SU119922A1 - Braking method of asynchronous motor - Google Patents

Description

In known devices for braking induction motors, the braking mode is carried out in two stages: in the first stage, electric braking is used, and in the second, mechanical, which is carried out until the engine is completely stopped.

The proposed method of braking is more perfect, since it makes it possible to reduce the time and the way of braking while simultaneously unloading the mechanical brake.

For this purpose, current-limiting resistances are introduced into the stator circuit, after which the stator windings are short-circuited, the motor is disconnected from the network, and when it reaches the specified speed, a mechanical brake is applied.

Initially, the motor 1 (see diagram) is electrically operated by short-circuiting its stator windings with a number of contactors 2. For a limited short circuit current, the limiting resistances 3, which are shunted during normal operation by contactors 4, are then disconnected by stator contactors 5, a mechanical brake 6 is applied to the rotor shaft and to the motor to stop completely.

Subject invention

The method of braking an asynchronous motor in two steps - first electrically, and then applying a mechanical brake to a complete stop, characterized in that, in order to reduce the time and way of braking while simultaneously unloading the mechanical brake, current-limiting resistances are inserted into the stator circuit, then the clamps the stator windings are short-circuited, the motor is disconnected from the mains, and when the motor reaches a predetermined speed, the overlays provide a mechanical brake.

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