A Local Energy System including Solarcells

A local energy system including many solarcells and a single secondary battery is presented. These energy sources are connected to an ac bus line through inverters. The bus line supplies ac power to many loads. In this system, the output voltage of each solarcell is always kept constant by each interface in order to derive the maximum power from each solrarcell even when the ligtht strength from the sun changes. Adjustment of power between sources and loads is accomplished by the secondary battery. Circuit configurations and a stability criterion of this automatic interconnection are presented.