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induction motor never runs at synchronous speed, if it does so there would not be any relative speed between stator flux and rotor and no emf will induce in rotor and we can not apply motor principle as we need current carrying conductor in magnetic field.

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Speed of the stator field of an Induction motor is?

synchronous speed


If a three phase induction motor runs at a speed greater than synchronous speed?

When an induction motor is pushed over synchronous speed it will become a generator and will deliver power back to the utility.


Which motor rotate above synchronous speed?

An induction motor rotating at higher than synchronous speed would be generating power, thus would be a generator. No motor operating as a motor runs above synchronous speed.


Does a induction motor need excitation?

The induction motor is the special kind of motor which runs below and above the synchronous speed. which the synchronous motor runs nearly equal the synchronous speed. The operation of synchronous motor runs with dc field excited hence separate dc field current is given to the field circuit. where as the induction motor the field and main field is drawn from the same supply hence no excitation is required. But due to this separate starting mechanism has to be required in case of the single phase induction motor.


When the induction motor working as induction generator?

An induction motor connected to an existing ac supply normally runs at less than the synchronous speed by an amount described as the 'slip' which is proportional to the torque demanded at the shaft. If the same motor is instead coupled to an engine and driven at a speed higher than the synchronous speed, with negative slip, power then travels back into the ac supply and the motor has become a generator. The amount of power produced depends on the speed. However a normal induction motor will not behave as a stand-alone ac generator. For ac power generation synchronous generators are invariably used because it is necessary to set and maintain the frequency of the supply accurately.

Related Questions

Speed of the stator field of an Induction motor is?

synchronous speed


If a three phase induction motor runs at a speed greater than synchronous speed?

When an induction motor is pushed over synchronous speed it will become a generator and will deliver power back to the utility.


Why is the speed of synchronous motor is more then induction motor?

Synchronous motors run at synchronous speed. An induction motor that has the same number of poles must run at a sub-synchronous speed to create a second magnetic field (a field that is at a different phase angle) to generate torque.


Why doesn't an induction motor run at synchronous speed?

siyudad


Which motor rotate above synchronous speed?

An induction motor rotating at higher than synchronous speed would be generating power, thus would be a generator. No motor operating as a motor runs above synchronous speed.


Difference between induction motor and induction generator?

in case of induction motor the rotor speed is less than synchronous speed giving positive slip but in case of generator the rptor speed is greater than synchronous speed giving negative slip.......


Why single phase induction motor always runs below the synchronous speed?

For exactly the same reason as three-phase motors always run below synchronous speed. If they were to run at synchronous speed then no voltage and, therefore, no rotor current will be induced into the rotor to drive it.


What is a slip in electricity?

it is the difference between the synchronous and asynchronous speed of a induction motor


Does a induction motor need excitation?

The induction motor is the special kind of motor which runs below and above the synchronous speed. which the synchronous motor runs nearly equal the synchronous speed. The operation of synchronous motor runs with dc field excited hence separate dc field current is given to the field circuit. where as the induction motor the field and main field is drawn from the same supply hence no excitation is required. But due to this separate starting mechanism has to be required in case of the single phase induction motor.


What in slip speed control?

slip speed control refers to induction machines s=(synchronous speed-motor speed)/synchronous speed by varying slip the machine can be either be operate in generated mode or motor mode


How do you find the slip in induction motor?

calculate the synchronous speed from the frequency & the no. of magnetic poles in the stator, then measure the actual speed of it with a tachometer, then subtract the actual speed from the synchronous speed.


Explains why a 3-phase induction motor develops no torque when running at synchronous speed?

When rotor speed becomes equal to Synchronous speed in an induction motor, it means that the slip is zero. Which means that there is no cutting of magnetic lines by rotor bars and hence no torque is generated. To generate Torque, rotor speed should always be less than the synchronous speed. That is why, you must have seen in your dailty life that all induction motors are rated below 3000 RPM(sync speed for a 2 pole machine). Sync speed (Ns) = 120f/P