T
treez
Guest
Hello,
Supposing i am doing an LLC resonant converter with an integrated transformer...using AN 4151 by Fairchildsemi i work out that i need a leakage of 200uH and a primary magnetising inductance of 800uH and a turns ratio np/ns of 3:1
The thing is , by calculation i need a secondary which is 89uH to correspond to the 3:1 turnsratio.
But ..problem, not all the primary is coupled with the secondary, so how do i know how many of the primary turns are actually coupled with the secondary.?......it cant be found......so how do i calculate the number of secondary turns needed if Np = 30?
If i measure the primary with secondary open, then i am measuring the combination of leakage and magnetising inductance.....so presumably i have to subtract 200uH from 800uH and then assume that my primary magnetising inductance is really 600uH....is this so?
Supposing i am doing an LLC resonant converter with an integrated transformer...using AN 4151 by Fairchildsemi i work out that i need a leakage of 200uH and a primary magnetising inductance of 800uH and a turns ratio np/ns of 3:1
The thing is , by calculation i need a secondary which is 89uH to correspond to the 3:1 turnsratio.
But ..problem, not all the primary is coupled with the secondary, so how do i know how many of the primary turns are actually coupled with the secondary.?......it cant be found......so how do i calculate the number of secondary turns needed if Np = 30?
If i measure the primary with secondary open, then i am measuring the combination of leakage and magnetising inductance.....so presumably i have to subtract 200uH from 800uH and then assume that my primary magnetising inductance is really 600uH....is this so?