| 摘要 |
This regulated ac-dc power supply circuit comprises a power supply transformer 10 having two sets of secondary windings (20, 21; 52, 54) and a compensating transformer (40) having axciting windings (42, 44) and two compensating windings (22, 24). The compensating windings (22, 24) are connected individually in series circuit with the principal power supply secondary windings (20, 21) to which a full wave rectifier circuit (26, 28) and an electric load (36) are connected. The exciting windings of the compensating supply transformer (40) have ac potential applied thereto from the other secondary windings (52, 54) on the power transformer (10) which also supply dc power by means of another full wave rectifier circuit (46, 48) for compensating control circuitry (60) which has an input circuit connected across the load to sense potential variations thereat and an output for varying the ac supply to the exciting windings inversely of variations in load potential. A differential amplifying circuit (64) is used for determining the load potential variation. The error signal produced at the output of the differential amplifier circuit is applied to a transistor (62) effectively to insert a dc component in inverse feedback relationship into the exciting windings (42, 44) of the compensating transformer (40). As the output potential of the power supply increases, the input potential to the rectifier assembly (46, 48) is decreased, and the converse. The direct current flow path is completed through the load whereby little or no energy is dissipated elsewhere. |
