Patent ID: 6674657
Filing Date: 2004-01-06
Classification: H02M

Abstract:
An overvoltage-protective device for a power system that has an AC/DC converter and a DC/DC converter to which output power of the AC/DC converter is inputted as its input power comprising:an overvoltage detecting circuit for detecting overvoltage state of output power of the DC/DC converter; an alarm circuit for outputting an alarm signal as a detection result obtained by the overvoltage detecting circuit; a change circuit consisting of a first output-current-supply-capability setting circuit for setting output-power characteristics of the AC/DC converter to first output-current-supply-capability based on the alarm signal and a second output-current-supply-capability setting circuit for setting output-power characteristics of the AC/DC converter to second output-current-supply-capability based on the alarm signal; and a switching circuit for switching connections between the first output-current-supply-capability setting circuit and the second output-current-supply-capability setting circuit.