Modelling and optimal controllers design for a stand-alone photovoltaic-diesel generating unit

This paper presents the dynamic modeling and optimal controllers design for a stand-alone photovoltaic-diesel generating unit. To limit the continual variation on load-bus voltage and frequency and to extract the maximum power from the photovoltaic generator, two optimal PI controllers are designed based on state and output feedback techniques. The dynamic behaviour of the closed-loop system following common disturbances such as load changes, insolation variation due to clouds and three phase short circuit is investigated. The simulation results show the capability of the closed-loop system for limiting the load-bus voltage and frequency variations within acceptable levels and extracting the maximum power from the PV generator under insolation variation can be realized.