1.最小輸入電壓 Vimin=ViACmin*1.2=210V
2.匝比 n=[Vimin/(Vo+Vf)]*[Dmax/(1-Dmax)] n=[210V/(21V+1V)]*[0.45/(1-0.45)] n=7.8
3.副邊峰值電流^IsB=2*IoB/(1-Dmax)
^IsB=2*2.4A/(1-0.45)
^IoB=8.72A
4. 次級電感 Ls=(Vo+Vf)*(1-Dmax)*[1/(Fs*1000)]/^IsB*1000000
Ls=(21V+1V)*(1-0.45)*[1/(60KHz*1000)]/8.72A*1000000
Ls=23.58Uh
5. 原邊電感 Lp=n*n*Ls Lp=7.8*7.8*23.58uH Lp=1434uH
6. 計算連續(xù)模式時的副邊峰值電流.
^Isp=Io/(1-Dmax)+(^IsB/2)
^Isp=3A/(1-0.45)+(8.72A/2)
^Isp=9.81A
7. 計算連續(xù)模式時的原邊峰值電流.
^Ipp=^Isp/n
^Ipp=9.81A/7.8
^Ipp=1.257A
三.匝數(shù)計算.
1. 原邊匝數(shù) Np=Lp*^Ipp/(^B*Ae) Np=1434uH*1.257A/(0.2*84.8) Np=106.28T
取整 Np=106T
2.副邊匝數(shù) Ns=Np/n
Ns=106T/7.8
Ns=13.58T
取整 Ns=14T
3.反饋匝數(shù) Nv=(Vcc+Vf)/[(Vo+Vf)/Ns]
[復(fù)制鏈接]
2.次級線徑.
元器件計算
