Abstract
An advanced analysis method for grid connected PV systems is developed in this research. To investigate the issues which may happen in the clustered PV systems, “Demonstrative research on clustered PV systems" is being conducted from December, 2002, in Oota, Japan. More than 500 residential PV systems will be installed in the demonstrative research area, battery integrated PV systems are developed to avoid the restriction of output power due to the raising of grid voltage. Annual performance of commercial PV systems without battery is analyzed and resulted in around 80% of performance ratio on the average. Over voltage of power distribution line and snow are two major factors of very low performance ratio on daily basis. Effects of batteries are also analyzed, the results indicate that there will be some improvement for the energy loss due to the grid voltage but PCS's efficiency will be around 8% worse than that of the commercial PV systems. It is also found that the non-optimized operation of battery sometimes results in the fully-charged situation during the noontime and maximum reverse power flow may not be minimized in this situation.
