Yes i know your situation.
All parameters are changing all the time so how do you calculate anything.
Well.......you fix at a particular position, and calculate for that position.
So take it at mains peak. Take the voltage there as a static case.
So do a flyback converter operating at mains VACrms*(sqrt(2))....Double the output power, and vout same as yours.
..you double the pout as at mains peak, a PFCd flyback is transmitting 2*pout(av)
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Hi
Your Flyback design is as attached...this was 10 minutes work.
When you play with the sim you can see whats going on and know how to "mold" the design.
I will send you the LTspice sim of this soon.
LTspice is a free download from linear.com (analog.com)
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As discussed, attached is your 220VAC, 36V, 0.5A Flyback PFC attached..in the free LTspice simulator
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By the way, the sim is openloop......i didint put the feedback in as the sim takes ages with PFC'd feedback becuase pfc feedback loops are so slow.
I am sure you will be able to put in a error amp with a slow feedback compensator if you want to.
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by the way, bpsemi.com chips are in all the led lights sold in uk....but i am pretty sure you cant buy the actual chips in UK, or in Europe or USA(?)
Yes the formulae used are basic. ..
Its mainly V=L.di/dt (Lenzs Law)
And power = 0.5*L.I^2.f (gives power in inductor with current peaking to I amps at freq f)
Also, NP.IP = NS.IS
etc etc