F(P,Kx,c,U)=P*Kx/(1.732*U*c)
F(30,0.8,0.8,0.38)

'Ҫϵ() (A)
P=30              'ܹ(KW)
Kx=0.8            'Ҫϵ
U=0.38            'ѹ(KV)
c=0.8             '