  Cuk and SEPIC are some of the important DC-DC converters used for charging
batteries. In this paper, a generalized circuit averaging technique is employed
for Cuk and SEPIC converters. The derived equations are used to obtain the
frequency response of open loop transfer function. The ratio of perturbed
output voltage to duty cycle ($G_{vd}$) is simulated using LTSpice software
package. The derived averaged models of the converters aids in faster and
simpler simulation. The behavior of the converters in CCM and DCM was also
simulated. The derived expressions can be generalized to power converters with
two switches.
