机电传动控制复习题

一般nN=(0.94-0.98)n0 n0=nN/0.96=1000 r/min SN= (n0-nN)/ n0=(1000-960)/1000=0.04 P=60f/ n0=60*50/1000=3 ③ η=PN/P输入 P输入=3/0.83=3.61 5：解： PN=UNINηN

7500W=220V*IN*0.885 IN=38.5A

TN=9.55PN/nN=47.75Nm

6：① n0=UNnN/(UN-INRa)

=220*1500/220-34.4*0.242 = 1559r/min TN=9.55PN/nN =9.55*6500/1500 =41.38Nm

1559

41.38 ② n=U/Keφ-(Ra+Rad)T/KeKtφ2

= U/Keφ-(Ra+Rad)T/9.55Ke2φ2 当3Ω n=854r/min 当5Ω n=311 r/min

③ n= U/Keφ-RaT/9.55Ke2φ2 当UN=0.5UN时 n=732 r/min n0=UNnN/2(UN-INRa) =780 r/min

④ n= U/0.8Keφ-RaT/9.55Ke2φ20.82 当φ=0.8φ时n=1517 r/min

n0=UNnN/0.8Keφ =1964 r/min

n0

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