Fuji Electric Co., Ltd.

Kazuyuki Yoda

Ryuji Yamada

Qichen Wang

Makoto Yatsu

Hiroshi Takano

Takaharu Ohkanda

Ryuta Nishizuka

A snubber device to be mounted to a terminal of a semiconductor module is provided. The snubber device includes n (n: integer of 1 or greater) parallel charge paths each having a positive-side capacitor, a first diode, and a negative-side capacitor sequentially connected in series between positive-side and negative-side terminals of the semiconductor module, and configured to enable current to flow from the positive-side terminal toward the negative-side terminal; and (n+1) parallel discharge paths each of which having a second diode connected between the negative-side terminal or the negative-side capacitor of an Ncharge path (N: integer within a range of 0&#x2264;N&#x2264;n) of then charge paths and the positive-side capacitor of a (N+1)charge path of the n charge paths or the positive-side terminal, and configured to enable current to flow from the negative-side terminal toward the positive-side terminal via at least one of the negative-side and positive-side capacitors.

Snubber device and power conversion apparatus

A lead acid battery device includes a lead acid battery, a charge control unit to charge the lead acid battery by alternately and repeatedly performing high voltage charging, in which a pulsed high voltage is applied to the lead acid battery, and low voltage charging, in which a low voltage lower than the high voltage is applied to the lead acid battery, and an internal resistance calculation unit to calculate an internal resistance of the lead acid battery based on the voltage difference and the current difference of the lead acid battery between a condition at which the pulsed high voltage is applied and a condition at which the pulsed high voltage is not applied.

Lead acid battery device, control device for lead acid battery, and control method for lead acid battery

With a conventional pulse charging method, a low voltage value for the pulse voltage is set to zero volts. When the low voltage value is low in this manner during charging, there is a problem that the negative pole of a secondary battery deteriorates. Provided is a secondary battery apparatus including a secondary battery and charge/discharge control apparatus that controls charging and discharging of the secondary battery. The charge/discharge control apparatus repeatedly performs, in an alternating manner, high voltage charging of applying a pulsed high voltage to the secondary battery and low voltage charging of applying a low voltage that is higher than 0 V and lower than the high voltage to the secondary battery.

Growing community of inventors

Kobe, Japan

Kazuyuki Yoda