Hybrid phase arm power module with nonlinear resonant tank

A soft switching concept for a phase arm module, suitable for switching frequencies in the ultrasonic range, is introduced. Apart from series smoothing capacitors on the supply the only additional components to the switches and diodes of the phase arm is a parallel nonlinear resonant tank. A major feature is that the installed switching power of the semiconductors is close to 1 p.u. pulse-width modulation (PWM), as obtained through control of the saturation depth of the saturating inductor.<
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