In this paper, a control scheme is proposed for a three-phase isolated photovoltaic (PV)-diesel system without an energy storage element. The scheme aims to: track maximum power from the PV array, regulate the load voltage, compensate the load unbalance viewed by the diesel generator, and to control the diesel engine speed. The first three tasks are achieved by controlling the PWM inverter interfacing the PV array to the system. The fourth is realized by a modified fuzzy logic controller of the diesel engine. The obstacles encountered on operating the system under certain probable loading conditions are addressed. Two strategies are proposed to adapt the control scheme to accommodate all loading scenarios maintaining excellent technical and economic performance. The system operation is investigated under a variety of conditions to prove the aptness of the proposed techniques.