Development Of Phase Shift Inverting Power Of The Plasma Spray Welding Equipment

This project based on a great deal of characteristics of plasma arc spray welding technology , for example , the high temperature of plasma arc , the low diluting rate of welding layer and the widely range of welding material etc., connects the advanced inverter technology with the new power device- IGBT, adopts the latest phase shifting of PWM soft switch control idea , finally, have developed this phase shifting type of inverter power system working on plasma arc spray welding equipment.Because of its reliability of dynamic and static characteristic and energy-conservation, inverter technology is superseding the traditional power step by step. And it develops the directions of high frequency and high-power gradually. The first chapter expounds the basis principle and classification of the inverter technology, and reviews the domestic and international current development situation, points out high frequency, high capacity and intelligentized is their development trends in the future. While some disadvantages are existed in actual spray welding inverter power system , for example , the heavy stress on main power switch, big loss and low dependability etc. To these questions, this text has proposed solving these problems by the soft switch control technology of phase shifting. Then chapter two reviews briefly the evolution of the technology of the soft switch, points out that it is the technology of phase shifting control soft switch that is the technological development trend of the soft switch at present .And two kinds of topological soft switch circuit about phase shifting and controlling are introduced in detail, who are zero voltage (ZVS) and zero voltage zero electric current (ZVZCS). The control scheme this text used is FB ZVZCS PWM, and has been carried on systematic theory analysis to its operation principle, microcosmic varying course in emphases.