問(wèn)答題
【計(jì)算題】
有臺(tái)三相異步電動(dòng)機(jī),其額定轉(zhuǎn)速為1470r/min,電源頻率為50Hz。在(a)起動(dòng)瞬間,(b)轉(zhuǎn)子轉(zhuǎn)速為同步轉(zhuǎn)速的2/3時(shí),(c)轉(zhuǎn)差率為0.02時(shí)三種情況下,試求:
(1)定子旋轉(zhuǎn)磁場(chǎng)對(duì)定子的轉(zhuǎn)速;
(2)定子旋轉(zhuǎn)磁場(chǎng)對(duì)轉(zhuǎn)子的轉(zhuǎn)速;
(3)轉(zhuǎn)子旋轉(zhuǎn)磁場(chǎng)對(duì)轉(zhuǎn)子的轉(zhuǎn)速(提示:
);
(4)轉(zhuǎn)子旋轉(zhuǎn)磁場(chǎng)對(duì)定子的轉(zhuǎn)速;
(5)轉(zhuǎn)子旋轉(zhuǎn)磁場(chǎng)對(duì)定子旋轉(zhuǎn)磁場(chǎng)的轉(zhuǎn)速。