| 摘要 |
1,144,586. Converting; synchronous generators with D.C. excitation. ALLMŠNNA SVENSKA ELEKTRISKA A.B. 28 June, 1966 [29 June, 1965], No. 28924/66. Headings H2A and H2F. A thyristor converter 3 is normally controlled by a control pulse generator 13, but if the voltage of the A.C. system drops below a certain value this is detected by a device 20 and a continuous firing signal is applied to the control electrodes of all the thyristors. The field winding 2 of a generator G is compound excited from transformers 7, 10 through the uncontrolled rectifier 4 which is connected in series with the converter 3 which may invert or rectify as required. Normally, the converter 3 is controlled by the pulse generator 13 in accordance with the voltage and current monitored at 15 and 16 respectively. The generator voltage rectified at 17 charges a storage battery 19 through a controller 18 and is also fed to the detector 20, which connects the battery 19 to an oscillator 21 and rectifiers 26, 27, 28 when the generator voltage falls. The invention prevents overloading of one thyristor due to commutation failure when the generator is short circuited. |
