Systematical method of designing the elements of the Cuk converter

In this paper, a systematical method of designing the elements of Cuk converter is proposed to reach the minimum values of output voltage ripple (OVR) and switching current stress. Applying the physical laws and analyses, the mathematical relations of critical inductances between continuous conduction mode (CCM) and discontinuous conduction mode (DCM) are obtained. In addition, the values of switch peak current (SPC) and OVR are calculated in each of operational modes. Since the values of input voltage and load resistance are variable in real systems, the values of OVR and SPC are investigated in the specific ranges of input voltage and load resistance, and the maximum values of SPC (MSPC) and OVR (MOVR) are obtained. Finally, the minimum values of inductances and capacitors are proposed to reach the minimum values of MSPC, MOVR and filter size. The proposed method can be applied for different kinds of dc/dc converters. The simulation results obtained in PSCAD/EMTDC as well as the experimental results verify the presented theoretical subjects.