| 摘要 |
PURPOSE:To continuously vary the output of a switching power source by controlling the chopper operating level in a range of low output power and in the vicinity of the rated output and controlling the duty level in a range of high output power, and reducing harmonic components. CONSTITUTION:The DC power source 12 is chopper controlled by the switching element 14 to supply energy to a reactor 13. Chopper operating period t1-t2 is varied with the duty fixed in a range of low output voltage and in the vicinity of the rated output, and the duty levels I, II, III are altered in a range of higher output power than a predetermined value, and a control circuit 100 for producing a control signal for fixing the chopper operating period is provided. The output can be continuously varied by combining the two types of controls to restrict the harmonic components with less loss. |
