Power converter and a vehicle power supply device including the same

In the DC / DC converter for performing zero voltage switching, the first inverter of the primary side of the transformer (8) (15), a second MOSFET (5a, 5b) to the capacitor (6a, 6b) are connected in parallel, inductor (7) is connected to the AC output line. Control circuit (30) is a region current (i) exceeds a predetermined value, and controls the inverter section (15) using a PWM control of the dead time (td) fixed current (i) is equal to or less than a predetermined value the low load region, switching the PFM control, and reduce the frequency so that the dead time (td) is longer with decreasing current (i) is retained without changing the duty ratio.