小孔加工电火花脉冲电源实验研究

摘要

For the problems of the low energy utilization of conventional pulse generator,the re-sistors overheating and huge cooling equipments,a kind of EDM pulse generator was presented here-in,which cancelled the current limiting resistors.The pulse generator was made up of a PWM control-ler,a DC/DC converter,a machining pulse sequence generator and so on.It could automatically adj us-ting the output voltages,and the no load voltages,pulse width and pulse interval were adj ustable in a wide range.The bulky frequency transformer was cancelled in the pulse generator.The experimental curves of the electrode wear rate,small holes’ovality and one-side discharge gaps were obtained by the multiple small hole machining experiments.The experimental curves were closely related to the stability of the pulse generator.These data show that the pulse generator has good stability and relia-bility.%针对传统脉冲电源普遍存在的电能利用率低、电阻发热严重、散热设备庞大等问题，提出了一种取消限流电阻的电火花脉冲电源结构。电源由 PWM控制器、DC/DC 变换器、加工脉冲时序发生器等组成。电源本身具有自动调节输出电压的功能，可实现空载击穿电压、脉冲宽度、脉冲间隔独立可调，取消了体积庞大的工频变压器。通过多次小孔加工实验获得了脉冲电源加工过程中电极损耗率、小孔椭圆度以及单边放电间隙等和电源稳定性相关参数的数据曲线，所得数据表明电源具有较好的加工稳定性和可靠性。