Research On Micro Energy And Controllable Pulse Power Supply For MWEDM

With the development of modern manufacturing technology, MWEDM (micro wire electrical discharge machining) has been recognized for various advantages in manufacturing industry. Pulse generator, as one of the critical parts of MWEDM system, takes an important role in machining. Compared to conventional WEDM pulse generator, MWEDM pulse generator requires higher character in the style of energy controlling. Hence, the development of micro-energy and controllable WEDM pulse generator has positive significance to the improvement of the art of WEDM.First,this paper introduces the recent state of the art of MWEDM pulse generator all over the world, and on the basis of expatiation on the principles and characteristics of traditional EDM pulse generator and some typical MWEDM pulse generators, analyzes factors that affect the control of discharge energy, and also discusses methods to reduce the influence caused by stray capacitance in theory.To fulfill the demand for pulse generator of MWEDM, this paper advances the idea that circularly superposing pulse signal and eliminate leaking current with new topology, and also accomplish the hardware design of important module such as the current controlling and circularly superposing module, the gap voltage detecting module, the gap voltage comparing module and so on.The control system mainly consists of communication and voltage detecting module and pulse generating and current controlling module base on CPLD. This paper designs the program of pulse generating and current controlling module with assemble language and designs the program of CPLD by using both VHDL language and graphic editor, and also do the work of emulation.We use this pulse generator to do machining experiments, and analyze output waves of important modules. And also do efficiency experiments under different conditions, which illustrates this generator meet the needs of MWEDM.