| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a harmonic restraint power supply, suppressing a harmonic wave, and a control circuit therefor.SOLUTION: In a harmonic restraint power supply 1 and a control circuit 30 according to a first embodiment, a first capacitance reduction circuit section in the control circuit 30 reduces the capacitance of an input capacitor 20, at a light load in which the output power of a step-up chopper circuit 10 is predetermined load power or lower, so that harmonic distortion can be suppressed at the light load. Also, in a harmonic restraint power supply 1 and a control circuit 30 according to a second embodiment, an input phase detection unit of the control circuit 30 detects the input voltage phase of the step-up chopper circuit 10. Based on the input phase information of the input voltage phase detected by the input phase detection unit, a second capacitance reduction circuit section in the control circuit 30 reduces the capacitance of the input capacitor 20, so that harmonic distortion can appropriately be suppressed over a wide range of load region.</p> |
