Design and implementation of single phase inverter based on Cuk converter for PV system

In this paper, analysis and hardware implementation of a single phase inverter based on Cuk converter for PV system is presented. The buck-boost characteristic of such a converter promotes flexibility for both grid tied as well as standalone connections where the ac voltage is either higher than or lesser than the dc input voltage. Further Cuk based topologies have the better efficiency and voltage regulation, which is a lacking feature in a basic boost or a buck configuration. The proposed system not only offers continuous input and output current but also controlled voltage over a wider range. Hence this topology can serve as an expedient alternative converter stage for photovoltaic applications. In the proposed bidirectional two-switch Cuk converter, DSPIC30F2010 controller is used for controlling the duty ratio of switching pulses. Also, this controller generates PWM signals for the switches of single phase H-bridge inverter. The hardware results for the developed prototype of a Cuk converter based single phase inverter are presented. The developed scheme can easily be scalable to a much larger rating of the PV system.