| 摘要 |
A method for D.C. braking a three-phase asynchronous machine and a circuit arrangement useful in implementing the method. For braking, the first and third stator windings are separated from their phases and a pulsating direct current is caused to flow from the second phase to the first phase via a closed second switch and a diode. The third winding is short-circuited by a third switch which is connected in a loop with a current transformer; the loop carries a current induced by the turning rotor. A signal from the current transformer flows, via a limit indicator, to a digital logic member (OR). When the motor stops, short-circuit current flow is no longer detected, the second switch is opened and the circuit for producing direct current is automatically disconnected.
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