Design and analysis of a switched-capacitor DC-DC converter with variable conversion ratio

In order to increase the low voltage of renewable energy systems to a relatively high bus voltage for the downstream DC-AC grid-connected inverter, a new DC-DC switched-capacitor converter with the potential of output voltage regulation is proposed. The operational principles, with regard to the specific switching conditions, are provided the relationships for the parameter design and efficiency calculation. The topology makes it possible to integrate the high voltage gain and excellent output regulation that open a huge area of applications and create the possibility of maximum power point tracking (MPPT), which is an important advantage of proposed structure. Moreover, the most important advantages of the proposed structure are continuous input current, variety of the DC voltage source values, and the cost of the converter in comparison with the conventional structures. A comparison with other similar structures is given to show the merits of the proposed topology. Finally, the experimental results are presented to clarify the theory and feasibility of the proposed converter.