1.

In a single phase cylindrical rotor synchronous machine, the torque Te tends to ____________ the space angle θr.(a) reduce(b) increase(c) maintain constant(d) all of the mentionedThis question was posed to me at a job interview.This is a very interesting question from Elementary Synchronous Machines in chapter Basic Concepts in Rotating Machines of Electrical Machines

Answer»

The CORRECT answer is (a) reduce

To EXPLAIN: Wfld(is,IR,θr)=1/2 is^2Ls+1/2 ir^2Lr+ isirMmaxcosθr

Torque, Te=∂Wfld(is,ir,θr)/∂θr= -isirMmaxsinθr

Negative sign indicates that the torque Te TENDS to reduce angle θr.



Discussion

No Comment Found

Related InterviewSolutions