Research Of Micro-Energy Pulse Power Module For Micro-EDM

Micro-EDM (Micro Electricl Discharge Maching) is an important technology in the field of micro-machining, for its advantage of non-contact, non-macroscopic cutting force, etc. micro-EDM technology has been attention in many countries. While the micro- energy pulse power is one of key technologies of micro-EDM system, its performance has a direct impact on technics indicators of micro-EDM. So research of its key technology, command the realization principle and design method of micro-energy pulse power, have important significance for research of micro-energy pulse supply and development of micro-EDM system.This paper has analysed the basic principles of micro-EDM based on reading lots of relevant information of at home and abroad. Through analyzing the influence of a single pulse energy and parasitic capacitance on the process surface quality, find that high peak current and short pulse width are propitious to improve processing quality. This paper has also researched the power switching MOSFET drive technology and the average voltage detection technology of micro-energy pulse power, and used average voltage detection circuit to simulate and analyse.The designed micro-energy pulse power of mirco-EDM system mainly include high- frequency pulse signal generation circuit, driver amplifier, power conversion circuit, detection circuit and the main power circuit. The core of this pulse power is the high-frequency pulse signal generation circuit. It uses the 80C51 single chip P89LVRD2 and complex programmable logic device (CPLD) EPM570T1003N to produce pulses. It can set the pulse signal parameters on line, and can continuously adjust the pulse width between 50ns and 5μs. The design concept of this pulse power is that use high-frequency pulse signal which generated by pulse signal generation circuit through driver amplifier, to control power switch MOSFET on and off, then get the required discharge pulses which accord with machining gap. And through dealing with the discharge state detection signal which feed back from detection circuit in time to attain the best processing discharge pulses.Finally, it debugged and tested the hardware and software of the designed micro-energy pulse power system. And through testing the pulse waveforms with pulse width 1us, 0.2us, 0.1us and 0.05us, found that its stability is better. The tested results verify the designed micro-energy pulse power can meet the micro-EDM requirements. However, the pulse waveforms exists a little delay, so it should be studied in further and verified in actual processing conditions.