Thane Heins Perepiteia Replications

[wattsup]

To cog or not to cog. That is the question. lol

@baroutologos

Don't mind @TH. His style is someimes rough (hey mine can be too) but he is all around OK and trying to help us within his own limitations, as we all.

@all

No one answered my question regarding square versus round coil/magnets but a recent link put up on this thread covered it pretty well. Seems both types have their strong points..

Have not heard from the C-core maker.

I don't think I will be able to spend 8 hours winding a coil so I am looking at any other ready made low cost alternatives.

I have been looking on e-bay for laminated cores and have found a few using the phrase "transformer core".

In the photo below, what if such a transformer was simply (and slowly) cut in half through the laminates right between the coils. It would give two coils with two specs. The primary side has two windings already to go from 110 to 220 vac. The secondary side has more windings but there may be a way of bifilaring the connections.

That link is here.
http://cgi.ebay.com/56W-R-Core-Transformer-110V-200V-for-USB-1798DAC_W0QQitemZ290325387155QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item4398bdd793&_trksid=p3286.c0.m14

Here are a few others on Ebay.
Same as above but higher output.
http://cgi.ebay.com/100W-R-Core-Transformer-115V-230V-Pre-amplifier-DAC_W0QQitemZ250467353863QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item3a51048507&_trksid=p3286.c0.m14

This one looks very interesting.
http://cgi.ebay.com/Push-pull-single-end-Audio-output-transformer-core-kit3_W0QQitemZ260450649994QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item3ca411878a&_trksid=p3286.c0.m14

[minde4000]

All crap and red herrings as usual... our problem is not "cogging torque" this is a term specifically related to continuously cored induction motors where the gap between the laminations causes 'cogging torque'

Use the right term, "core drag" for this prominent problem.

Ron

And this high "core drag" or "core losses" that I am experiencing is because of improper laminate material? (at least in my case?)

Minde

[Nali2001]

You are right R,
I said that cogging is hardly a loss in a system, because it is compared to the real losses like Lenz, Eddy and hysteresis drag. So indeed the placing of the cores in Muller layout will not change the above stated core based losses. I'm well aware of core losses lol.

Steven, this is a great simplification that may have some small merit factor.
But it ignores the main core losses of eddy and hysteresis losses. There is no avoiding these losses by staggering the core magnet ratio.

Each core has an associated loss and these losses are directly additive.
The only core that has no core loss is an air cored coil.

Baroutologos, Minde, and myself have all published our numbers that show core loss is present.

Regards,

Ron

[Nali2001]

See here:
http://www.mkmagnetics.com/dataSheets/pdf/brochure051104.pdf
It states losses and intended max frequency's.
I have ordered custom Finemet Ft3 cores from them and this material is more expensive then you think lol. Square 50 is also a material typically intended for saturatable reactors. It offers very square Bh loops. But it is also very expensive.

I'M NO MAGNETICS DESIGNER BUT I LIKE THIS ONE...

Square 50 - 50% Ni/Fe/ alloy, (grain oriented). It offers the highest squareness ratio (lowest saturated reactance) and very high gain. This material has Bm while cores losses are low enough to consider its use in higher frequency applications than the silicon steels. Applications include bi-stable switching devices, inverter transformers, high performance power magnetic amplifiers, linear current transformers, timing devices, driver transformers, and wherever an extremely square loop material, manufactured to close tolerance, is required.

DON'T LIKE THIS ONE...

Microsil - 3% Si/Fe - Oriented Silicon Iron Alloy. This material is generally used for high power, relatively low frequency applications in high performance power transformers, saturable reactors, inverter transformers, magnetic amplifiers (power), current transformers, output transformers, etc. This is the least expensive of the square loop materials and has high maximum flux. The Squareness ratio is lower than for Square 50. The core losses are higher while gain is significantly lower.

AS I SAID EARLIER CORE CHOICE IS REALLY NOT AN ISSUE RIGHT NOW EXCEPT FOR YOUR HEATING PROBLEM WHICH SUGGESTS YOU NEED A HIGHER FREQUENCY CORE MATERIAL.

IT HAS BEEN ESTABLISHED ALREADY THAT MORE EFFICIENT - HIGHER GRADE CORES INCREASE OVERALL PERFORMANCE.

DO YOU HAVE THE MATERIAL NAME RATHER THAN JUST THE THICKNESS?

T

[Nali2001]

Online shop for all kinds of C cores (also other cores shapes) http://www.alphacoredirect.com/index.html?lmd=39634.474294 Prices are good, also for custom cores. Good quality also.

To cog or not to cog. That is the question. lol

@baroutologos

Don't mind @TH. His style is someimes rough (hey mine can be too) but he is all around OK and trying to help us within his own limitations, as we all.

@all

No one answered my question regarding square versus round coil/magnets but a recent link put up on this thread covered it pretty well. Seems both types have their strong points..

Have not heard from the C-core maker.

I don't think I will be able to spend 8 hours winding a coil so I am looking at any other ready made low cost alternatives.

I have been looking on e-bay for laminated cores and have found a few using the phrase "transformer core".

In the photo below, what if such a transformer was simply (and slowly) cut in half through the laminates right between the coils. It would give two coils with two specs. The primary side has two windings already to go from 110 to 220 vac. The secondary side has more windings but there may be a way of bifilaring the connections.

That link is here.
http://cgi.ebay.com/56W-R-Core-Transformer-110V-200V-for-USB-1798DAC_W0QQitemZ290325387155QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item4398bdd793&_trksid=p3286.c0.m14

Here are a few others on Ebay.
Same as above but higher output.
http://cgi.ebay.com/100W-R-Core-Transformer-115V-230V-Pre-amplifier-DAC_W0QQitemZ250467353863QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item3a51048507&_trksid=p3286.c0.m14

This one looks very interesting.
http://cgi.ebay.com/Push-pull-single-end-Audio-output-transformer-core-kit3_W0QQitemZ260450649994QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item3ca411878a&_trksid=p3286.c0.m14