Patent ID: 8531150

Claim:
A DCDC converter that has an input filter circuit including an input reactor connected to a DC power supply and an input capacitor and converts a DC voltage of the input capacitor into an arbitrary DC voltage to output the DC voltage, the DCDC converter comprising: a switching circuit with an input end connected to the input filter circuit, the switching circuit including an upper arm side switching element and a lower arm side switching element; a smoothing filter circuit connected to an output end of the switching circuit; and a control unit that feeds back a state amount of the smoothing filter circuit and controls to turn on and off the switching circuit, wherein the control unit includes a damping control unit that calculates, based on a voltage of the input capacitor, a damping operation amount for adjusting the state amount of the smoothing filter circuit by dividing the voltage of the input capacitor by a DC component of the voltage of the input capacitor to thereby calculate a fluctuation rate of the voltage of the input capacitor, wherein the damping operation amount corresponds to the fluctuation rate.