配電線スリム化を目的としたダイナミックレーティング適用時の蓄電池設備容量評価

Abstract

Because of a large number of facilities in distribution lines, the rationalization of power distribution equipment is an important issue. In recent years, photovoltaic power generation system (PV) has become increasingly interconnected, so the use of distributed power sources and storage battery to streamline facilities is also being studied. However, large capacity of the storage battery is required to reduce power flow in distribution lines using only the storage battery. Dynamic rating (DR), on the other hand, dynamically changes the current capacity of transmission lines and transformers according to weather conditions and other factors. In this study, the necessary capacity of the storage battery is evaluated by distribution lines according to DR. Furthermore, considering transitional characteristics of the wire temperature about current that it takes several minutes to change after varying current can increase the allowable current capacity in distribution lines based on DR. Since downsizing distribution lines to rationalize distribution facilities increases the impedance in distribution system, there is a problem that the voltage fluctuation becomes large. Therefore, this paper proposes a method for calculating the necessary capacity of storage battery according to DR considering transient temperature change and voltage fluctuations in the distribution system. Then, the necessary capacity of the storage battery is evaluated through numerical simulations based on actual annual data.