Todays, DC to DC power converters, known as DC choppers, are widely employed in a variety of applications such as power supplies, spacecraft power systems, hybrid vehicles and DC motor drives. Among these converters, Buck, Boost, Buck-Boost, Cuk and Sepic have found the most industrial applications. This paper determines the small signal averaged state-space models of these converters and provides an excellent understanding of the frequency domain behaviour and a tool to design and analyse the feedback control loops for them. The theoretical results are validated by simulations in PSIM software.