| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress the deterioration of power conversion efficiency and to avoid an increase in size, an increase in weight, and a rise in cost of a power circuit board, when an overcurrent protective function is provided for a power circuit in which power factor is improved by a power regeneration system. <P>SOLUTION: A power factor improving circuit 10 of the power regeneration system is inserted into a rectified current route between a rectifier circuit and the primary-side ground. Also, an overcurrent detecting resistor R1 for protecting the circuit from an overcurrent is inserted between the circuit and the primary-side ground. An oscillation and drive circuit 2 detects a load current level based on a voltage V3 across terminals of the resistor R1 and performs overcurrent protecting operation. By this structure it is unnecessary to configure the circuit to detect the load current level at the secondary side. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
