Development of Photovoltaic System for Optical Network Unit

In information lines, copper wire cables have been replaced by optical fiber cables that cannot supply power to the optical network unit (ONU). Thus, in the case of disasters, communication function paralyses may take place. Therefore, the reliability of power supply to the ONU has become important in recent years. With this background, we have developed a PV system for the ONU. In the process of development, we have proposed a novel estimation method for PV systems, that enables us to easily grasp the relationship between the instruments in the system from an overall view by regarding the instruments as the black boxes and paying attentions only to Ehe energy flows. The proposed method is useful in determining the suitable parameter arrangement of the PV system. Utilizing the method, we developed lOW order PV systems and carried out the experimental operation for one year. The experimental results showed enough system performances to meet not only the design requirement but also the spatial constraint.