Research On The WEDM Servo Driving System

With the development of science and technology, increasing precisiontooling and parts, wire cutting technology has been rapidly developed. Servodrive system is an important part of CNC system, directly affect the controlquality of the whole CNC system. In this paper, take the LS-WEDM machine asthe experimental platform, we analyzed the domestic and foreign wire cuttingmachine and driving control system development, and the hybrid stepping motorsubdivision driver of constant flow is developed, and designed the software andhardware.In this dissertation, we based on the stepping motor structure and workingprinciple were studied, according to the actual work requirements and theprinciple of subdivision driving, we designed a sine current subdivision and thesimulation circuit of the tracking control driver. In order to improve the positionaccuracy of stepping motor and frequency characteristics for the purpose, thedriver circuit of the hardware and software design. The controller is composedof a single chip computer numerical control part, constant current subdivisioncontrol part, the logical part, main drive part, current feedback and protectioncircuit. This design can be expected to achieve on the dynamic sinusoidalcurrent tracking, realize constant current,3file subdivision and positiveinversion control.Driver design has been completed, we made the no-load experiment ontwo-phase stepping motor, in line with the requirements of the actual machineconstant torque operation, the servo positioning accuracy, improve the frequencycharacteristics of stepping motor, and greatly reduce the step motor runningnoise, improving the maximum start frequency, we also made the load test Xaxis and cutting machine in the wire of the motor, stable operation, work table tomove smoothly, the processing requirements. Through the analysis on theexperimental waveforms and the result, the hardware and software design of the rationality is verified, consistent with the requirements of the servo system ofLSWEDM machine, two-phase stepping motor performance is significantlyimproved.