Weighted Efficiency Optimization of Flyback Microinverter Under Improved Boundary Conduction Mode (i-BCM)

The flyback topology is proven to be a very strong candidate solution for use in ac-PV module applications. Operation in the boundary condition mode (BCM) provides high power density, while maintaining the characteristics of a current source inverter. In this paper, a design methodology is presented, that maximizes the weighted efficiency of the converter through an optimization algorithm. The inverter operation is investigated and the behavior under the improved BCM is documented by analytical equations followed by the power loss calculations for each component. This enables to accurately define the relation between the design parameters and the efficiency of the implemented converter and so, an optimization algorithm is established, that takes into consideration the design specifications and constraints. The proposed methodology is also verified with an experimental prototype.