PROJECT TITLE :

Design of Cuk Derived Transformerless Common Grounded PV Micro-inverter in CCM

ABSTRACT:

Solar micro-inverters eliminate the need for a line frequency transformer, but they do so by eliminating system grounding and current leakage. Topologies derived from buck, boost, boost-boost, Zeta, Watkins-Johnson, and C' uk converters have already been used to tackle these issues. Second order input and output filters of the C' uk derived inverters are the most efficient, lightweight and inexpensive in the class. For continuous conduction mode (CCM) operation, this study describes the design and operation of a C'uk-derived common-ground PV micro-inverter (MCI). In both stand-alone and grid-connected modes of operation, the inverter is shown to be compatible with both linear and nonlinear loads. Passive components' optimal design criteria are systematically derived to ensure attenuation of input voltage ripples caused by switching and oscillation of output power at two frequencies. In addition, the design criteria also include considerations for maximising efficiency and reducing the complexity of the system. A 300 VA, 110 V, 50/60 Hz laboratory prototype has been used to test the inverter's performance.