Fujitsu Corporation

Yoshinobu Matsui

Tomotake Sasaki

Yoshiyasu Nakashima

Yu Yonezawa

Hisato Hosoyama

A power supply apparatus includes: an inductor to which an input voltage is applied; a switching element that switches a current flowing to the inductor on and off so as to cause an induced voltage to be generated; an electrolytic capacitor that smoothes the induced voltage and outputs the voltage to a load; and a control circuit that controls the switching element, wherein the control circuit outputs a second switching control signal obtained by superimposing a degradation detection-purpose signal for detecting degradation of the electrolytic capacitor on a first control signal, detects an output voltage output by switching performed by the switching element controlled by the second control signal, and estimates the degradation of the electrolytic capacitor by using the output voltage detected, a duty cycle of the first control signal, and a frequency component of the degradation detection-purpose signal contained in the output voltage detected.

Power supply apparatus, control apparatus, and program therefor

A PFC circuit generates substantially sinusoidal current that is in-phase with AC input voltage to compensate for a power factor. A DC-DC converter converts the voltage of a signal outputted from the PFC circuit to determined voltage. A current change detection section detects an amount of change in current outputted from the DC-DC converter, compares the detected amount of change in current with a threshold set in advance, and if the detected amount of change in current is larger than the threshold, outputs a gain switching signal for raising the gain of voltage outputted from the PFC circuit. The current change detection section outputs a voltage control signal for raising the voltage outputted from the PFC circuit to a determined value. A voltage setting section sets the voltage outputted from the PFC circuit to the determined value on the basis of the voltage control signal.

Growing community of inventors

Kawasaki, Japan

Yoshinobu Matsui