Micro-EDM Pulse Power Supply And Control System Research

With the development of social science and nanotechnology,precision and miniaturization has become one of the most important development directions in modern manufacturing industry,Micro electro mechanical system(MEMS)is regarded as one of the most important technologies in twenty-first Century because of its small size,low energy consumption and high integration,there is a wide range of applications in many precision instruments industry.In the field of micro machining,micro electro discharge machining(EDM)is a non-contact processing,which has the advantages of low processing stress,no burr and high hardness,widely used in aerospace,automotive,Bio Medical Instruments in these industries,it is one of the most important means of machining micro shafts,holes and deep holes,its research and development has been the focus of attention of industry and academia.The main purpose of this paper is to study the micro energy pulse power supply of micro EDM and the study of the discharge control system.Firstly,the research background and significance of micro EDM are briefly reviewed,then this paper introduces the origin,development and current situation of micro EDM technology,the machining mechanism and discharge characteristics of micro EDM also be analyzed.According to the characteristics of micro EDM power supply,a controllable RC pulse power supply topology based on RC discharge is designed,The power supply mainly includes EMI filter module,PWM driver module,data acquisition module,short circuit protection module,upper and lower machine communication module,power supply with MOSFET transistor as high frequency switch control,a small current limiting current is used to obtain high frequency and narrow pulse width voltage to realize micro energy processing.In this paper,the power processing control system is based on FPGA,which is the field programmable gate array and the Nios soft core processor as the control center,the voltage and current signal can be processed and used as a pulse generator,by means of the attenuation circuit and the parallel acquisition of eight bits data,the average voltage of the machining gap and the upper and lower threshold of the processing current are collected to judge the state of the edm,RS232 serialcommunication is used to realize the adjustment of the power supply processing parameters.Micro EDM is a multifunctional microcomputer platform bed three dimensional processing platform,the platform uses Lab VIEW programming block electrode reverse copying,EDM drilling feed back servo control interface,servo control with high precision and fast response characteristics.In this paper,the design of the micro EDM power supply has the characteristics of high frequency,narrow pulse width,small discharge energy,high reliability and good stability.Through block reverse copying of micro rod machining and micro hole machining experiment micro energy performance reliability and processing stability of pulse processing power and check the design,by changing the electrical parameters and processing conditions,the research on micro EDM machining efficiency and machining precision and electrode loss.