How do the change in supply voltage and frequency affect the performance of three phase induction motor?

If variation in both voltage and frequency occur simultaneously, the effect will be superimposed. Thus, if the voltage is high and the frequency low, the locked-rotor torque will be greatly increased, but the power factor will be decreased and the temperature rise increased with normal load.

How does voltage affect induction motor speed?

With constant supply voltage, lower supply frequency would cause higher V/Hz ratio and higher flux. Higher flux increases the motor torque capability. The speed of the motor is then constant and synchronous (synchronous motors) or close to synchronous (induction motors).

What is the effect of change in supply voltage on starting torque of induction motor?

Effect of Change of Supply Voltage on Starting Torque of 3-Phase Induction Motor. Hence, the starting torque is directly proportional to the square of the supply voltage. Therefore, the starting torque is very sensitive to changes in the value of the supply voltage.

What factors affect induction motor performance?

Motor performance depends on three elements such as voltage across terminals, resistance across terminals, and magnetic force.

How does voltage affect frequency?

As the voltage increases so does the power out of the area and frequency then increases. This oscillation of power, voltage and frequency can last for several seconds. During this time frequency response will start to act to recover the frequency.

What is the effect of change in supply voltage on torque and slip of 3 phase induction motor?

In case of three phase induction motor torque produced is given by T ∝ sV22. If we decrease supply voltage torque will also decrease. But for supplying the same load, the torque must remains the same and it is only possible if we increase the slip and if the slip increase motor will run reduced speed.

Does changing voltage affect frequency?

As the voltage increases so does the power out of the area and frequency then increases. This oscillation of power, voltage and frequency can last for several seconds.

Do voltage and frequency affect the performance of an induction motor?

Effect of Variation of Voltage and Frequency Upon the Performance of Induction Motors (NEMA 14030) “Induction motors are at times operated on circuits ofvoltage or frequency other than those for which the motors are rated. Under such conditions, the performance ofthe motor will vary from the rating.

What happens if you increase the voltage in a DC motor?

Increasing the voltage above the rated voltage increases the speed only slightly and is also much affected by the load. Increasing the voltage by much more than 5\% will cause excessive current and overheat the motor. Increasing voltage increases magnetizing current thus increasing magnetic flux.

How do other performance factors affect the speed of a motor?

Other performance factors generally follow the curve on the graph. Although they are depicted as linear, they rarely are. For instance, as the voltage goes up, the slip decreases, thus increasing the motor’s speed.

How does voltage affect magnetic flux in a motor?

Increasing voltage increases magnetizing current thus increasing magnetic flux. Increasing flux will allow the motor to develop more torque at a given slip or to have less slip at a given load. Less slip means higher operating speed. At or near the rated voltage, the motor reaches a minimum current for a given torque.