| PECC (Plasma Enhance Electro-chemical Surface Ceramic-Coating) technology has been a hotspot in material science and electrical chemistry now. Because of its trait of"no polluting"and the excellent retia quality, many advanced industrialized countries had done a lot of research on it. The special large power pulse power supply is one of the keys of PECC technology. At present most power supply's output is continuance square waveform pulse in the products, which has some shortages in retia thickness and still engenders burn porcelain phenomenon.To solve above question, This paper brings forward a new kind of power supply whose output current pulses are right-angled triangle and which will be used in industry. The bulk amorphous alloy was chosen as the material of the transform, which enhanced the power of two-transistor flyback converter. This power supply is made up of some parallel units whose topology is two-transistor flyback converter working in discontinuous conduction modes, and the power of every unit is 20kW.PLC is chosen as the key of whole administer strategy and current programmed control as the control scheme. By modulating frequency, width and interval of drive waveform, every triangular pulse's energy can be well controlled to insure the energies are proper whenever. So the retia quality can be improved and the burn porcelain phenomenon will be eliminated. In addition, the over-current, over-voltage, power-down circuit are designed, which ensure the stability and reliability of the system.The equilibrium equations were acquired by establishing the large-signal dc and small-signal dc model, large-signal ac and small-signal ac model of DCM flyback converter in averaged switch model, the stability of the main circuit was researched.The new PECC power supply has been used in the national key industry-PECC trial. It is proved that the power supply works steadily and reliably, and it accords with demands of PECC technics and reaches the practicality.
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