| 摘要 |
A transformer (2) steps down an input AC power, and supplies the AC power to a converter (3). The primary voltage of the transformer (2) detected by a voltage detector (8) is supplied to a converter controller (4) and a frequency detector (6) via a BPF (5). The converter controller (4) controls the converter (3) such that a power factor is equal to or greater than a predetermined value based on the primary voltage, and the converter (3) converts the AC power into DC power. The frequency detector (6) detects the frequency of the primary voltage based on an interval between time points at which the primary voltage via the BPF (5) exceeds a threshold. A filter adjuster (7) calculates a filter characteristic with the detected frequency as a center frequency of the BPF (5), and adjusts the BPF (5) based on the filter characteristic. |
