【作者】 王尧锋；

【导师】 张永俊；

【作者基本信息】 广东工业大学 ， 机械制造及其自动化， 2006， 硕士

【摘要】 电解加工(Electrochemical Machining ECM)技术在加工各种难切削金属材料时,具有传统加工方法无法比拟的优点。这些优点使其广泛应用于国防、航空航天和各个民用领域,成为了机械制造业中不可缺少的组成部分。但电解加工精度还不够高,逐渐难以满足高科技产品对其精度越来越高的要求。科技的发展也推动了电解加工技术的进步,研究实践表明,用高频脉冲电源电解加工能有效地提高加工精度和表面质量。而且频率越高,脉宽越窄,其加工效果就越好。该技术有望促使电解加工进入微精加工领域,而高频脉冲电解电源的研究是推动电解加工技术向前发展的关键之一。 本文针对相关项目的内容,研制了频率更高的高频脉冲电源样机。结合电解加工的需要,并综合考虑了电源效率、体积重量等问题,本电源样机采用全桥变换器加斩波脉冲输出方案。变换器调压方案省略了铜、铁损耗大的工频变压器,提高了电源的效率,减小了电源的体积和重量,而且调压精度较高。斩波输出方案又使电路简单,降低了电源的成本。 电源的变换器部分,用脉宽调制法对电压进行闭环控制,能够为斩波部分提供一个稳定可调的直流电压。变换器部分主要解决了高频磁芯变压器的波形畸变问题,成功设计制造出输出波形良好,工作稳定的高频功率变压器。 电源的斩波部分针对高频较大电流的脉冲输出,较好地解决了驱动电路快速性问题,功率场效应管的并联均流问题,和脉冲关断瞬间的电压过冲问题。并针对电解加工的特点设计了快速保护电路。 结合相关项目的内容,用电源样机进行了电解机械复合抛光的工艺试验,试验结果验证了高频脉冲电源有利于提高加工的表面质量。用电源样机进行微细孔电解加工试验,结果也验证了脉冲频率的提高,脉宽的缩小有利于提高加工精度。更多还原

【Abstract】 Electrochemical Machining (ECM) has many excellences than conventional machining in machining hard cutting material. These bring its broad application to national defense, aviation, and many civil fields. And ECM has become an indispensable part in machine manufacturing. But its machining precision is not so high enough to reach the higher and higher requirement of the high-tech products. The development of science and technology also improve the ECM technique. Many research and applications show that, by using pulse power supply the ECM precision and surface quality can be improved effectively. And the effect will be better with higher frequency and shorter pulses. This technique is expectant to lead ECM into the micro and precision machining fields. And the key is high frequency pulse power supply.According to relative project, this dissertation developed an ECM pulse power supply with relatively higher frequency. The power supply model adopts the scheme of converter-plus-chopper. This scheme can reduce the bulk and weight of the power supply, and can improve its efficiency. Moreover the voltage regulation is more precise.The converter applies PWM (Pulse Width Modulation) technique to regulate the voltage. A tailor-made transformer and snubber circuit have been design to reduce the distortion of output waveform.In the part of chopper, a fast drive circuit, a snubber of over-voltage-protection and a fast over-current-protection circuit have been design. And the parallel operation of MOSFET was achieved effectively.An electrochemical mechanical polishing test and a micro-holes’ machining test was carried out. The test result validate that high frequency pulse power supply can improve the surface quality precision of the workpiece.更多还原