Study On The Parallel Inverter Control Technology Of Solid State Super-sonic Frequency Power Supply

Control strategy for the parallel-resonance super-frequency induction heating power supply is designed in this paper. The load character and control object for a parallel inverter is analyzed, the conclusion that series and parallel resonant circuit are two antithetic circuits is pointed out, this provides a theoretical guide to the control circuit design for these two inverters. Through the analysis of different operating states, it is pointed out that a capacitive quasi-resonant state is a safe and efficient working condition for a parallel inverter. A zero-voltage starting method is brought forward which switch the starting from separate exciting to self-exciting successfully; PLL(Phase Lock Loop) technology is employed to realize the frequency tracing and constant phase angle control; IGBT driving and protective circuit suitable for parallel inverter is developed, which successfully solve the problem of time compensating and overlapping regulation for the driving signals; A novel and practical over-voltage protective method for parallel inverters is presented which effectively avoid the possible over-voltage destroy to the inverter. Xu Haiwen (Power Electronics and Electric Driving) Directed by Senior Engineer Peng Yonglong...