Guidelines for evaluating grid connected PV system topologies

Several grid connected photovoltaic system topologies are used in existing installations. This paper proposes evaluation criteria for comparing and choosing topologies compatible with the user´s demands. After presenting an overview of current architectures used in grid connected systems, five key points for comparison based on topology upgradeability, performance under shaded conditions, degraded mode operation, investment costs and ancillary service participation are discussed. The proposed method can be adapted to the user´s particular needs and expectations of the photovoltaic plant.