| 摘要 |
PURPOSE: To make the control simpler and more reliable and reduce the effect of the dispersion of parts by controlling in a predetermined section both negative and positive saturation characteristics of a current transformer and by providing OFF sections between mutual switching by controlling the feedback output. CONSTITUTION: When a base current IB is supplied, switching means 11a is turned on and, after the elapse of a predetermined time, an auxiliary switch 13c is turned on. At the same time, a current transformer 12a is saturated magnetically, an induced voltage of secondary winding 12a2 becomes zero instantaneously, and switching means 11a is forcibly turned off. Since no base current flows to switching means 11b while the auxiliary switch 13c is ON, the auxiliary switch 13c turns off again, and switching means 11b turns on after the base current flows. In this way, an OFF section where both means can be off simultaneously is created between alternate switching of the switching means 11a and 11b and therefore the switching loss and the occurrence of noise can be reduced. |
