| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To increase the efficiency and elevate the reliability of an alternator for a vehicle. <P>SOLUTION: When this charger goes to an overvoltage state (Vr1 (Vmax)<V 1) where high voltage is applied to a rectification output terminal 502, this transmits it to power MOSFET drive circuits 16a-16c and 26a-26c by a wiring F1, consequently the drive circuit drives power MOSFETs 21a-21c and 11a-11c in reverse phases from normal states. That is, when Vas-Vcs becomes positive (a current flows from a generator 200 to a bridge circuit), a lower arm transistor connected to AC output terminals 506-508 is turned on. At this time, the upper arm transistor of a reverse arm for forming a counterpart to it, is turned off to reduce the current from a generator. Moreover, when Vas, Vbs, and Vcs become negative (a current flows from the bridge circuit to the generator), the transistor for the upper arm is turned on. At this time, the lower arm transistor of the reverse arm to form a counterpart to it is turned off. <P>COPYRIGHT: (C)2003,JPO</p> |
