Capacitor device

摘要

A capacitor device includes a capacitor unit, a voltage-dividing circuit for outputting a divided voltage obtained by dividing a voltage of the capacitor unit, and a comparator circuit. The comparator circuit causes the charge circuit to operate such that the voltage of the capacitor unit reaches a full-charge voltage. The voltage-dividing circuit includes a semiconductor switching element, and outputs a divided voltage. A control circuit is operable to determine the full-charge voltage to be a high-temperature full-charge voltage by turning off the first semiconductor switching element when a temperature at the capacitor unit exceeds a reference temperature. The control circuit is operable to determine the full-charge voltage to be a low-temperature full-charge voltage that is higher than the high-temperature full-charge voltage by turning on the first semiconductor switching element when the detected temperature is not higher than the reference temperature.

主权项

1. A capacitor device comprising:
a capacitor unit; a charge circuit for charging the capacitor unit, the charge circuit being configured to be connected to a main power supply; a temperature detector for detecting a temperature of the capacitor unit or a temperature around the capacitor unit; a voltage-dividing circuit for outputting a divided voltage obtained by dividing a voltage of the capacitor unit; a reference voltage circuit for outputting a reference voltage that is a constant voltage; a comparator circuit comparing the divided voltage with the reference voltage so as to cause the charge circuit to operate such that the voltage of the capacitor unit reaches a full-charge voltage; and a control circuit for determining the full-charge voltage, wherein the voltage-dividing circuit including:
a first resistor and a second resistor connected in series to the first resistor at a node; anda first variable resistor unit connected in parallel to the first resistor, the first variable resistor unit including a third resistor and a first semiconductor switching element connected in series to the third resistor, wherein the voltage-dividing circuit outputs the divided voltage from the node, and wherein the control circuit is operable to:
determine the full-charge voltage to be a predetermined high-temperature full-charge voltage by turning off the first semiconductor switching element when the detected temperature exceeds a reference temperature; anddetermine the full-charge voltage to be a predetermined low-temperature full-charge voltage that is higher than the high-temperature full-charge voltage by turning on the first semiconductor switching element when the detected temperature is not higher than the reference temperature.