Introduction to Electrical Power and Power Electronics

340 Introduction to Electrical Power and Power Electronics

The relations 13.5 and 13.6 between the output and input voltages and currents

(all dc) are analogous to the ac transformer relations. The duty ratio D in the dc–dc

converter effectively works like the turn ratio in an ac transformer. This converter is

therefore often incorrectly called the dc transformer, although it works on a funda-

mentally different principle than the ac transformer as we know it.

We have assumed in the above analysis that the buck converter is operating in the

continuous conduction mode, which requires a minimum output current. If I

out

< 1/2

ΔI

L

, the load current ...