A combined controller for a PV simulator

This paper presents a scheme combining two controllers for a buck-based PV simulator. These two controllers are referred as current mode controller and voltage mode controller. The idea of using two controllers is based on the observation that one controller shows a good performance only in a segment of the iv-characteristic curve where the other controller cannot perform well, and thus, both controllers can be activated in a complementary way. A definition of a new variable is introduced, which provides information on the location of the operation point. This information is used by the proposed strategy to enable the most appropriate control mode. Although each controller is designed following different approaches, both are based on a model representation of the system. Numerical results are presented considering a resistor as the load, which is varied in such a way that the iv-characteristic is swept up and down.