The double discontinuous mode operation of a converter: a method for soft switching

This paper describes a way of ensuring soft switching in a converter without using additional components. This method is called double discontinuous mode (DDM). In particular, it permits any free wheeling diode to switch off at zero current, and for transistors to switch on at zero current and to switch off at zero voltage. The method illustrated here refers to a buck, but this concept may be applied to any type of converter, with or without transformer. Various mathematical models of this method are developed, and its characteristics and fields of application highlighted in this paper.