Background: Traditional thyristor-based three-phase soft starters of induction motor often
suffer from high starting current and heavy harmonics. Moreover, both the trigger pulse generation
and driving circuit design are usually complicated.
Methods: To address these issues, we propose a novel soft starter structure using fully controlled
IGBTs in this paper. Compared to approaches of traditional design, this structure only uses twophase
as the input, and each phase is controlled by a power module that is composed of one IGBT
and four diodes.
Results: Consequently, both driving circuit and control design are greatly simplified due to the requirement
of fewer controlled power semiconductor switches, which leads to the reduction of the
Conclusion: Both Matlab/Simulink simulation results and experimental results on a prototype
demonstrate that the proposed soft starter can achieve better performances than traditional thyristorbased
soft starters for Starting Current (RMS) and harmonics.