How can I unbalance a synchronous machine?

I need a set of stator currents of synchronous machine in an unbalanced mode. How can I get the unbalanced mode?

Answer 1

[Anuj]

The voltage supply equations can be changed to induce current imbalance. Suppose you are applying 3-phase voltage to the system Like Vs Sin(ωt), Vs Sin(ωt − 2π/3),Vs Sin(ωt + 2π/3), change one phase voltage to (Vs-V0) Sin(ωt) and rest same, then change other/two phase voltages.. This will induce voltage imbalance and that will further induce current imbalance.

[Shivakumar]

My problem is to note down the values of stator currents in balanced and unbalanced condition. Now, to the 400V, 8.1kVA, 1500RPM. I've applied 133.3 three individual 1-phase sources. I dont know why that stator currents dont come in a symmetrical way. Please help me to solve this so that stator currents come in a symmetrical way. And secondly, please explain how to unbalance. I need these solutions urgently. Thanks in advance

[Anuj]

You will have to post your model here so that it can be seen,whats the problem, why is stator current not symmetric. and again, as i said above to unbalance, just change the magnitude of one phase voltage.

[Shivakumar]

I've attached the model here. Please check.

[Anuj]

You should apply 400V in the all 3 voltage source, not 133.3, You will get the symmetric current and to get unbalance, change one source voltage to suppose 380 and then you will see the unbalance in the stator current. I hope, it helps.

[Shivakumar]

I am sorry for giving late reply. But I thank you for solving my problem.

[Anuj]

I am glad that your problem is solved, You can accept the answer so others can be benefited too.

Regards

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/29922-why-your-question-is-not-urgent-or-an-emergency

[Shivakumar]

Anuj.. Can you please tell me why I should use only 400 volts and not 133.3?

[Anuj]

Its a simple convention for a 3-phase supply, when you supply a 3 phase winding, you do apply a peak voltage Vm to each of the three phase, not Vm/3.