A new snubber circuit for diode-clamped four-level inverter and converter

This paper proposes a new snubber circuit for a 4-level inverter and converter. The snubber circuit makes use of an Undeland snubber and McMurray efficient snubber as its basic snubber unit, and can be regarded as a generalized combined Undeland and McMurray efficient snubber. The proposed snubber keeps such good features as fewer number of components, improved efficiency due to low snubber loss, capability of clamping overvoltage across main switching devices, and no unbalance problem of blocking voltage.