| 摘要 |
1,122,556. Control of D.C. motors. ETABS. BRISSONNEAU ET LOTZ. 15 March, 1967 [14 April, 1966], No. 12081/67. Heading H2J. In an electrically propelled vehicle, wheel slip is detected by comparison of the current taken by each motor in a pair and correction effected by strengthening the field of the slipping motor. The motor fields 8a, 8b are separately excited by a closed loop system in which the actual field current, measured at 13a, 13b, is compared with a reference value UIe, and unbalance between the motor currents produces a signal from the appropriate comparator 2a or 2b which is differentiated at 3a, 3b and added to the field reference value. As shown, the fields are energized from a separate A.C. source and control is effected by thyristors or thyratrons 11a 11b, but in an alternative arrangement a D.C. generator energizes the fields via series resistors which are short circuited by relay contacts when slipping occurs. |
