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【多选题】
已知一台三相异步电动机的技术数据如下:额定功率4.5KW,额定转速950r/min,f1=50Hz,试求: 1极对数p;2额定转差率SN;3额定转矩TN;A.
解:⑴由已知nN=950r/min与之接近的同步转速n1=1500r/min ∴ P=60f1/n1=60×50/1500=2
B.
解:⑴由已知nN=950r/min与之接近的同步转速n1=1000r/min ∴ P=60f1/n1=60×50/1000=3
C.
⑵ sN=(n1-nN)/n1=(1000-950)/1000=0.05
D.
⑵ sN=(n1-nN)/n1=(1500-950)/1500=0.37
E.
⑶TN=9550PN/nN=9550×4.5×1000/950=45.2×1000N·m
F.
⑶TN=9550PN/nN=9550×4.5/950=45.2N·m
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