The origin of converters

In the “The Origin of Species”, Charles Darwin stated that organic beings are surviving through evolution, struggling for existence and natural selection [1]. In the “What Is Life?”, Erwin Schrödinger stated that deoxyribonucleic acid (DNA) is the essential element of genetic processes and heredity [2] which implies that we were a family long long time ago. Converters in different configurations are also evolved or derived from certain elements with special principles and they are belonged to families. This paper narrates the philosophy of power transfer first, and then identifies the principle of power converter evolution. Based on the philosophy and principle, we can understand the origin of converters. In this paper, the duality of converters, converter graft scheme, and converter layer scheme are reviewed, and they are applied to derive the PWM converters from the newly developed buck and boost converters based on the resonance philosophy. The PWM converters include buck family: buck, buck-boost, buck-boost-buck (Zeta), and boost family: boost, boost-buck (Cuk), boost-buck-boost (SEPIC). Moreover, the only six PWM converters can be double confirmed. This study provides readers an overall picture of PWM converter evolution and derivation.