摘要 |
A power supply device includes: a rectifier having a full-wave rectification circuit whose low side elements are made of MOSFETs; an electrical load supplied with DC power from the rectifier; and a control circuit having a load voltage detector and an AC voltage detector for detecting an input terminal voltage from a permanent-magnet generator; wherein when a terminal voltage across the electrical load is lower than a predetermined value, the control circuit operates the rectifier in full-wave rectification mode, whereas when the terminal voltage across the electrical load is higher than the predetermined value, the control circuit short-circuits input terminals of the permanent-magnet generator with each other, and when power for driving the control circuit is not secured, the control circuit retains the full-wave rectification mode even if the terminal voltage across the electrical load is higher than the predetermined value. |