抄録
This article introduces a power compensator using Lithium-ion batteries for DC train system and a basic technology of a lifetime estimation of the battery during its operation. The technologies developed for the compensator are applicable to a large-scale storage for distribution system. The battery model used for the lifetime estimation is also applicable to a State of Charge (SOC) measurement. Because the model of the internal impedance is able to represent its frequency characteristic having close relation to its life, the model expresses transient response and lifetime of the battery. No extra charging/discharging circuit and no removal of the battery from equipment are required because the modelling method using voltage and current waveforms during its operation. The accuracy of the proposed modelling method is confirmed by a laboratory test and a running test of an electric bike.