How does an increase in load affect a synchronous motor?
In another word, it can be said that even if the rotor is rotating at synchronous speed, the rotor slips back in space because of the increase in the load. In this process, the torque angle δ becomes larger, and, as a result, the induced torque increases.
When the load on a synchronous motor is increased?
There is a limit to the mechanical load that can be applied to asynchronous motor. As the load is increased, the torque angle δ also increases until the condition arises when the rotor is pulled out of synchronism and the motor is stopped.
Which motor is more stable?
2. Salient pole machines are more stable than cylindrical rotor machines. Explanation: Salient pole machines are more stable than cylindrical rotor machines because of the high short circuit ratio and more real power transfer capability.
How to find the effect of field current on a synchronous motor?
To find the effect of field current variation on synchronous motor we study given below figure. First, we suppose that the motor is connected with inductive load (lagging P.F) so if we increase the field current (I F) it effect is drawn in a given figure.
How does load affect the torque of a synchronous motor?
As the load is increased, the torque angle δ also increases until the condition arises when the rotor is pulled out of synchronism and the motor is stopped. Pull-out torque is defined as the maximum value of the torque which a synchronous motor can develop at rated voltage and frequency without losing synchronism.
How does reactive power work in a synchronous motor?
Now it works like such circuitry that has resistance and capacitor and using a negative value of reactive power (-Q), means now motor providing reactive power Q to the connected system. In the given figure, the graphical representation between field current and armature current of a synchronous motor is drawn.
Is the excitation voltage of a synchronous motor constant?
The excitation voltage E f is proportional to ϕω, it depends upon the field current and the speed of the motor. Since the motor is moving at a synchronous speed, and the field current is also constant. Hence, the magnitude of the Voltage |E f| remains constant.