Home
JAQForum Ver 24.01
Log In or Join  
Active Topics
Local Time 20:46 27 Nov 2024 Privacy Policy
Jump to

Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.

Forum Index : Electronics : Chokes the effect of uh on idle current

Author Message
BenandAmber
Guru

Joined: 16/02/2019
Location: United States
Posts: 961
Posted: 09:44pm 30 Jun 2019
Copy link to clipboard 
Print this post


I wound this choke 15 turns of 6awg

This gave me around 220 uh

What would be the effect of using a choke with more than the recommended uh

And what have you guys figured out about chokesEdited by BenandAmber 2019-07-02
be warned i am good parrot but Dumber than a box of rocks
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1678
Posted: 10:38pm 30 Jun 2019
Copy link to clipboard 
Print this post

Pretty sure Tony said they can't really ever be too big.

There are a heap of threads on chokes here, use the search function at the top of the page, you often find interesting things you weren't looking for when you do that and learn new things.
Cheers Caveman Mark
Off grid eastern Melb
 
mackoffgrid

Guru

Joined: 13/03/2017
Location: Australia
Posts: 460
Posted: 10:39pm 30 Jun 2019
Copy link to clipboard 
Print this post

Ben,

Look at Marks results where he has a ferrite choke and a steel choke, one on each leg. I'm not a Ozinverter builder but I would say this choke will saturate as it appears not to have an air gap.

My Take on it.

The thing is with a PWM inverter you want to filter out the 20kHz pulse before it hits the transformer otherwise you will get undesirable losses in the transformer core.

The high inductance is great for the no-low load situation. As the current increases you will want this inductor to saturate otherwise it may well be too much inductance.

A second steel inductor at a lower inductance, with a decent air gap so it won't saturate, will be desirable.

Tony introduced me to the Swinging Choke 26Volt warpverter - swinging choke which I think has lots of potential.


Cheers
Andrew
 
Warpspeed
Guru

Joined: 09/08/2007
Location: Australia
Posts: 4406
Posted: 12:06am 01 Jul 2019
Copy link to clipboard 
Print this post

I searched the whole internet for something on swinging chokes.

Plenty of people trying to sell them, but absolutely zero on how to make one.

Back in ancient times, before switching power supplies or efficient voltage regulators, swinging chokes were a fairly common thing.

If you google "swinging choke" you will come up with all kinds of fun that married couples play with other married couples, and some rather brutal stuff on self defense. But bugger all on magnetics design.

A sign of the times.......
Cheers,  Tony.
 
mackoffgrid

Guru

Joined: 13/03/2017
Location: Australia
Posts: 460
Posted: 12:27am 01 Jul 2019
Copy link to clipboard 
Print this post

kinky chokes

Tony, another example of older ideas being lost.

I had never heard of swinging chokes before you told me about them. I did do a google search on them I and also found bugger all on their construction etc but saw that they were used in high voltage power supplies for valve amplifiers and such.

I'm quite interested in them. To profile the inductance of the choke seems very useful.


Ben, I hope you read through this recycling AeroSharp Chokes, you will likely find it interesting.

Cheers
AndrewEdited by mackoffgrid 2019-07-02
 
Warpspeed
Guru

Joined: 09/08/2007
Location: Australia
Posts: 4406
Posted: 03:01am 01 Jul 2019
Copy link to clipboard 
Print this post

You can also do it with some of the poorer grades of powdered iron that have a very soft saturation characteristic, but the inductance swing will not be that large.

With a steel core, and a wedge shaped air gap 10:1 inductance change is quite practical.

Only real way to play around with this is with a dynamic inductor tester.

Yes you are quite right, back in the valve era, the problem then was that the unloaded power supply voltages could climb to inconvenient levels, and a bleeder resistor was often required to provide some minimum load current to hold the voltage down.

If you had a swinging choke, far less bleeder power was required to be thrown away.

But I am astonished that all this old engineering has completely vanished from the public domain. All the old time transformer designers still know all about it, because you can still order new swinging chokes, or get one designed and manufactured.


Cheers,  Tony.
 
BenandAmber
Guru

Joined: 16/02/2019
Location: United States
Posts: 961
Posted: 03:32am 01 Jul 2019
Copy link to clipboard 
Print this post











That green one there is out of a 2018 Power Jack

I I guess I'm going to try winding them both of these

Now that I have extra wire might as well have a few extra chokes

I am truly scared to death to run the one

I'm using everyday without a ferrite choke

But I will soon have one for experimenting
with

I was thinking of using two like Mark does

My big inverter has a little over 40 watt idle current

If I remember correctly my little one is 29

That was some good reading Mack off Grid

Warp speed is awesome thanks to you two renewable Mark but this one's awful big



I still like to have all of your guys's opinions too though

So what do you guys think of these two besides them being very very dirty they will clean up nicely

That swinging choke is pretty awesome by the wayEdited by BenandAmber 2019-07-02
be warned i am good parrot but Dumber than a box of rocks
 
mackoffgrid

Guru

Joined: 13/03/2017
Location: Australia
Posts: 460
Posted: 09:26pm 01 Jul 2019
Copy link to clipboard 
Print this post

Nice looking C cores. Is that E core from a microwave oven?

 
BenandAmber
Guru

Joined: 16/02/2019
Location: United States
Posts: 961
Posted: 02:30am 02 Jul 2019
Copy link to clipboard 
Print this post

It's the choke out of a Hobart welder

it don't have any welds on the E I pieces

It's about two and a half times bigger than the microwave Transformer

And it's easy to take apart

So you don't think the C cores will be too big

They are all very dirty but all of them will clean up and look almost like new

I was thinking that might be out of a century welding machine

If so I have the Hobart one out there




1200 Watt microwave oven Transformer and Hobart choke TransformerEdited by BenandAmber 2019-07-03
be warned i am good parrot but Dumber than a box of rocks
 
Print this page


To reply to this topic, you need to log in.

© JAQ Software 2024