was developed.In response to the insufficient performance of the original control system,a dedicated servo control system was developed.Control performance requirements were clarified,key electrical components were selected,and circuit schematics were designed.In order to take into account both stability and adjustment speed,the multi-groove machine tool adopts PID adjustment as the main,combined with a linear function control scheme.The PLC control program and a human-computer interaction interface were written.Modbus and TCP protocols were applied respectively to solve the communication problems between PLC,pulse power supply and touch screen.Finally,relevant process experiments were carried out.The groove width and processing speed were used as evaluation indicators to study the effects of output voltage,pulse width,duty cycle,and wire speed on the processing of Q235 steel.First,a single-station experiment was carried out to study the changing laws of processing speed and slot width under different factor levels,and the feasibility of the dedicated servo control system was verified.Then,twostation and four-station orthogonal experiments were conducted respectively to explore the multi-slot synchronous processing rule.Finally,four-station stable and efficient processing was realized.