Kawasaki Jukogyo Kabushiki Kaisha

Mikihiko Kataoka

Masato Hayashi

Soichiro Bando

Tatsuya Ohno

Takayuki Tokushige

Tomoyuki Komai

A power storage system supplies electric power to a load, and includes: a secondary battery; a capacitor connected in parallel to the secondary battery; and a controller performing control to prioritize charging and discharging of the capacitor over charging and discharging of the secondary battery.

Power storage system and method of controlling the same

In a power storage system, a bidirectional DC-DC converter is set into mode for charging a secondary battery with electricity when a first state of charge (SOC) of the secondary battery is larger than a minimum value of the first SOC, and a second SOC of the capacitor is smaller than a maximum value of the second SOC, and the converter is set into mode for discharging electricity from the secondary battery when the first SOC is smaller than a maximum value of the first SOC, and the second SOC is larger than a minimum value of the second SOC. Based on an internal resistance of the secondary battery, the second SOC, a voltage of a direct current link in case of no load connected to DC link, and an error in a current on a direct current link side, a conduction ratio (D) of the converter is calculated.

Growing community of inventors

Kobe, Japan

Mikihiko Kataoka