摘要 |
1,021,229. Converting. BROWN, BOVERI & CO. Ltd. Dec. 12, 1962 [Dec. 14, 1961], No. 46880/62. Heading H2F. A rectifying arrangement comprises several groups of uncontrolled rectifiers in bridge connection and one group of controlled rectifiers in bridge connection with switches arranged to connect in series a desired number of the uncontrolled groups. In the Figure, a traction motor 9 is supplied from rectifiers connected to secondary windings 1, 2, 3, 4 of a transformer. Only the bridge'connected to secondary winding 1 is controlled, either two of four of its elements being controlled elements. With the switches arranged so that only this bridge is connected to the motor, the circuit may be used as an inverter. Inductors 7 and 8 are connected as shown. If the controlled bridge has only two controlled elements, then the controlled and ' uncontrolled elements may be connected to different tappings on the winding 1. The Specification describes the sequence of switching required to increase or decrease the number of groups in series. |