Induction Motor Voltage And Slip Relation

[kana]

Dear All,

 

Please advice if the induction motor slip will vary if the input voltage to the motor is varied.

 

Let's take a 400V, 50Hz, 15kW motor operating at rated load is supplied by 420V or 380V.

 

At 420V should the slip reduce at rated load in order to deliver the same torque?

 

For 380V should the slip increase at rated load in order to deliver the same torque?

 

I would also appreciate if someone can advice if the torque produced by the motor will match the torque required by the load. That means irrespective of what voltage is applied, the torque produce by the motor will try to match the torque required by the load and will not produce higher or lower torque if the voltage is varied.

 

If 420V is applied to the motor instead of 400V what are the significant losses in the motor? I believe there is a slight increase in stator and core losses.

 

Thanks,

 

Regards,

Kana