超短脉冲微细电解加工电源及工艺试验

Ultrashort Pulse Power Supply Applied to Micro-ECM and Corresponding Technique Experiments

脉冲电源是实现高精度电解加工的关键技术之一.文中研制了一种用于微细电解加工的超短脉冲——纳秒级脉冲电源,其最小稳定输出脉宽为100 ns,额定电流为1A,占空比和频率均独立可调.该电源采用直流加斩波输出方案,直流部分采用稳压集成块调压.设计的高频信号发生器工作频率范围宽;驱动信号具有陡峭的上升和下降沿,为斩波器提供了良好的驱动保证.斩波主器件采用快速互补功率场效应管,解决了波形失真问题.文中还针对微细电解加工工艺的特点设计了快速保护电路,实现了高精度的微细电解加工.最后,利用该电源样机加工出典型微细零件,验证了电源的有效性.

Pulse power supply is one of the key components of high-accuracy micro-electrochemical machining （ECM）. In this paper, a nanosecond ultrashort pulse power supply for micro-ECM is designed and fabricated, with a minimum stable pulse width of lOOns and a rated current of 1A. In the developed power supply with independent duty-cycle and frequency adjustments, the scheme of DC-plus-chopper is adopted; an integrated block is employed to adjust the DC voltage; and a high-frequency signal generator with wide working frequency is used to provide the chopper with driving waveform possessing nano-second rise time and fall time. A complementary MOSFET is applied to the chopper circuit to avoid the waveform distortion during the machining. Moreover, a fast over-currentprotection circuit is designed according to the characteristics of micro-ECM to ensure the machining accuracy. The effectiveness of the developed power supply is finally verified by the machining experiments of some typical micro parts.