Development Of High Frequency Pulse Power Supply For ECM And Technical Test

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.