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 StatesPosts: 961 |
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 chokes be warned i am good parrot but Dumber than a box of rocks |
||||
renewableMark Guru Joined: 09/12/2017 Location: AustraliaPosts: 1678 |
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: AustraliaPosts: 460 |
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: AustraliaPosts: 4406 |
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: AustraliaPosts: 460 |
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 Andrew |
||||
Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
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 StatesPosts: 961 |
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 way be warned i am good parrot but Dumber than a box of rocks |
||||
mackoffgrid Guru Joined: 13/03/2017 Location: AustraliaPosts: 460 |
Nice looking C cores. Is that E core from a microwave oven? |
||||
BenandAmber Guru Joined: 16/02/2019 Location: United StatesPosts: 961 |
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 Transformer be warned i am good parrot but Dumber than a box of rocks |
||||
Print this page |