On Fri, 26 Aug 2016 05:28:38 -0400, Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote:>On 25 Aug 2016 03:13:12 -0700, the renowned Winfield Hill ><hill@rowland.harvard.edu> wrote: > >>P E Schoen wrote... >>> >>> A second prototype with heavier wire #28: >>> http://enginuitysystems.com/pix/electronics/SCR_Transformer_2989.jpg >> >> Hey, I like that bobbin, where'd you get it, p/n? > >Would a NiZn-core common-mode choke be usable in that application? > > >--spCM chokes use the same high permeability material as signal tfx. Lossy for power apps. Low curie temp. Available in a host of shapes. Wish low loss matl had some of those shapes..... RL
Simple DC-DC converter, FWB, 12/24/48V to 320 or 640V, 500-1000W+
Started by ●August 25, 2016
Reply by ●August 26, 20162016-08-26
Reply by ●August 29, 20162016-08-29
On Fri, 26 Aug 2016 03:05:13 -0400, "P E Schoen" <paul@pstech-inc.com> wrote:>"Tim Williams" wrote in message news:npoh7u$7i7$1@dont-email.me... > >> I love the background, but it doesn't seem to illuminate the present >> project. How do they relate? > >The topology is the same, with no added inductor. My original prototype >transformers had 25 uH leakage inductance, or about 6% impedance. So that >would provide enough to limit the start-up transients. The layer wound >prototype had 2 uH leakage inductance, so it may be more of a problem. I >might want to add some inductance in series with the primary, as I did for a >subsequent simulation (see reply to legg).I also did not see the relevance. Magnetic characteristics don't scale linearly. Energy storage, intentional or otherwise scales with I^2 and V^2, while power throughput is a direct relationship. Surface area for cooling degrades with part volume. Parasitics compound with layer dimensions and xsectional area. You can get away with murder some times at low power levels, simply because the components are over-rated for the app (smaller parts or heat-conducting structures being impractical/unavailable). RL
