| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic voltage regulator which constitutes a tap switching device using an AC thyristor switch of an air specification so as to reduce a cost and enhances easiness of the maintenance.SOLUTION: Tap changeover devices 4u to 4w are constituted by using a three phase alternating current thyristor switch of an air-specification as tap changeover switches A, B, C, T1, T2, and S. The three phase alternating current thyristor switch includes: a main circuit switch for three phases composed of a thyristor; a power supply portion for control for rectifying the three phase voltage taken from one end of the main circuit switch and for outputting a direct current voltage; and a control portion for giving a trigger signal to the thyristor with the output voltage of the power supply for control used as a power supply voltage. The three phase line voltage of all the energization taps connected with the three phase alternating current thyristor is maintained at the minimum operation guarantee voltage or above which is necessary for the three phase alternating current thyristor switch to stably operate by providing a tap te dedicated for grounding other than current-carrying taps ta to td for a low-voltage winding of regulating transformers 3u to 3w. |
