Assuming no losses, ,
First is 1.00 TUF, also power factor 1.00
Second would limit to the same (but would take an infinite amount of time to reach it...)
Some examples from PSUDII:
Bridge, Cap input, using starting default values: 76 VA in secondary, 40 watts out, 1.6 watts resistive loss in transformer - TUF about .53
Choke input, defaults: 22.8 VA in, 17.4W out, 0.3W loss in transformer and choke - TUF about .76
I would have used SPICE, but it hasn't been run in a while - updates would take half an hour before I could do anything.
First is 1.00 TUF, also power factor 1.00
Second would limit to the same (but would take an infinite amount of time to reach it...)
Some examples from PSUDII:
Bridge, Cap input, using starting default values: 76 VA in secondary, 40 watts out, 1.6 watts resistive loss in transformer - TUF about .53
Choke input, defaults: 22.8 VA in, 17.4W out, 0.3W loss in transformer and choke - TUF about .76
I would have used SPICE, but it hasn't been run in a while - updates would take half an hour before I could do anything.
First is 1, yes.
But not so sure about the second, i would thinck current would be 1 but voltage dc content only 0.9, so overall should be 0.9.
Third is the most common but also the most tricky one, because the current distortion has to be factured in,
so it should be less than 0.9.
That 0.813 i got from a paper, published by Cern.ch, where the author compared the transformer utilisation factor
of differnt dc supplies for supplying dc power to the magnets they use.
He worked through all the possible options there are, from 1 phase halfwave to 3 phase multipole rectification.
Good examples Tom, both show how the required transformer VA rating is easely underestimated when taking a dc power
multiplication factor of only 1.6 for C input, or 1.11 for L.
But not so sure about the second, i would thinck current would be 1 but voltage dc content only 0.9, so overall should be 0.9.
Third is the most common but also the most tricky one, because the current distortion has to be factured in,
so it should be less than 0.9.
That 0.813 i got from a paper, published by Cern.ch, where the author compared the transformer utilisation factor
of differnt dc supplies for supplying dc power to the magnets they use.
He worked through all the possible options there are, from 1 phase halfwave to 3 phase multipole rectification.
Good examples Tom, both show how the required transformer VA rating is easely underestimated when taking a dc power
multiplication factor of only 1.6 for C input, or 1.11 for L.
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Hi Piotr,
I found your previous thread on EL86 parallel single ended triode design. The THD measurement you showed here is even better than the previous one. Can you share the updated schematic?
Also, do you happen to have the triode strapped EL86 curve or LTspice model? If so, can you post them? If not, what is the bias current and cathode voltage for EL86 in your circuit?
There is some info here: https://www.diyaudio.com/community/threads/vacuum-tube-spice-models.243950/post-4348840