Research On Energy-Saving Pulse Generator For EDM Forming Machine

EDM uses controllable electric spark to corrode metals in workpieces,and this method has become a mature processing technology for high power applications.In recent years,EDM technology,which is more and more used in high precision machining and mechanical parts manufacturing,has become an indispensable part of the mechanical manufacturing industry.However,energy shortage,as an major problem facing society today,even restricts the development of EDM machine.Therefore,energy conservation is the development trend of EDM.Pulse generator is an important part of EDM equipment,and its quality determines a series of performance indexes such as quality,speed and stability of EDM.Therefore,the research of new energy-saving pulse generator is of great significance.By the research of energy-saving pulse generator at home and abroad,this paper presents a design scheme of energy-saving pulse generator for forming machine with a new main circuit structure and double closed-loop control strategy of output voltage and current,on the basis of existing energy-saving pulse generator circuits.The main circuit of energy-saving pulse generator for forming machine is divided into two stages.The former DC/DC converter is designed to achieve stable and adjustable output voltage,and the latter sequential processing circuit regulate the discharge pulse width and the pulse interval through the sequential controller to control the gap discharge current finally.Because the pulse generator uses inductances instead of current limited resistances,the energy utilization rate is improved,and the volume of the pulse generator is reduced by using high frequency transformer.The control system of the pulse generator takes TI's TMS320F28035 chip as its core,and designs a core control board,driving circuit board and sampling circuit board.It undertakes the task of generating PWM control signal and pulse width,pulse interval control signal and double closed-loop control strategy of output voltage and current.Modeling,simulation and analysis are realized by using PSIM simulation tool,which proves the feasibility of the system and optimizes the system design.Finally,the correctness and feasibility of the design are verified by making the pulse generator prototype and the actual process tests.