结构推理
有一对称磁路如图所示,尺寸单位为cm,铁心由D21硅钢片制成,若要在两侧铁心柱产生磁通F=504′10-4Wb,试求磁通势。
D21硅钢片(H单位为A/m)磁化数据表
B/T00.010.020.030.040.050.060.070.080.09
0.8340348356364372380389398407416
0.9425435445455465475488500512524
1.0536549562575588602616630645660
1.1675691708726745765786808831855
1.288090693396199010201050109011201160
1.31200125013001350140014501500156016201680
1.41740182018901980206021602260238025002640
【正确答案】对称分支磁路,取一半磁路分段,空气隙l0,铁心段l1
l0=0.1′2=0.2cm
l1=(44-14)′2+(72-14-0.1)′2?176cm
S1=S0=504cm2=504′10-4m2
查D21
H0=0.8′106B0=0.8′106
SHl=H1l1+H0l0=(536′1.758+0.8′106′0.2′10-2)A=2543A
F=NI=Hl=2543A
【答案解析】