A.30° B.60° C.120° D.90°
A.較大 B.較小 C.一樣
A.勵(lì)磁電流較小磁路不飽和 B.電樞反應(yīng)去磁作用使磁路不飽和 C.短路時(shí)電機(jī)等效電路參數(shù)為一恒定電阻