New fresh meat's toys and questions
Tonic, Sat Feb 17 2007, 12:15AMGoddamn, I finally got forum account. A few months ago I tried to get it and sent a few mails, but without responses. Today I've noticed registration is enabled, so, not to loose ocassion, I registered at last.
First, hello to you all. My name is Michal (in english Michael, spanish Miguel
), I'm 19 years old passional guy. I've been playing with variables things, but rather two of them are noteworthy - pumping last droplets from PC perfomance via overclocking, voltage modifications and etc., however it's rather a history. Three years ago I had been sucked in refrigeration, espacieally in low temperature, that's what I was doing for two years. But, becasue of costs I could barely finish projects, so.. I've lured into internet and found accidently a polish forum, where HV things were described. It caught my attention and was looking interesting, so.. a HV passion has begun. I will tell in a shortcuit what I've done (chronologicaly).The first working TV transformer driver was based on one transistor, 2N3055. I had a lot problems at begin, since I didn't even know how transistors work, but at last I've managed it to work. The spark was thiny and only 1cm, but this time I was really happy, it looked so amazingly for me. There are samples of this spark :
In meantime, I got a better power supply made by 100W transformer, rectify bridge and a few capacitors. The results were more impressive, but, of course, not enough for my increasing hungry of sparks! :P
The next step was about bulbs. With 2N3055 driver and one electrode connected to bulb's screw and bottom, the sparks were hardly visible. So, I plugged second electrode to wire, which was bended on buld. Sparks became looking more neat. There are pics :
Later, I bought a TV cascade which multipled voltage a lot and I started to feel fear. Instead of 1cm spark, I've achieved 8cm length one.
On right side, a TV cascade is shown
Unfortunately, I don't have a picture of 8cm spark, but it doesn't look a lot different from 1cm one.
Then, I plugged a bulb and that was the my best success, since it does look really marvelous for me :
Before :
After :
The next step was ZVS driver. A lot of time passed before I got this driver to work. There's photo of elements :
First revision of ZVS, which didn't work :
Testing :
The problem was caused by unproper connecting fast diodes's outputs. At this time I didn't know if it does make difference, so I've decided to make a first home made PCB and do it a bit more professional :
The entire setup :
It finally worked. A nice, fire-like, fatty and white spark that can be stretched a lot.
Picture of spark :
From this time I started to weak driver. I've made another PCB :
Next, I put two primary windings on one ferrite core and connected them in series. That theoretically doubled output voltage, in practice it made spark a bit thinner but a lot longer. There are last pics of spark that I have on disk :
This revision gave a spar that could be stretched to about 7cm. After last tweaking, I was able to get 10cm ;) But there I have a question, from what a output voltage/current ratio depends? Is there a way to set ZVS in way that it would produce more voltage and less current?
Now, I'm trying to learn about halfbridge and fullbridges, since I didn't find another simple driver more powerful than ZVS. From what I know, a half bridge with two transistors steered by a chip (example, IR2153) that makes switching transistors gates in first-second-first-second etc. way, sounds a good candidate for me, especially when I have some of parts. But I can't find basic informations, how a halfbridge works, what's are the most important elements, etc. Would anyone give any interesting links about it?
Re: New fresh meat's toys and questions
Coronafix, Sat Feb 17 2007, 09:42AM
Bloody nice photos of the bolt and arc!
Very inspiring.
Coronafix, Sat Feb 17 2007, 09:42AM
Bloody nice photos of the bolt and arc!
Very inspiring.
Re: New fresh meat's toys and questions
uzzors2k, Sat Feb 17 2007, 10:44AM
Welcome to 4HV, sorry to hear you couldn't register sooner. You've sure been busy, and taken some great pictures too, its good to see another new member here.
For the ZVS driver you can change the frequency and voltage by playing with different capacitor and inductor values. (Are you using the mazzilli driver?) I haven't used my ZVS driver for over a year so I can't offer any more advice. Other members here have tweaked the mazzilli driver pretty far though.
About half-bridges and such, check out our HvWiki,
and NEETS There should be some stuff on half-bridges there. Basically a half bridge switches the current in two directions, making a true AC signal. It works by using a capacitor divider to make an artificial ground, which the switches dump power into. The switches are never on at the same time.
uzzors2k, Sat Feb 17 2007, 10:44AM
Welcome to 4HV, sorry to hear you couldn't register sooner. You've sure been busy, and taken some great pictures too, its good to see another new member here.
For the ZVS driver you can change the frequency and voltage by playing with different capacitor and inductor values. (Are you using the mazzilli driver?) I haven't used my ZVS driver for over a year so I can't offer any more advice. Other members here have tweaked the mazzilli driver pretty far though.
About half-bridges and such, check out our HvWiki,
and NEETS There should be some stuff on half-bridges there. Basically a half bridge switches the current in two directions, making a true AC signal. It works by using a capacitor divider to make an artificial ground, which the switches dump power into. The switches are never on at the same time.Re: New fresh meat's toys and questions
Tonic, Sat Feb 17 2007, 07:57PM
And thanks to two transistors, a primary winding's current flows in opposite ways xx-xxx kHz times in second? The larger frequency is, a higher voltage output is (if I remember correctly first Faraday's law and according to this, higher frequency creates more magnetic field's stream changes, which cause higher inducted voltage in secondary winding)?
Yes, this is Mazilli's driver. The another trick I should play with is decreasing primary turns in order to obtain higher secondary/primary ratio (how it is called in english?) and output voltage. But it would also decrease primary's resistance and MOSFETs would get hotter.
Hm, I've reminded my actual problem with primary windings. Before anything the whole setup was working greatly - nothing was heating, MOSFETs were barely warm (those are IRFP250), inductor was moderately heated. But after playing with parts, it changed - primary winding started to act as indution heating, heating ferrite core to very high temperature that my finger can't stand. And I've broken in that way two parts of ferrite core, which were surprisingly fragile at high temperature. Despite this heating problem, I can have flame spark, as before. I have no idea what I've done with it. Winding seems to be made correctly, I don't see short-circuits, nothing looking suspicious. I thought it might be caused by wire - it's ~0.5-07mm and at full load driver pumps from PSU somethign around 10-11A. Maybe this wire is too thin? Has anyone a table, where different thicnkess of wire and their max working current are shown?
Tonic, Sat Feb 17 2007, 07:57PM
wrote ...
About half-bridges and such, check out our HvWiki, and NEETS There should be some stuff on half-bridges there. Basically a half bridge switches the current in two directions, making a true AC signal. It works by using a capacitor divider to make an artificial ground, which the switches dump power into. The switches are never on at the same time.
About half-bridges and such, check out our HvWiki,
and NEETS There should be some stuff on half-bridges there. Basically a half bridge switches the current in two directions, making a true AC signal. It works by using a capacitor divider to make an artificial ground, which the switches dump power into. The switches are never on at the same time.And thanks to two transistors, a primary winding's current flows in opposite ways xx-xxx kHz times in second? The larger frequency is, a higher voltage output is (if I remember correctly first Faraday's law and according to this, higher frequency creates more magnetic field's stream changes, which cause higher inducted voltage in secondary winding)?
wrote ...
For the ZVS driver you can change the frequency and voltage by playing with different capacitor and inductor values. (Are you using the mazzilli driver?) I haven't used my ZVS driver for over a year so I can't offer any more advice. Other members here have tweaked the mazzilli driver pretty far though.
For the ZVS driver you can change the frequency and voltage by playing with different capacitor and inductor values. (Are you using the mazzilli driver?) I haven't used my ZVS driver for over a year so I can't offer any more advice. Other members here have tweaked the mazzilli driver pretty far though.
Yes, this is Mazilli's driver. The another trick I should play with is decreasing primary turns in order to obtain higher secondary/primary ratio (how it is called in english?) and output voltage. But it would also decrease primary's resistance and MOSFETs would get hotter.
Hm, I've reminded my actual problem with primary windings. Before anything the whole setup was working greatly - nothing was heating, MOSFETs were barely warm (those are IRFP250), inductor was moderately heated. But after playing with parts, it changed - primary winding started to act as indution heating, heating ferrite core to very high temperature that my finger can't stand. And I've broken in that way two parts of ferrite core, which were surprisingly fragile at high temperature. Despite this heating problem, I can have flame spark, as before. I have no idea what I've done with it. Winding seems to be made correctly, I don't see short-circuits, nothing looking suspicious. I thought it might be caused by wire - it's ~0.5-07mm and at full load driver pumps from PSU somethign around 10-11A. Maybe this wire is too thin? Has anyone a table, where different thicnkess of wire and their max working current are shown?
Re: New fresh meat's toys and questions
uzzors2k, Sat Feb 17 2007, 09:26PM
Jepp.
Here is a table with everything you need to know about wire. Lots of people have had their primaries almost melt with the mazzilli driver, but as said I've never run it over 12 volts, so I've never had such a problem. However one of the other members can help you with the mazzilli driver, I don't even know how it works.
uzzors2k, Sat Feb 17 2007, 09:26PM
Tonic wrote ...
And thanks to two transistors, a primary winding's current flows in opposite ways xx-xxx kHz times in second? The larger frequency is, a higher voltage output is (if I remember correctly first Faraday's law and according to this, higher frequency creates more magnetic field's stream changes, which cause higher inducted voltage in secondary winding)?
And thanks to two transistors, a primary winding's current flows in opposite ways xx-xxx kHz times in second? The larger frequency is, a higher voltage output is (if I remember correctly first Faraday's law and according to this, higher frequency creates more magnetic field's stream changes, which cause higher inducted voltage in secondary winding)?
Jepp.
Here is a table with everything you need to know about wire.
Lots of people have had their primaries almost melt with the mazzilli driver, but as said I've never run it over 12 volts, so I've never had such a problem. However one of the other members can help you with the mazzilli driver, I don't even know how it works. Re: New fresh meat's toys and questions
..., Sun Feb 18 2007, 01:08AM
that table is useless for anything that runs at >100hz, as then you have to deal with the skin effect. I was using a 10awg stranded primary on my driver running at 750w of power, and it lasted about 2 minutes before it started to smoke.
..., Sun Feb 18 2007, 01:08AM
that table is useless for anything that runs at >100hz, as then you have to deal with the skin effect. I was using a 10awg stranded primary on my driver running at 750w of power, and it lasted about 2 minutes before it started to smoke.
Re: New fresh meat's toys and questions
Marko, Sun Feb 18 2007, 12:27PM
Hi Michal
You can strand a bunch of enamelled wires for your primary coil if skin effect really troubles you.
Anyway, at over 100kHz, you should be able to push over a kilowatt of power through an average flyback core, enough to destroy most TV flybacks. Core loss also increases heavily with increase of frequency.
To increase output power it's usually enough just to reduce number of primary turns.
Just increasing the frequency will actually lower your output power unless you simultaneously decrease number of your primary turns.
It's actually best for the core if you run it close to saturation at lowest frequency possible.
Marko, Sun Feb 18 2007, 12:27PM
Hi Michal
You can strand a bunch of enamelled wires for your primary coil if skin effect really troubles you.
Anyway, at over 100kHz, you should be able to push over a kilowatt of power through an average flyback core, enough to destroy most TV flybacks. Core loss also increases heavily with increase of frequency.
To increase output power it's usually enough just to reduce number of primary turns.
Just increasing the frequency will actually lower your output power unless you simultaneously decrease number of your primary turns.
It's actually best for the core if you run it close to saturation at lowest frequency possible.
Re: New fresh meat's toys and questions
Tonic, Wed Feb 21 2007, 12:23AM
Well, I digged a bit there and found a few interesting ideas that I want to try ;) These are : capacitors on driver's input, larger radiators, places on PCB for few resonating capacitor (MMC array, in that way I can play with frequency and worry less about heating), second primary coil, as Andrineri done or suggested, separate gate supply etc. In that way that would be a configurable driver, for example, I would replace MOSFETs to IGBTs and try to plug ZVS into main ;)
So, is it a skin effect that causes heating? And why strand instead of fatter wire?
Mechanical vibrations?
Whoa, please, don't make my eyes wanting to jump out Saturation.. that's the term I must learn.
Tonic, Wed Feb 21 2007, 12:23AM
Well, I digged a bit there and found a few interesting ideas that I want to try ;) These are : capacitors on driver's input, larger radiators, places on PCB for few resonating capacitor (MMC array, in that way I can play with frequency and worry less about heating), second primary coil, as Andrineri done or suggested, separate gate supply etc. In that way that would be a configurable driver, for example, I would replace MOSFETs to IGBTs and try to plug ZVS into main ;)
wrote ...
You can strand a bunch of enamelled wires for your primary coil if skin effect really troubles you.
You can strand a bunch of enamelled wires for your primary coil if skin effect really troubles you.
So, is it a skin effect that causes heating? And why strand instead of fatter wire?
wrote ...
Anyway, at over 100kHz, you should be able to push over a kilowatt of power through an average flyback core, enough to destroy most TV flybacks. Core loss also increases heavily with increase of frequency.
Anyway, at over 100kHz, you should be able to push over a kilowatt of power through an average flyback core, enough to destroy most TV flybacks. Core loss also increases heavily with increase of frequency.
Mechanical vibrations?
wrote ...
It's actually best for the core if you run it close to saturation at lowest frequency possible.
It's actually best for the core if you run it close to saturation at lowest frequency possible.
Whoa, please, don't make my eyes wanting to jump out
Saturation.. that's the term I must learn.Re: New fresh meat's toys and questions
Colin 99, Wed Feb 21 2007, 05:35AM
Tonic,
Another suggetion that I was given to increase output was to replace the 12 Volt zeners with 15 or 18 volt ones. I'm using 15 volt zeners now. Also a 0.68uF cap across the center tap of your flyback and ground. Some members dissagree with this one though it does increase output. I'm using 3 SLA batteries for 36 volt operation and it just sizzles. Next I'll have to try lowering the primary turns to 4 and 4 and try the second primary too.
Best of luck,
shaun
Colin 99, Wed Feb 21 2007, 05:35AM
Tonic,
Another suggetion that I was given to increase output was to replace the 12 Volt zeners with 15 or 18 volt ones. I'm using 15 volt zeners now. Also a 0.68uF cap across the center tap of your flyback and ground. Some members dissagree with this one though it does increase output. I'm using 3 SLA batteries for 36 volt operation and it just sizzles. Next I'll have to try lowering the primary turns to 4 and 4 and try the second primary too.
Best of luck,
shaun
Re: New fresh meat's toys and questions
Tonic, Wed Feb 21 2007, 07:41PM
Sounds that you tried a few Zeners diodes, if yes, did you notice any differents?
One capacitor's leg to center tap and second leg to ground? I've never heard of it. But thanks, it wouldn't be a problem to check, if there's a difference.
Although, I have problem with getting higher input voltages than 24V. I'm using 100W transformer 230V->24V AC, after adding rectify bridge and capacitors, it gives something around 35V without load. By the way, why more? I thought if AC and DC give the same power, DC has lower voltage.. Vmax/sqrt(2) minus the voltage drop that occurs in rectify bridge. I must try to get power supply that will give more voltage, since I do actually prefer to see longer and purplish arcs. Flame arcs bored me ;P I thought about voltage doubler or tripler, but I saw a few types of them and I don't know what diodes and capacitors parameters are workable - on www pages I've found only theory, no practical advices that would suit my taste. I want to get higher voltage in simple and cheap way. If anyone can help with it, I would really appreciate it. Since IRFP250s can work at 200V, a 50 DCV would be a great option, knowing that there might be voltage spikes four time higher that input voltage (4x50V=200V and it doesn't get over max IRFP250 operating voltage).
You too ;)
Tonic, Wed Feb 21 2007, 07:41PM
wrote ...
Another suggetion that I was given to increase output was to replace the 12 Volt zeners with 15 or 18 volt ones.
I'm using 15 volt zeners now.
Another suggetion that I was given to increase output was to replace the 12 Volt zeners with 15 or 18 volt ones.
I'm using 15 volt zeners now.
Sounds that you tried a few Zeners diodes, if yes, did you notice any differents?
wrote ...
Also a 0.68uF cap across the center tap of your flyback and ground. Some members dissagree with this one though it does increase output. I'm using 3 SLA batteries for 36 volt operation and it just sizzles. Next I'll have to try lowering the primary turns to 4 and 4 and try the second primary too.
Also a 0.68uF cap across the center tap of your flyback and ground. Some members dissagree with this one though it does increase output. I'm using 3 SLA batteries for 36 volt operation and it just sizzles. Next I'll have to try lowering the primary turns to 4 and 4 and try the second primary too.
One capacitor's leg to center tap and second leg to ground? I've never heard of it. But thanks, it wouldn't be a problem to check, if there's a difference.
Although, I have problem with getting higher input voltages than 24V. I'm using 100W transformer 230V->24V AC, after adding rectify bridge and capacitors, it gives something around 35V without load. By the way, why more? I thought if AC and DC give the same power, DC has lower voltage.. Vmax/sqrt(2) minus the voltage drop that occurs in rectify bridge. I must try to get power supply that will give more voltage, since I do actually prefer to see longer and purplish arcs. Flame arcs bored me ;P I thought about voltage doubler or tripler, but I saw a few types of them and I don't know what diodes and capacitors parameters are workable - on www pages I've found only theory, no practical advices that would suit my taste. I want to get higher voltage in simple and cheap way. If anyone can help with it, I would really appreciate it. Since IRFP250s can work at 200V, a 50 DCV would be a great option, knowing that there might be voltage spikes four time higher that input voltage (4x50V=200V and it doesn't get over max IRFP250 operating voltage).
wrote ...
Best of luck,
Best of luck,
You too ;)
Re: New fresh meat's toys and questions
Colin 99, Thu Feb 22 2007, 12:39AM
Tonic,
When I increased the zeners to 15 volts, it made a difference. I haven't tried anything higher. Obviously it's limited by the max voltage allowable on the gates.
A 100 watt transformer is definatly not big enough! I'm drawing 13 amps maximum at maximum arc length with 36 volts input. That's alot of power
I'm using 36 volts for more power and because my flyback seems to take it, although I had to jumper some of the secondary pins (It had two secondaries) to prevent flash over.
With the high output current that the ZVS mazzilli circuit produces, You'll only get hot orange firery arcs, not blue/purple.
I'm using high voltage high, current IGBTs now and they get really hot (on heatsinks) within 1/2 minute of running a jaccobs ladder.
I hope this helps.
Shaun
Colin 99, Thu Feb 22 2007, 12:39AM
Tonic,
When I increased the zeners to 15 volts, it made a difference. I haven't tried anything higher. Obviously it's limited by the max voltage allowable on the gates.
A 100 watt transformer is definatly not big enough! I'm drawing 13 amps maximum at maximum arc length with 36 volts input. That's alot of power
I'm using 36 volts for more power and because my flyback seems to take it, although I had to jumper some of the secondary pins (It had two secondaries) to prevent flash over. With the high output current that the ZVS mazzilli circuit produces, You'll only get hot orange firery arcs, not blue/purple.
I'm using high voltage high, current IGBTs now and they get really hot (on heatsinks) within 1/2 minute of running a jaccobs ladder.
I hope this helps.
Shaun
Re: New fresh meat's toys and questions
Tonic, Thu Feb 22 2007, 08:27AM
[quote]
When I increased the zeners to 15 volts, it made a difference.
[/quote]
Difference in what? Arc's length, thickness?
Well, that's not that. At max load ZVS driver draws 28V/11A. That's far more than 100W. 100W doesn't mean the transformer's output won't overlimit this power, it just won't stand for long time. When I play with ZVS and switch off, transformer is usually moderately warm and is alive
Yeah, that's why I want to tune it in order to get lower output current and higher outpu voltage.
My guess.. bigger heating is caused by bigger resistance?
Tonic, Thu Feb 22 2007, 08:27AM
[quote]
When I increased the zeners to 15 volts, it made a difference.
[/quote]
Difference in what? Arc's length, thickness?
wrote ...
A 100 watt transformer is definatly not big enough! I'm drawing 13 amps maximum at maximum arc length with 36 volts input. That's alot of power I'm using 36 volts for more power and because my flyback seems to take it, although I had to jumper some of the secondary pins (It had two secondaries) to prevent flash over.
A 100 watt transformer is definatly not big enough! I'm drawing 13 amps maximum at maximum arc length with 36 volts input. That's alot of power
I'm using 36 volts for more power and because my flyback seems to take it, although I had to jumper some of the secondary pins (It had two secondaries) to prevent flash over. Well, that's not that. At max load ZVS driver draws 28V/11A. That's far more than 100W. 100W doesn't mean the transformer's output won't overlimit this power, it just won't stand for long time. When I play with ZVS and switch off, transformer is usually moderately warm and is alive
wrote ...
With the high output current that the ZVS mazzilli circuit produces, You'll only get hot orange firery arcs, not blue/purple.
With the high output current that the ZVS mazzilli circuit produces, You'll only get hot orange firery arcs, not blue/purple.
Yeah, that's why I want to tune it in order to get lower output current and higher outpu voltage.
wrote ...
I'm using high voltage high, current IGBTs now and they get really hot (on heatsinks) within 1/2 minute of running a jaccobs ladder.
I'm using high voltage high, current IGBTs now and they get really hot (on heatsinks) within 1/2 minute of running a jaccobs ladder.
My guess.. bigger heating is caused by bigger resistance?
Re: New fresh meat's toys and questions
Colin 99, Sat Feb 24 2007, 04:07PM
Increase in both thickness and length
I remember that I had a hard time measuring current. I ended up using a current shunt and a DVM some distance away from the circuit before the emf from the ZVS circuit would stop interfering with the DVM. I tried current clamps too.... no good. You might not be measuring the actual current and I can't see how a 100 watt transformer could but out that much power.
Use more batteries or a big transformer.
Try more capacitance on your resonant cap. Its easy and makes a big improvement in arc length.
Shaun
Colin 99, Sat Feb 24 2007, 04:07PM
Difference in what? Arc's length, thickness?
Increase in both thickness and length
Well, that's not that. At max load ZVS driver draws 28V/11A. That's far more than 100W. 100W doesn't mean the transformer's output won't overlimit this power, it just won't stand for long time. When I play with ZVS and switch off, transformer is usually moderately warm and is alive
I remember that I had a hard time measuring current. I ended up using a current shunt and a DVM some distance away from the circuit before the emf from the ZVS circuit would stop interfering with the DVM. I tried current clamps too.... no good. You might not be measuring the actual current and I can't see how a 100 watt transformer could but out that much power.
Use more batteries or a big transformer.
Try more capacitance on your resonant cap. Its easy and makes a big improvement in arc length.
Shaun
Re: New fresh meat's toys and questions
Dr. Dark Current, Sat Feb 24 2007, 06:39PM
do you use a limiting resistor on the output of the cascade? I tried a cascade with a limiting resistor, but it "sprays" heavily and lots of corona, and this decreases output. I'm afraid to run it without the limiting resistor, because I think it can be damaged from current surges.
Dr. Dark Current, Sat Feb 24 2007, 06:39PM
Tonic wrote ...
Later, I bought a TV cascade which multipled voltage a lot and I started to feel fear. Instead of 1cm spark, I've achieved 8cm length one.
hi TonicLater, I bought a TV cascade which multipled voltage a lot and I started to feel fear. Instead of 1cm spark, I've achieved 8cm length one.
do you use a limiting resistor on the output of the cascade? I tried a cascade with a limiting resistor, but it "sprays" heavily and lots of corona, and this decreases output. I'm afraid to run it without the limiting resistor, because I think it can be damaged from current surges.
Re: New fresh meat's toys and questions
Ambar, Sun Feb 25 2007, 03:18AM
I am mounting the ZVS to driver and I am with some you doubt on the functioning of it. For example, which is the maximum frequency that reaches. How many Watts is necessary so that of a hot arc?
Ambar, Sun Feb 25 2007, 03:18AM
I am mounting the ZVS to driver and I am with some you doubt on the functioning of it. For example, which is the maximum frequency that reaches. How many Watts is necessary so that of a hot arc?
Re: New fresh meat's toys and questions
Tonic, Mon Feb 26 2007, 08:59PM
[quote]
I remember that I had a hard time measuring current. I ended up using a current shunt and a DVM some distance away from the circuit before the emf from the ZVS circuit would stop interfering with the DVM. I tried current clamps too.... no good. You might not be measuring the actual current and I can't see how a 100 watt transformer could but out that much power.
Use more batteries or a big transformer.
[/quote]
Hm.. EMF could interfered multimeter measuring, since it was near flyback.
Is it really impossible to get that much power? I don't have any batteries laying around. Probably the best option will be searching a cheap, used transformer from internet auction, I'll look around.
I've added something aroung 2.5uF and gained 3.5uF in total, but it didn't make different, or different was too small to notice. Or something is limiting.
By the way, I've changed primary wire to fatter one, ~1.5mm, but a heating problem still occurs. Do you have any idea how to solve it?
Are you saying about this type of cascade?
From
If yes, then no, I didn't use limiting resistor. I hadn't any reasons for this. You didn't want to damage cascade because of overcurrent? And you did use resitor on output, not input? Well, I don't get it ;)
It reminds how I plugged an cascade to flyback drivered by ZVS. Yeah, a bit stupid idea.. but, before cascade died by large current, it did shot a incredible, marvelous spark long at least 15cm and it was orange colour and quite fat. It really frightened me! What a pity I don't have pic of it ;( But I have an idea to connect TV cascades in parallel. Would it work?
If you are asking about frequencies at which ZVS driver works, I don't know, I'd rather shot that's something between 30-50 kHz.
To have that hot arc, it depends. Just make ZVS driver properly and get a power supply unit that can give at least 10A. Current is a main factory which decides how fat arc will be.
BTW, I'm re-asking - can anyone help with doubler? I have a 100W transformer with 1x24V AC output and I want to double it. What capacitors, diodes and scheme I can use?
Tonic, Mon Feb 26 2007, 08:59PM
[quote]
I remember that I had a hard time measuring current. I ended up using a current shunt and a DVM some distance away from the circuit before the emf from the ZVS circuit would stop interfering with the DVM. I tried current clamps too.... no good. You might not be measuring the actual current and I can't see how a 100 watt transformer could but out that much power.
Use more batteries or a big transformer.
[/quote]
Hm.. EMF could interfered multimeter measuring, since it was near flyback.
Is it really impossible to get that much power? I don't have any batteries laying around. Probably the best option will be searching a cheap, used transformer from internet auction, I'll look around.
wrote ...
Try more capacitance on your resonant cap. Its easy and makes a big improvement in arc length.
Try more capacitance on your resonant cap. Its easy and makes a big improvement in arc length.
I've added something aroung 2.5uF and gained 3.5uF in total, but it didn't make different, or different was too small to notice. Or something is limiting.
By the way, I've changed primary wire to fatter one, ~1.5mm, but a heating problem still occurs. Do you have any idea how to solve it?
jmartis wrote ...
hi Tonic
do you use a limiting resistor on the output of the cascade? I tried a cascade with a limiting resistor, but it "sprays" heavily and lots of corona, and this decreases output. I'm afraid to run it without the limiting resistor, because I think it can be damaged from current surges.
hi Tonic
do you use a limiting resistor on the output of the cascade? I tried a cascade with a limiting resistor, but it "sprays" heavily and lots of corona, and this decreases output. I'm afraid to run it without the limiting resistor, because I think it can be damaged from current surges.
Are you saying about this type of cascade?
From
If yes, then no, I didn't use limiting resistor. I hadn't any reasons for this. You didn't want to damage cascade because of overcurrent? And you did use resitor on output, not input? Well, I don't get it ;)
It reminds how I plugged an cascade to flyback drivered by ZVS. Yeah, a bit stupid idea.. but, before cascade died by large current, it did shot a incredible, marvelous spark long at least 15cm and it was orange colour and quite fat. It really frightened me! What a pity I don't have pic of it ;( But I have an idea to connect TV cascades in parallel. Would it work?
Ambar wrote ...
I am mounting the ZVS to driver and I am with some you doubt on the functioning of it. For example, which is the maximum frequency that reaches. How many Watts is necessary so that of a hot arc?
I am mounting the ZVS to driver and I am with some you doubt on the functioning of it. For example, which is the maximum frequency that reaches. How many Watts is necessary so that of a hot arc?
If you are asking about frequencies at which ZVS driver works, I don't know, I'd rather shot that's something between 30-50 kHz.
To have that hot arc, it depends. Just make ZVS driver properly and get a power supply unit that can give at least 10A. Current is a main factory which decides how fat arc will be.
BTW, I'm re-asking - can anyone help with doubler? I have a 100W transformer with 1x24V AC output and I want to double it. What capacitors, diodes and scheme I can use?
Re: New fresh meat's toys and questions
Dr. Dark Current, Mon Feb 26 2007, 09:31PM
I will try it without the resistor, the cascade was free anyway so it doesn't matter if I destroy it
Dr. Dark Current, Mon Feb 26 2007, 09:31PM
Tonic wrote ...
Are you saying about this type of cascade?
From
If yes, then no, I didn't use limiting resistor. I hadn't any reasons for this. You didn't want to damage cascade because of overcurrent? And you did use resitor on output, not input? Well, I don't get it ;)
Yes, exactly this type. Somewhere on the site the picutre comes from, is also mentioned that the cascade should be never discharged directly to ground, but through a high-voltage resistor. The reason for this I think is that the spark to ground stresses the capacitors inside the cascade by a rapid discharge, which they'll never see in a TV, and can fail. The resistor then slows down the discharge. Are you saying about this type of cascade?
From
If yes, then no, I didn't use limiting resistor. I hadn't any reasons for this. You didn't want to damage cascade because of overcurrent? And you did use resitor on output, not input? Well, I don't get it ;)
I will try it without the resistor, the cascade was free anyway so it doesn't matter if I destroy it
Re: New fresh meat's toys and questions
..., Tue Feb 27 2007, 03:42AM
You need a resistor on the output of the cascade tp protect the internal diodes. Basically, if you do not have a resistor in series with the output the internal capacitors are discharged directly through the diodes into the load (which in the case of a TV has a very high impedeance, but for a spark it is very low), which can create very high peak currents; and diode diodes.
But if it works it works ;)
..., Tue Feb 27 2007, 03:42AM
You need a resistor on the output of the cascade tp protect the internal diodes. Basically, if you do not have a resistor in series with the output the internal capacitors are discharged directly through the diodes into the load (which in the case of a TV has a very high impedeance, but for a spark it is very low), which can create very high peak currents; and diode diodes.
But if it works it works ;)
Re: New fresh meat's toys and questions
Tonic, Sat Mar 03 2007, 11:57PM
Hey, acutally I'm trying to build half bridge for flyback and, probably, tesla coil, but it would be later. There are schemes I've drawn in according to different site pages and schemes (there were russian, czech, polish and american :P)
IR2153 driver
Power supply from main
And half bridge
There's small error in driver, the supply polarity is reversed.
Now, what do you think? I've choosen IR2153 because of simplity and effects that are shown on bottom of this page :
Tonic, Sat Mar 03 2007, 11:57PM
Hey, acutally I'm trying to build half bridge for flyback and, probably, tesla coil, but it would be later. There are schemes I've drawn in according to different site pages and schemes (there were russian, czech, polish and american :P)
IR2153 driver
Power supply from main
And half bridge
There's small error in driver, the supply polarity is reversed.
Now, what do you think? I've choosen IR2153 because of simplity and effects that are shown on bottom of this page :
Re: New fresh meat's toys and questions
Sulaiman, Sun Mar 04 2007, 08:22AM
International Rectifier give datasheets
and application notes for the IR2153, a good place to start.
Sulaiman, Sun Mar 04 2007, 08:22AM
International Rectifier give datasheets
and application notes for the IR2153, a good place to start.
Re: New fresh meat's toys and questions
Dr. Dark Current, Wed Mar 07 2007, 06:10PM
Dr. Dark Current, Wed Mar 07 2007, 06:10PM
Tonic wrote ...
Hey, acutally I'm trying to build half bridge for flyback and, probably, tesla coil, but it would be later. There are schemes I've drawn in according to different site pages and schemes (there were russian, czech, polish and american :P)
IR2153 driver
hmm.. i think you have a bad capacitors value. I have build this circuit previously ,and reffering to your schematic, I used 100nf for C3 and 2,2nf for C4.Hey, acutally I'm trying to build half bridge for flyback and, probably, tesla coil, but it would be later. There are schemes I've drawn in according to different site pages and schemes (there were russian, czech, polish and american :P)
IR2153 driver
Re: New fresh meat's toys and questions
Tonic, Thu Mar 08 2007, 08:25AM
jmartis, if it works for you, then I guess I'll listen to you, thanks ;)
Hm, I have problems with buying IR2153 or replacements, with exception of IR2155 which I found for 2 dollars, but at this time I was sure if I can use it. Now, after reading a datasheet, it seems that I could, since it's also a half-bridge driver. So, it's a true and can I use? If not, I will probably have to buy on online shop. Or use another driver - would you give any propositions? I'd like to use simple driver with popular parts, for example, with NE555. For start I don't need high frequencies, 50kHz sounds reasonable for me and I want to drive a half-bridge with IRFP450.
By the way, in weekend I was on bazaar and bought an russian 250W autotransformer with 200V to 270V regulation for 10$. Works nicely, with that I would supply 230V->24V transformer with higher voltage. So, in end I was able to power ZVS driver with 50V unload and 40V load. The results were impressive, I could stretch 11-14 cm arcs and the best things is that insulation doesn't work, even I've nice arcs. When there are no any arcs, I can see what a good insulation really means when secondaries arcs to themselves and core. A secondaries and cores killer, hehe. But, after insulating it properly and eventually adding third secondary I would probably get something around 20cm. In this way I should fight with Philer's record of arc length achieved on flybacks ;)
And, what insulation do you suggest for high voltage, with exeption of oil?
Tonic, Thu Mar 08 2007, 08:25AM
jmartis, if it works for you, then I guess I'll listen to you, thanks ;)
Hm, I have problems with buying IR2153 or replacements, with exception of IR2155 which I found for 2 dollars, but at this time I was sure if I can use it. Now, after reading a datasheet, it seems that I could, since it's also a half-bridge driver. So, it's a true and can I use? If not, I will probably have to buy on online shop. Or use another driver - would you give any propositions? I'd like to use simple driver with popular parts, for example, with NE555. For start I don't need high frequencies, 50kHz sounds reasonable for me and I want to drive a half-bridge with IRFP450.
By the way, in weekend I was on bazaar and bought an russian 250W autotransformer with 200V to 270V regulation for 10$. Works nicely, with that I would supply 230V->24V transformer with higher voltage. So, in end I was able to power ZVS driver with 50V unload and 40V load. The results were impressive, I could stretch 11-14 cm arcs and the best things is that insulation doesn't work, even I've nice arcs. When there are no any arcs, I can see what a good insulation really means when secondaries arcs to themselves and core. A secondaries and cores killer, hehe. But, after insulating it properly and eventually adding third secondary I would probably get something around 20cm. In this way I should fight with Philer's record of arc length achieved on flybacks ;)
And, what insulation do you suggest for high voltage, with exeption of oil?
Re: New fresh meat's toys and questions
Dr. Dark Current, Thu Mar 08 2007, 03:17PM
Dr. Dark Current, Thu Mar 08 2007, 03:17PM
Tonic wrote ...
Hm, I have problems with buying IR2153 or replacements, with exception of IR2155 which I found for 2 dollars, but at this time I was sure if I can use it. Now, after reading a datasheet, it seems that I could, since it's also a half-bridge driver. So, it's a true and can I use?
the IR2155 is an older version of IR2153, so yes, I think you can use it Hm, I have problems with buying IR2153 or replacements, with exception of IR2155 which I found for 2 dollars, but at this time I was sure if I can use it. Now, after reading a datasheet, it seems that I could, since it's also a half-bridge driver. So, it's a true and can I use?
Tonic wrote ...
And, what insulation do you suggest for high voltage, with exeption of oil?
For me, white candle wax works amazingly well for insulating HV stuff , but can be used only where temperature is not expected to rise too high And, what insulation do you suggest for high voltage, with exeption of oil?
Re: New fresh meat's toys and questions
ShawnLG, Thu Mar 08 2007, 03:54PM
"I will try it without the resistor, the cascade was free anyway so it doesn't matter if I destroy it"
It does matter. They don't make them anymore. I had one ten years ago and have not seen one since then.
ShawnLG, Thu Mar 08 2007, 03:54PM
"I will try it without the resistor, the cascade was free anyway so it doesn't matter if I destroy it"
It does matter. They don't make them anymore. I had one ten years ago and have not seen one since then.
Re: New fresh meat's toys and questions
Tonic, Sun Mar 11 2007, 12:00AM
Hmm.. according to charts included in IR2155's datasheet, before powering it, I should set variable resistor to max value, because it will set the lowest possible in this circuit frequency. Decreasing resistance will increase frequency. Am I right? I should finish the driver tomorrow (without IR2155), so I'm asking for surety ;)
Another question, on what value of half-bridge's power consumption depend?
Tonic, Sun Mar 11 2007, 12:00AM
jmartis wrote ...
the IR2155 is an older version of IR2153, so yes, I think you can use it
the IR2155 is an older version of IR2153, so yes, I think you can use it
Hmm.. according to charts included in IR2155's datasheet, before powering it, I should set variable resistor to max value, because it will set the lowest possible in this circuit frequency. Decreasing resistance will increase frequency. Am I right? I should finish the driver tomorrow (without IR2155), so I'm asking for surety ;)
Another question, on what value of half-bridge's power consumption depend?
Re: New fresh meat's toys and questions
Dr. Dark Current, Sun Mar 11 2007, 10:15AM
Maybe I should warn you about one thing: Every transformer (flybacks included) has its own resonant frequency (and its harmonics), where resonant rise occurs and the output voltage from the secondary is MANY TIMES the voltage when not in resonance, and also current draw increases dramatically. The voltage is usually enough to destroy your flyback in a fraction of second. Therefore I recommend at first power up to include some form of current limiting (a light bulb in series) and tune the circuit out of resonance (with least "idle" current draw), then you can remove it, but I usually put bigger bulbs in series before removing it completely, because it can also save your driver from exploding if something goes wrong.
Dr. Dark Current, Sun Mar 11 2007, 10:15AM
Tonic wrote ...
Hmm.. according to charts included in IR2155's datasheet, before powering it, I should set variable resistor to max value, because it will set the lowest possible in this circuit frequency. Decreasing resistance will increase frequency. Am I right? I should finish the driver tomorrow (without IR2155), so I'm asking for surety ;)
Yes, with decreasing resistance frequency increases, but I don't think it matters where you set it before powering upHmm.. according to charts included in IR2155's datasheet, before powering it, I should set variable resistor to max value, because it will set the lowest possible in this circuit frequency. Decreasing resistance will increase frequency. Am I right? I should finish the driver tomorrow (without IR2155), so I'm asking for surety ;)
Tonic wrote ...
Another question, on what value of half-bridge's power consumption depend?
This depends on many things, the main I think are supply voltage, number of primary turns and frequency.Another question, on what value of half-bridge's power consumption depend?
Maybe I should warn you about one thing: Every transformer (flybacks included) has its own resonant frequency (and its harmonics), where resonant rise occurs and the output voltage from the secondary is MANY TIMES the voltage when not in resonance, and also current draw increases dramatically. The voltage is usually enough to destroy your flyback in a fraction of second. Therefore I recommend at first power up to include some form of current limiting (a light bulb in series) and tune the circuit out of resonance (with least "idle" current draw), then you can remove it, but I usually put bigger bulbs in series before removing it completely, because it can also save your driver from exploding if something goes wrong.
Re: New fresh meat's toys and questions
Tonic, Sun Mar 11 2007, 01:26PM
Right, I was just thinking that higher frequency is, uglier output waveform is.
Too bad I don't have oscilloscope or any device for measuring frequency. That's the one of reason I've choosen IR2153/5, since they give without setting give two outputs which have square waveforms and one of them is horizontally 'flipped' and both of them have 50% cycle duty. That makes life simple, for me of course ;) But, if oscilloscope will be seriously needed, I may try with one in my school, but I can't guarantee that my teacher will allow to use.
BTW, I've prepared PCB and now it is taking an acid bath. The overall driver looks very cute for me, I'll try to shot photo as I get digital camera.
Tonic, Sun Mar 11 2007, 01:26PM
wrote ...
Yes, with decreasing resistance frequency increases, but I don't think it matters where you set it before powering up
Yes, with decreasing resistance frequency increases, but I don't think it matters where you set it before powering up
Right, I was just thinking that higher frequency is, uglier output waveform is.
wrote ...
Maybe I should warn you about one thing: Every transformer (flybacks included) has its own resonant frequency (and its harmonics), where resonant rise occurs and the output voltage from the secondary is MANY TIMES the voltage when not in resonance, and also current draw increases dramatically. The voltage is usually enough to destroy your flyback in a fraction of second. Therefore I recommend at first power up to include some form of current limiting (a light bulb in series) and tune the circuit out of resonance (with least "idle" current draw), then you can remove it, but I usually put bigger bulbs in series before removing it completely, because it can also save your driver from exploding if something goes wrong.
Maybe I should warn you about one thing: Every transformer (flybacks included) has its own resonant frequency (and its harmonics), where resonant rise occurs and the output voltage from the secondary is MANY TIMES the voltage when not in resonance, and also current draw increases dramatically. The voltage is usually enough to destroy your flyback in a fraction of second. Therefore I recommend at first power up to include some form of current limiting (a light bulb in series) and tune the circuit out of resonance (with least "idle" current draw), then you can remove it, but I usually put bigger bulbs in series before removing it completely, because it can also save your driver from exploding if something goes wrong.
Too bad I don't have oscilloscope or any device for measuring frequency. That's the one of reason I've choosen IR2153/5, since they give without setting give two outputs which have square waveforms and one of them is horizontally 'flipped' and both of them have 50% cycle duty. That makes life simple, for me of course ;) But, if oscilloscope will be seriously needed, I may try with one in my school, but I can't guarantee that my teacher will allow to use.
BTW, I've prepared PCB and now it is taking an acid bath. The overall driver looks very cute for me, I'll try to shot photo as I get digital camera.
Re: New fresh meat's toys and questions
Tonic, Sun Mar 25 2007, 09:32PM
Damn, I can't get this IR2155 driver to work. After playing with PCB version, I've decided to make simplier version. A small, fastly made PCB with 8pin IC socket, and I did in that way (see, I've tried it so many times and I can remember how I've soldered ;)) :
- ground connected to pin 4
- 1.5nF or 3.3nF (I can't read those weird names, there are only numbers) ceramic capacitor across pin 4 and pin 3
- 10Kohm resistor across pin 3 and pin 2
- plus to pin 1
- 1NF4007 diode across pin 1 and pin 8
- 1uF electrolytic capacitor across pin 8 and pin 6
- pin 7 -> 10ohm resistor -> upper MOSFET gate
- pin 5 -> 10ohm resistor -> down MOSFET gate
- pin 6 -> upper MOSFET's source and down MOSFET's drain -> primary winding
- upper MOSFET's drain to plus
- down MOSFET's source to minus
- two 1uF 275ACV X2 capacitors connected in series and parallel to plus and ground
- there where two capacitors are connected, it goes to primary winding
I hope you understond.. and found out if there's something wrong. What I have, is that when I plug driver to ~30DCV, there's no output of HV transformer, only IR2155 gets quite warm. I thought it was destroyed IR2155 from PCB version, so I replaced it with another and checked for while, but without results. I don't have oscilloscope, only cheap digital multimeter :P
Tonic, Sun Mar 25 2007, 09:32PM
Damn, I can't get this IR2155 driver to work. After playing with PCB version, I've decided to make simplier version. A small, fastly made PCB with 8pin IC socket, and I did in that way (see, I've tried it so many times and I can remember how I've soldered ;)) :
- ground connected to pin 4
- 1.5nF or 3.3nF (I can't read those weird names, there are only numbers) ceramic capacitor across pin 4 and pin 3
- 10Kohm resistor across pin 3 and pin 2
- plus to pin 1
- 1NF4007 diode across pin 1 and pin 8
- 1uF electrolytic capacitor across pin 8 and pin 6
- pin 7 -> 10ohm resistor -> upper MOSFET gate
- pin 5 -> 10ohm resistor -> down MOSFET gate
- pin 6 -> upper MOSFET's source and down MOSFET's drain -> primary winding
- upper MOSFET's drain to plus
- down MOSFET's source to minus
- two 1uF 275ACV X2 capacitors connected in series and parallel to plus and ground
- there where two capacitors are connected, it goes to primary winding
I hope you understond.. and found out if there's something wrong. What I have, is that when I plug driver to ~30DCV, there's no output of HV transformer, only IR2155 gets quite warm. I thought it was destroyed IR2155 from PCB version, so I replaced it with another and checked for while, but without results. I don't have oscilloscope, only cheap digital multimeter :P
Re: New fresh meat's toys and questions
Dr. Dark Current, Mon Mar 26 2007, 12:55PM
Hmm. Replace the diode with fast one (UF4007 works well). It also happened to me that I thought I have everything connected well and the driver did nothing, and then I found that I forgot a connection between lower fet's source and driver ic's ground!
If the ic gets warm, aren't you supplying it with too high voltage? It has an internal zener clamp to 14-16v so don't go above 14v.
Dr. Dark Current, Mon Mar 26 2007, 12:55PM
Hmm. Replace the diode with fast one (UF4007 works well). It also happened to me that I thought I have everything connected well and the driver did nothing, and then I found that I forgot a connection between lower fet's source and driver ic's ground!
If the ic gets warm, aren't you supplying it with too high voltage? It has an internal zener clamp to 14-16v so don't go above 14v.
Re: New fresh meat's toys and questions
Myke, Mon Mar 26 2007, 02:18PM
You should supply a seprate power source for the IC. If you are supplying ~30V and it clamps at ~14V then you are overvolting it by a lot.
Myke, Mon Mar 26 2007, 02:18PM
You should supply a seprate power source for the IC. If you are supplying ~30V and it clamps at ~14V then you are overvolting it by a lot.
Re: New fresh meat's toys and questions
Tonic, Wed Mar 28 2007, 07:52PM
Again, no luck.
I used PC's power supply and +12V, GND lines. At iddle driver with "integrated" IRF520 draws 0.25A, nothing heats after half minute and I don't see any output of HV transformer. I've noticed only that this current was increasing slowly to 0.40A before I powered off. The NF4007 diode was replaced with UF4007. I guess I did connected something wrong, or transistors/IR2155 just died. Capacitor is 1.5nF (finally I've learned how to read number. On this capacitor was mark 152. So 15pF*10^2 = 1500pF = 1.5nF).
How can I check, what's wrong? Especially those IR2155... they weren't cheap and it's quite rare in my town (not like as in Russia or Czech).
Tonic, Wed Mar 28 2007, 07:52PM
Again, no luck.
I used PC's power supply and +12V, GND lines. At iddle driver with "integrated" IRF520 draws 0.25A, nothing heats after half minute and I don't see any output of HV transformer. I've noticed only that this current was increasing slowly to 0.40A before I powered off. The NF4007 diode was replaced with UF4007. I guess I did connected something wrong, or transistors/IR2155 just died. Capacitor is 1.5nF (finally I've learned how to read number. On this capacitor was mark 152. So 15pF*10^2 = 1500pF = 1.5nF).
How can I check, what's wrong? Especially those IR2155... they weren't cheap and it's quite rare in my town (not like as in Russia or Czech).
Re: New fresh meat's toys and questions
Dr. Dark Current, Thu Mar 29 2007, 02:52PM
I checked your schematic again- oops! The connection from the upper FET's drain to Pin 8 of the ic certainly should NOT be there!!
And I found another error in your schematic, you have a missing connection between where the two FET's connect together (lower's drain - upper's source) and Pin 6 of the ic!
Hope you get it working now
edit- refer to this schematic
Dr. Dark Current, Thu Mar 29 2007, 02:52PM
I checked your schematic again- oops! The connection from the upper FET's drain to Pin 8 of the ic certainly should NOT be there!!
And I found another error in your schematic, you have a missing connection between where the two FET's connect together (lower's drain - upper's source) and Pin 6 of the ic!
Hope you get it working now
edit- refer to this schematic
Re: New fresh meat's toys and questions
Tonic, Thu Mar 29 2007, 04:09PM
I did solve this Pin 6 problem before. Now I've cut out upper FET's drain from Pin 8, but suddenly the iddle current drawing increased to ~7.5A and only both of MOSFETs are heating. IC, capacitor, resistors don't. No output, of course. I guess that's problem with oscillating, so probably IR2155 is just a dead one..
Tonic, Thu Mar 29 2007, 04:09PM
jmartis wrote ...
I checked your schematic again- oops! The connection from the upper FET's drain to Pin 8 of the ic certainly should NOT be there!!
And I found another error in your schematic, you have a missing connection between where the two FET's connect together (lower's drain - upper's source) and Pin 6 of the ic!
Hope you get it working now
edit- refer to this schematic
I checked your schematic again- oops! The connection from the upper FET's drain to Pin 8 of the ic certainly should NOT be there!!
And I found another error in your schematic, you have a missing connection between where the two FET's connect together (lower's drain - upper's source) and Pin 6 of the ic!
Hope you get it working now
edit- refer to this schematic
I did solve this Pin 6 problem before. Now I've cut out upper FET's drain from Pin 8, but suddenly the iddle current drawing increased to ~7.5A and only both of MOSFETs are heating. IC, capacitor, resistors don't. No output, of course. I guess that's problem with oscillating, so probably IR2155 is just a dead one..
Re: New fresh meat's toys and questions
Ambar, Wed Apr 04 2007, 12:53AM
Hi,
Small the frequency of zvs driver, bigger is HV of output? Huge primary turns, bigger current HV output?
Ambar, Wed Apr 04 2007, 12:53AM
Hi,
Small the frequency of zvs driver, bigger is HV of output? Huge primary turns, bigger current HV output?
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