A novel microcontroller for grid-connected photovoltaic systems

The purpose of this paper is to develop a novel microcontroller for grid-connected photovoltaic (PV) systems. As a prototype model, a 100-W-class module-integrated converter composed of the proposed controller and a flyback inverter has been built and tested. The prototype model is designed to satisfy the Japanese grid-connection guideline. Basic functions as those of a grid-connected PV inverter, such as the maximum-power-point tracking and the anti-islanding protection, have been confirmed in the experiments, using a distribution network simulator located in a laboratory. This paper presents the description of the controller and the experimental. results. A microcontroller has been developed with a 50-MHz-class microcomputer and simple interfaces. By revising the program, the proposed controller can be applied to various types of PV systems or grid-connected equipment.