load torque

When engaged, the load torque on each pawl transfers to the others to keep them engaged.

External load torques, perhaps caused by friction, give rise to a small error in position when the motor is stationary.

The basis of the new method is to monitor the system's ration and, as each step is completed, determine the load torque.

As the load torque increases beyond breakdown torque the motor stalls.

Variable-frequency drives are also categorized by the following load torque and power characteristics:

Another type, for low load torque, has flats ground onto a conventional squirrel-cage rotor to create discrete poles.

A designer may include a safety factor between the rated torque and the estimated full load torque required for the application.

Anticipating load torques produced by voluntary movements.

The time taken for the motor to come to rest depends on the inertia of the rotor-load combination and the load torque including mechanical friction.

(5.14): The maximum operating speed with zero load torque can be found by substituting into Eqn.

Typical pull-out torque and load torque characteristics are shown in Fig. 6.7(a).

However the ministep drive is an open.loop system and, like all such systems, is prone to external disturbance, in this case from load torques.

There is a part of each step during which the motor torque is less than the load torque, so that the system decelerates.

Now consider the effect of applying a load torque equal to the pull-out value, so that the motor has to produce the maximum available torque.

Only four steps are required to decelerate the motor, as the load torque contributes to the decelerating torque.

Motor Full Load Torque is given by:

A robust control design, having the feature of insensitivity to parameter variations and load torque disturbances is highly demanded in many modern variable drive systems.

At a stepping rate f the pull-out torque is denoted by and the load torque by.

The motor must develop enough torque to balance the load torque and the rotor is therefore displaced by a small angle from the expected step position.

A load torque 7L displaces the rotor front the demanded position and introduces a static position error, which may be many ministeps.

The maximum load torque that can be applied to a motor without losing its synchronism is called steady state stability limit of a synchronous motor.

With a load torque of 0-75 Nm the motor must move approximately 8 degrees from the step position, until the torque developed balances the load.

(6.7) and rearranging: So the load torque assists the motor torque in decelerating the system inertia.

The asynchronous traction motor can run on a single RPM determined by the frequency of the feeding current and the loading torque.