| 摘要 |
<p>PURPOSE:To obtain a DC signal having small ripple without increasing a time constant of a filter by providing only one expensive transformer for an instrument even when n-phase AC voltages are detected. CONSTITUTION:An AC voltage detector (11-15) for automatic voltage regulators (1-15) step down a terminal voltage of an AC generator AG by one transformer 11 for an instrument, an auxiliary transformer 12, convert its single-phase AC signal into three-phase AC voltages by a single-phase/three-phase converter 13, three-phase full-wave rectify it by a three-phase full-wave rectifier 14' to obtain a DC signal of the AC voltage in which three-phase full-wave rectified waves are removed by a filter 15. Since the full-wave rectified wave has smaller ripple than that of the single-phase full-wave rectified wave, a DC signal having small ripple can be obtained even if the time constant of the filter 15 is not increased. Since the time constant of the filter can be reduced, quick response of a control system can be improved.</p> |
