解:SN=(n1—nN)/n1×100%=(3000—2910)/3000×100% =3% IN=PN/η N√3UNcosφ N =5×1000 /0.8×√3 ×380×0.86 =11(A) TN=9550PN/nN=9550×5/2910=16.4 (N·m)Tm=λ tN=2×16.4=32.8 (N·m)