1
\$\begingroup\$

I would like to ask how much is the maximum efficiency of a High-Frequency Transformer (In my application P=10 kW, f=25kHz ), considering the winding resistance, the core losses as well as the magnetizing inductance.

I saw a research about a 1 MW High-Frequency Transformer working at 50 kHz with maximum efficiency 99.6% and I was wondering if this efficiency is realistic.

Based on your experience is it possible to have 99.6% efficiency in my application? If not how much is the maximum efficiency that I can expect?

P.S. I know that there are a lot of factors that affect the performance of the transformer, for example, the material of the core, but at this point, I just need to know theoretically the maximum efficiency that I can succeed.

\$\endgroup\$
  • \$\begingroup\$ yes that is possible but if you dont understand where skin effect , eddy current losses occur with RF transformer and balun design, dielectric and magnetic properties , nonlinear switches , conjugate matching, you have a lot to learn. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jul 8 '17 at 0:27
  • \$\begingroup\$ So, for a 1000kW transformer you saw, what were the technical details of implementation that allow the authors of published research to achieve 99.6%? Then just copy their design, if the details are solid. \$\endgroup\$ – Ale..chenski Jul 8 '17 at 1:07
1
\$\begingroup\$

It is basically an economic question, you can get almost arbitrarily close to 100%, the price just rises exponentially, massive cores at very low flux density, wound with superconducting cables, in liquid helium? Sure you could do it, but it makes no sense.

there is also little point in making the transformer very much better efficiency wise then the rest of the circuit, if you are overall say 95% efficient, so 500W or so of waste heat, but the transformer is 99% efficient (so it contributes 100W of that 500W), then making the transformer 99.9% efficient will leave your total power losses at 410W, getting the drive electronics efficiency up would pay bigger dividends. That last 0.9% has exploded the cost of that transformer, probably by at least 1000%.

\$\endgroup\$
  • \$\begingroup\$ Thank you for your answer. So, based on your experience, for a 10 kW transformer ( that will be used in order to create a Dual Active Bridge DC/DC Converter for an electrical vehicle charger) how much should be the maximum efficiency of the transformer if we take into consideration the cost. \$\endgroup\$ – Yiannis S. Jul 9 '17 at 19:16
  • \$\begingroup\$ You need to do some modelling, there are cost/size/cooling/reliability tradeoffs here, and it very much depends on the detail of exactly where in that configuration space your optimum is. Talk to your magnetics design engineer, also likely magnetics vendors and the electronics/mechanical and thermal people, they will all have an input into this. \$\endgroup\$ – Dan Mills Jul 9 '17 at 20:06

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.