Split Flux Transformer

[seaad]

Today I have conducted some tests with the aim of better accuracy and comparison.

1) I did first a test with the original 5 leg trafo measured with both my Fluke multimeter and with my Oscilloscope. See below.

2) Then a test with a Special 5 leg trafo where the two cross flux legs (U-cores) are fitted between the primarys and the secondary.
This rises the output voltage but lower the OU effect!

3) And at last a test with a normal transformer konfig,.

All tests are at 10 kHz.  And the load resistos are chosen so they reduces the free "swinging" output voltage to about halv  that voltage,  in all tests.

1a)  5-leg               FLUKE      IN:  1,95 V   0,95 mA     74 degrees        OUT:  1,162 V    107,1 %                        10KHz      Load 2469 Ohm
1b)  5-leg               SCOPE     IN:  3,4 V     3,4   mA     74 degrees        OUT:  2,04 V      105,8 %     1,68 mW      10 kHz     Load 2469 Ohm

2)   5-leg  Special   SCOPE     IN:  3,37 V  3,0 mA       70,4 degrees      OUT:  2,72 V      104,75 %    3,56 mW      10 kHz     Load 2080 Ohm

3)   Normal trafo    SCOPE     IN:  3,11 V  10,85 mA    58,25 degrees   OUT:  2,99 V       98,9  %      17,56 mW     10 kHz     Load 509 Ohm

Regards Arne

[lancaIV]

Good  progress, remarkend also the good " normal trafo" efficiency !
Caution and als advice : http://practicalphysics.org/explaining-rms-voltage-and-current.html
One important point : source - primary anf secondary-load " inrush a.voltage b.current" behaviour !?
Sincerely
OCWL

[nul-points]

thanks seaad


i hope to try for a repn. (not sure how close i can get to the core topology), after i finish my current set of datalogging with my WithFeedback circuit


your results looking good - i'm hoping the high efficiency will also apply to pulse operation!


np

[seaad]

Just one clarification to my previous post.

In this case may not the expression "normal transformer" is fair because I used two primary coils here, in parallel.
In the same way they are used in the 5 leg trafo.

Regards Arne

[lancaIV]

A-ha, really important ! Did not known that " normal one" would get such efficient work , even by 10 KHz !Especially by this low voltage step down level !
Material and saturation  ! B/H core specification

Trimming and dimming the charge by capacitive winding, a. primar-y/ ies later b. secondary :
http://translationportal.epo.org/emtp/translate/?ACTION=description-retrieval&COUNTRY=DE&ENGINE=google&FORMAT=docdb&KIND=U1&LOCALE=en_EP&NUMBER=29910512&OPS=ops.epo.org/3.2&SRCLANG=de&TRGLANG=en