| 摘要 |
1, 008,183. Automatic voltage control systems. SIEMENS-SCHUCKERT WERKE A.G. Nov. 30,1962 [Dec. 1,1961], No. 45552/62. Heading G3R. A system for controlling the electrical output of an electrical retractive control device, such as the output voltage of a direct current generator 1 comprises a comparison unit 6 which derives an error voltage dependent upon the difference between the actual generator output voltage 15,16 and and the desired generator output voltage, a saw tooth generator 8 and a pulse generator 11 which generates a negative going pulse at each zero instant of the saw tooth voltage; the three voltage components shown in figures 3a, 3b, 3c respectively being summed as shown in figure 3d and used to control a bi-stable trigger circuit 9 which is used to control a switching device such as a silicon controlled rectifier 5 in the circuit of the field winching 2 of the generator 1. A second pulse generator 10 is provided to supply quenching pulses for the silicon controlled rectifier 5 and the error signal from the unit 6 is amplified by a unit 7. All the units 6, 7, 8,10,11 are supplied from a square wave oscillator 12. The energy supplied to the field winding 2 is thus controlled by the magnitude of the error signal and the pulse from the pulse generator 11 is used to ensure that the trigger circuit 9 is reset each time the saw tooth voltage returns to its starting value. The amplifying unit 7 comprises a pair of suitably connected transistors whilst the trigger circuit 9 includes a pair of cross connected transistors. The pulse generator 10 controls a second silicon controlled rectifier connected in shunt to the first rectifier 5.
|
