High-power Micro-arc Oxidation Power Supply

The microarc-oxidation is a new method of surface treatment, it needs a high voltage pulse power, and the pulse amplitude, frequency, duty ratio can all be regulated continuously in a certain range. Microarc-oxidation coatings on surface can combine with substrate commendably, and it's rigidity, wear resisting property , corrosion proof , heatproof and shock resistance is very good, the film's electrical insulation is well and breakdown voltage is high. In the field of surface treatment of materials, The microarc-oxidation is becoming hotspot of reserch. Zhejiang university and a company cooperate to develop High Power MAO Power Source with bipolar-asymmetrical output with a . Based on the demand of the program and practical application, this paper designs a High Power MAO Power Source made use of 80c196MC and give the process of its development.The microarc-oxidation is described firstly,and then,according to the characteristi c of microarc-oxidation,the request of design of supply is provided. Then, we disscussed the desigh of the main circuit of MAO Power Source. In this chapter, we analyze the principle of MAO Power Source, and particularly introduce silicon controlled rectifier and Chopper topology, then confirm the main circuit which accord with the request of the copartner. In the next chapter, desigh of the control circuit of the MAO Power Source is introduced. The software system is designed in the third chapter. And 80C196MC, driver of IGBT is introduced as well. The driver of IGBT is the key point of the chapter, for it is very important to make sure the main circuit run smoothly. In many cases of application of high power, driver is not only control the IGBT, but also provide some protect. Afterwards, In the next chapter, for one thing, the dissertation analyses the protection circuit of MAO Power Source. The component of the circuit can be destroyed in many cases when the circuit is running, so we should add some protection circuits according to these cases. In the fifth chapter, the important waveforms of the circuit are showed. Finally, a simple summarization and expectation about the dissertation is made.