1. Engineering
  2. Electrical Engineering
  3. 1116 a synchronous motor has a synchronous reactance of 09...

Question: 1116 a synchronous motor has a synchronous reactance of 09...

Question details

11.16 A synchronous motor has a synchronous reactance of 0.9 pu and a tran sient reactance of 0.35 pu. ts stator resistance may be neglected, and it may be considered to be magnetically linear. The motor is initially syın chronized to a balanced supply of 1.0 pu voltage by adjusting its field current to the value that produces an open-circuit voltage of 1.0 pu (a) With the field current left unchanged, load torque is gradually ap- plied. Find the maximum per unit torque that can be applied without losing synchronism (b) Let us assume that the transient time constant is large. Estimate the maximum torque that can be applied suddenly after initial synchro- nization without losing synchronism. It can be assumed that this torque wil be applied for a period that is much less than the transient time constant (c) Suppose the load torque is gradually increased to 1.0 pu and the field current adjusted to give an input power factor of unity. Approxi- mately how much more additional torque can be added suddenly without losing synchronism? (Section 11.3)

Solution by an expert tutor
Blurred Solution
This question has been solved
Subscribe to see this solution