Inverter to power EL panel

[Analog_Fan]

https://tinyurl.com/2j49fwep
Out of curiosity, i have drawn something up at the Falstad simulator.
To see if it would make sense to generator a waveform by using a transformer or if you could generate higher voltages from 5V or 12V.
I'm not really a an expert or anything when it comes to transformers.



I have seen some "device" the could generate the 110/120 V AC needed for a EL panel powered by a USB cable (5 Volt) or even powered by a few AAA batteries.

Who has some experience with these Wurth transformers? ... and has some of these laying around and some free time.
: )

I have played with the winding relations in Falstad Simulator, but ....

 

[Analog_Fan]

I have asked the official importer of German BLOCK transformers.

unless you have a big or say huge order and time to wait than they are happy to make you a custom transformer, you only have aces to 9V, 15V, 18V, 24V or standard transformers.

It's for Europeans now a bit harder to importer stuff and you have to pay additional VAT, i have payed up 10€ VAT for something that's worth 10us$ including vat.

it would be cool to be able to make a Teletronix LA‑3A Audio Leveler, using some modern technology, like Wurth transformers.
Mousers sells these.

Wurth transformers
https://www.we-online.com/en/components/products/pbs/power_magnetics/gate_drive_transformers

 

[Bo Deadly]

EL panels are driven with AC. So you don't want the rectifier. And the LA3A uses a line matching transformer to step up the actual signal. A line matching transformer is perfectly fine for this task and can be had from partsexpress for $10 USD. Without digging deeper, those wurth transfomers might not have the inductance for low frequencies. Meaning your leveler might not level low frequencies very well. But I suppose that might be a "feature". Some compressors and limiters that bandpass the sidechain signal are known to work well (e.g. drawmer).

 

[gyraf]

"line distribution transformers" are called 100V-audio in europe e.g.: Produkter - Monacor

 

[Bo Deadly]

"line distribution transformers" are called 100V-audio in europe e.g.: Produkter - Monacor

It's not called that in the US either. I meant to say "line matching transformer" (corrected above). A line distribution transformer is the the big gray barrel at the top of a power pole.

 

[Analog_Fan]

EL panels are driven with AC. So you don't want the rectifier. And the LA3A uses a line matching transformer to step up the actual signal. A line matching transformer is perfectly fine for this task and can be had from partsexpress for $10 USD. Without digging deeper, those wurth transfomers might not have the inductance for low frequencies. Meaning your leveler might not level low frequencies very well. But I suppose that might be a "feature". Some compressors and limiters that bandpass the sidechain signal are known to work well (e.g. drawmer).

Yeah, that's the idea.

to generate AC but stepped up from 12V.
I have asked Wurth once and i got rerouted to the local distributer.
they say it should be possible and pointed to a model.
But that was some time ago and didn't spend more time to research on it.
since you don't wanna buy a load of these transformers and later having them laying around for eternity because you have no use for them.

How ever, i did couple 2 15V German Block transformers back 2 back a couple of months.
Input was +/-220V and output was like +/-214V, the lost was 6volts on the multi meter.
Also it's a pretty big psychical setup and a EL panel requires like 110/120 volt.
It would work for tubes.

I don't have broken SMPS laying around to desolder their transformers.

https://elpanelandtape.co.uk/el-inverters/
https://www.ellumiglow.com/5v-usb-el-inverter
https://www.sparkfun.com/products/retired/10201These work well because they accept anywhere from 2.7-4.2V, so you can use them with batteries quite easily.

Some times ago, i asked a UK based company that makes these things for the schematic, but they never replied.
I think it was this one: EL Panel | EL Wire Craft
https://elwirecraft.co.uk/el-driversinverters-new/
their brand name figures on the "devices".
https://elwirecraft.co.uk/wp-content/uploads/2015/01/6v-el-driver-5m.png
Transformers and Inductors are not my specialty.
But i imagine it can't be that hard.

 

[Brian Roth]

We've discussed this here recently <g>:

https://groupdiy.com/threads/el-pan...riment-for-diy-compressor.80232/#post-1030536
Nothing against Wurth transformers, but the VERY common 70 or 100 Volt line matching transformers seem to me to be the correct choice for an DIY EL compressor design.

Bri

 

[Analog_Fan]

We've discussed this here recently <g>:

https://groupdiy.com/threads/el-pan...riment-for-diy-compressor.80232/#post-1030536
Nothing against Wurth transformers, but the VERY common 70 or 100 Volt line matching transformers seem to me to be the correct choice for an DIY EL compressor design.

Bri

like i said, due to E.U. import tax you could end up paying double vat.
prefer to use standard transformer of 15V and step up.
the Little Wurth transformers are easy to get via Mouser.

the good shop like Don Audio are outside the E.U.



Link to Simulation: https://tinyurl.com/2phgmrcv
at one time i had it over 190 Volt, but lost that setting.
currently: 1 tot 10 ratio.

i added a 100 Ohm resistor to keep the current in check.
but' I'm not sure if the east side setup of the transformer is correct.
Not a specialist on transformer and inductors.
But it needs a load to be able to see something on the scopes.

the input is a 20 V.p.p AC signal.

 

[Analog_Fan]

https://nl.mouser.com/ProductDetail/Wurth-Elektronik/750311959?qs=qSfuJ%2Bfl/d69K1cDmLfyZQ==Datasheet: https://nl.mouser.com/datasheet/2/445/750311959-1723973.pdf

Primary Voltage Rating:	120 VAC
Secondary Voltage Rating:	20 V
Power Rating:	28.6 W
Secondary Current Rating:	1.43 A

Length:	26.04 mm
Width:	26.67 mm
Height:	13.59 mm

20V input, 120V output if connected in reverse.

could this be the one?

 

[Analog_Fan]

I thought of another transformer i used.

1 x 220V, 1 x 9V from Block.
Went to the site of block and selected 2 x 115V, 2 x 9V.
115V is pretty much the magic number to make a EL panel do something.

i made a new schematic for single winded transformer.

simulation: https://tinyurl.com/2fk5pphb

seems you need a opamp than can deliver 25mA.


2 x 115V, 2 x 9V
https://www.block.eu/en_EN/products...d58499f12f88b5de79b5f483302f7161#facettedList
AVB 0,35/2/9
https://www.block.eu/en_EN/productversion/avb-03529/datsheet: https://catalog.block-trafo.de/prodvardatasheet/1703963-2752556_EN

Depth: 22 mm
Height: 15 mm
Width: 22.7 mm

i found another transformer at mouser:

Triad Magnetics F10-250

https://nl.mouser.com/ProductDetail/Triad-Magnetics/F10-250?qs=VZvlzY8g9V%2BsmPhELpwZhg==https://nl.mouser.com/datasheet/2/410/F10_250-780938.pdf

Primary input:	115 VAC
secondary output:	10 V

Depth: 1.38 in
Width: 1.13 in
Height: 1.19 in
€ 8,54

but also no details on the winding or resistance.
I also have no accurate multimeter.

 

[Analog_Fan]

OPA551

Number of channels (#) 1
Total supply voltage (Min) (+5V=5, +/-5V=10) 8
Total supply voltage (Max) (+5V=5, +/-5V=10) 60
Output current (Typ) (mA) 380
Architecture FET

https://www.ti.com/product/OPA551https://www.ti.com/lit/ds/symlink/opa551.pdf
could you use the opamp to drive a transformer?

 

[Analog_Fan]

i got this information from the producer of the transfomer.

Primary winding resistance (1 – 4): 366Ω – 448Ω

Secondary 1 winding resistance (5 – 6): 1.6Ω – 2.4Ω

Secondary 2 winding resistance (7 – 8): 1.8Ω – 3.2Ω



The open circuit inductance of the primary winding is approximately 15H ± 50%. The inductance is based on a drive level of 115V, 60Hz.

that's all i got from them, just now.




Anyone with experience with transformers and LTspice?

need to know the values of R5 & R6.
to prevent excessive current (use) and/or damaging the opamps.
have no accurate multi meter, just a wallmart type.

Have included the LTspice project for ease.

 

[CJ]

Cool deal. I was just thinking about making a stomp box with an EL panel. Although the pigtronix philosophers tone does a pretty good job especially on acoustic guitar.

 

[user 37518]

Anyone with experience with transformers and LTspice?

I can tell you that it's much better than that dreaded Java applet simulator you insist on using. You can simulate leakage and a ton of things, I believe there are some tutorials online. However, it's good to know that you finally decided to learn to use a good sim; that's a big step towards improvement. However, if you really want to go deep into transformer simulation you need an EM simulator, that is, something that actually simulates the EM fields in your transformer. Those simulators are a marvel of modern engineering, but I truly dislike CAD; something mandatory for acurate results.

Regarding your OP: I suggest you use something commercial rather than rolling your own. Power electronic circuits are no joke, specially when you start messing with voltages that are high enough to kill you. What you need is an inverter, or rather a boost converter + inverter. Some solutions out there are specifically tailored towards driving EL panels.

 

[CJ]

I think he is going to use the XFMR backwards so as to drive the panel with audio rather than have the transformer on a power line if I am not sadly mistaken, which is a huge possibility considering my past inhalation habits as related to the sticky icky ,

 

[Analog_Fan]

I think he is going to use the XFMR backwards so as to drive the panel with audio rather than have the transformer on a power line if I am not sadly mistaken, which is a huge possibility considering my past inhalation habits as related to the sticky icky ,

Yeah, backwards, to generate +/-115V from 10V sourced from the op amps.
to light the EL panel, not being obligated to source rare transformers as use in the LA-A3 and so.
to avoid import tax and finance the w*r. over there, i didn't cause that.

the producer of the transformer, the technical deparment told me that's it's possible, although there is a lost due to extra windings.

 

[Analog_Fan]

I can tell you that it's much better than that dreaded Java applet simulator you insist on using. You can simulate leakage and a ton of things, I believe there are some tutorials online. However, it's good to know that you finally decided to learn to use a good sim; that's a big step towards improvement. However, if you really want to go deep into transformer simulation you need an EM simulator, that is, something that actually simulates the EM fields in your transformer. Those simulators are a marvel of modern engineering, but I truly dislike CAD; something mandatory for acurate results.

Regarding your OP: I suggest you use something commercial rather than rolling your own. Power electronic circuits are no joke, specially when you start messing with voltages that are high enough to kill you. What you need is an inverter, or rather a boost converter + inverter. Some solutions out there are specifically tailored towards driving EL panels.

there is nothing wrong with the Falstad simulator, the math is correct, but uses standard models, the guy also makes advanced java applets, also the simulator is partly based on SPICE.
Also professor Aaron Lanterman started using it, after i mentioned.

I'm going to use this transformer, just need to figure out the value of R5, R6.

Secondary 1 winding resistance (5 – 6): 1.6Ω – 2.4Ω

Secondary 2 winding resistance (7 – 8): 1.8Ω – 3.2Ω

3.6 to 6.4 ohm between the outputs of the 2 opamps will probably be very bad.
Should be at least 100 omh, from what i have seen in schematic of using parallel opamp to sum amps.