On Pulse Generator Technique Of Electric Discharge Machining

Aiming at the features of EDM power, a type of energy-saving and chopper high frequency pulse power controlled by Micro Controller Unit is put forward. This power adopts constant-current circuit of low-dropout voltage series to designing the main pulse current topology, and adopts two DC switch powers and the main circuit of Metal Oxide Semiconductor Field Effect Transistor. Its arcing power switch tubes works in the zero current switching state, and its chopper power switch tubes are on in the zero current switching state and off in low-dropout voltage. PWM pulse signal, produced by controlling the MCU, drives power switches by driving circuits, and outputs high-frequency pulse current over 500 kHz on the load. The system of pulse power employs master-slave two level control structure — upper PC and the main MCU control module. As waveform generator, the main MCU realizes pulse width modulation and pulse interval control. Through Universal Asynchronous Receiver Transmitter, communication between master PC and slave MCU can be realized. The designs of power supply circuits of the main circuit, control circuits, drive circuits, and constant circuits are obtained through a number of stimulation experiments and data from board and integrated tests. The experiment and test results indicates that the power completely avoids the loss produced by the limiting resistor and improves the working conditions of components of power switches, and efficiency of the pulse power is greatly improved, so the design targets are basically reached.What can be fully proved is that the pulse power possesses great advantages onsaving energy through processing experiments of experimental prototypes on machine tools and analyses of processing situation. The pulse power has obvious advantage in energy saving and greatly improve the utilization of electric power.