Explanation: Widely used motor/generators such as synchronous and induction machines belong to doubly excited systems, and many other practical applications require multiply excited magnetic systems. 3. In a doubly excited magnetic system with salient pole type stator and rotor, if the rotor is not allowed to move, then the equation for magnetic field stored energy in establishing the currents from zero to is and ir is __________
A. Wfld=1/2 is2Ls+1/2 ir2Lr
B. Wfld=1/2 is2Ls+Mrs is ir
C. Wfld=1/2 is2Ls+1/2 ir2Lr+Mrs is ir
D. Wfld=1/2 ir2Lr+Mrs is ir
Answer:A
Explanation: Widely used motor/generators such as synchronous and induction machines belong to doubly excited systems, and many other practical applications require multiply excited magnetic systems. 3. In a doubly excited magnetic system with salient pole type stator and rotor, if the rotor is not allowed to move, then the equation for magnetic field stored energy in establishing the currents from zero to is and ir is __________
A. Wfld=1/2 is2Ls+1/2 ir2Lr B. Wfld=1/2 is2Ls+Mrs is ir C. Wfld=1/2 is2Ls+1/2 ir2Lr+Mrs is ir D. Wfld=1/2 ir2Lr+Mrs is ir
Explanation: As the rotor is not allowed to move, dWmech=0, thus dWelec=0+dWfld=isdΨs+irdΨr, if in this equation, we introduce the self and mutual inductance terms, (Ψs=Lsis) and integrate the resulting equation from 0 to is, 0 to ir and 0 to iris, the respective terms, finally we get Wfld=1/2 is2Ls+1/2 ir2Lr+Mrs is ir 4.In a doubly excited magnetic system of salient pole stator and rotor, the magnetic torque (Te) depends on