抄録
It has been noted that the voltage of connection points rises according to the reverse power flow when grid-connected photovoltaic systems are concentrated in distribution systems in residential areas. When this happens, the photovoltaic system may control the power generation output to maintain a suitable voltage for the connection point. Designing a demand area power system aiming at free access to a distributed power supply for energy-effective practical use requires a precise understanding of this problem. When analyzing a photovoltaic system mainly connected to a low-voltage system, we looked for a method of analysis in which the high-voltage system and the low-voltage system of a single-phase three-wire system are unified. This report shows use of the indication method between nodes using power flow calculation, for the purpose of developing a technique of analyzing a unified high-voltage system and low-voltage system of a single-phase three-wire system.