1st decent DRSSTC
mmt, Sun Jul 31 2011, 11:37AMHi, after getting familiar with IGBT bricks and UD1.3 here is my medium sized DRSSTC
specs:
sec: 19.3x6.3 30 AWG
topload: 22.4x4.7 + 10.6x1.7
tank cap: 0.3uF/3,6kVDC
f0: 65-85kHz
power electronics: BSM75GB120DN2 haflbridge, voltage doubler to 600VDC with 2x3300uF
driver: Steve Ward's UD1.3
best spark: 74.8" limmited at 490A (i'm affraid to set more..)
thanks goes to Goodchild for some advices
Re: 1st decent DRSSTC
StevenCaton, Sun Jul 31 2011, 06:09PM
That looks great. Nice job.
StevenCaton, Sun Jul 31 2011, 06:09PM
That looks great. Nice job.
Re: 1st decent DRSSTC
Goodchild, Sun Jul 31 2011, 08:29PM
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
Goodchild, Sun Jul 31 2011, 08:29PM
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
Re: 1st decent DRSSTC
Gregory, Sun Jul 31 2011, 09:53PM
Beautiful setup, nice results!
What are your pulse width? Maybe you can set the OCD to 550A..
Gregory, Sun Jul 31 2011, 09:53PM
Beautiful setup, nice results!
What are your pulse width? Maybe you can set the OCD to 550A..
Re: 1st decent DRSSTC
StevenCaton, Sun Jul 31 2011, 10:06PM
When in doubt, always set the OCD higher.
StevenCaton, Sun Jul 31 2011, 10:06PM
(i'm affraid to set more..)
When in doubt, always set the OCD higher.
Re: 1st decent DRSSTC
Mads Barnkob, Mon Aug 01 2011, 06:59AM
Good job on your drsstc :) I still think you can gain longer sparks from fine tuning, the sweet spot is with a few centimeters when moving the primary tap around, you can miss it many times while experimenting :)
The high impedance system might only apply to larger systems.
Considering he runs this at 600V / 490A with 187 cm sparks.
My low impedance coil at 320V / 500A gave 150 cm sparks.
I would attribute the higher voltage for the success
Mads Barnkob, Mon Aug 01 2011, 06:59AM
Good job on your drsstc :) I still think you can gain longer sparks from fine tuning, the sweet spot is with a few centimeters when moving the primary tap around, you can miss it many times while experimenting :)
Goodchild wrote ...
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
The high impedance system might only apply to larger systems.
Considering he runs this at 600V / 490A with 187 cm sparks.
My low impedance coil at 320V / 500A gave 150 cm sparks.
I would attribute the higher voltage for the success
Re: 1st decent DRSSTC
Goodchild, Mon Aug 01 2011, 08:05AM
Higher bus voltage defiantly played it's part here good you pointed that out I missed how high it really was, but don't discredit high impedance for only large systems! Take a look at the QCW it's about as small as it gets and even with a low bus voltage (380VDC) can still manage 5+ feet with only 100A of primary current. It's all about overall power and how you apply it
One other thing to keep in mind is secondary size, as that plays a large role in spark length as well.
mmt what is the tank impedance of your system? I'm twitching with curiosity to know now hehe
Goodchild, Mon Aug 01 2011, 08:05AM
Mads Barnkob wrote ...
Good job on your drsstc :) I still think you can gain longer sparks from fine tuning, the sweet spot is with a few centimeters when moving the primary tap around, you can miss it many times while experimenting :)
The high impedance system might only apply to larger systems.
Considering he runs this at 600V / 490A with 187 cm sparks.
My low impedance coil at 320V / 500A gave 150 cm sparks.
I would attribute the higher voltage for the success
Good job on your drsstc :) I still think you can gain longer sparks from fine tuning, the sweet spot is with a few centimeters when moving the primary tap around, you can miss it many times while experimenting :)
Goodchild wrote ...
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
The high impedance system might only apply to larger systems.
Considering he runs this at 600V / 490A with 187 cm sparks.
My low impedance coil at 320V / 500A gave 150 cm sparks.
I would attribute the higher voltage for the success
Higher bus voltage defiantly played it's part here good you pointed that out I missed how high it really was, but don't discredit high impedance for only large systems! Take a look at the QCW it's about as small as it gets and even with a low bus voltage (380VDC) can still manage 5+ feet with only 100A of primary current. It's all about overall power and how you apply it
One other thing to keep in mind is secondary size, as that plays a large role in spark length as well.
mmt what is the tank impedance of your system? I'm twitching with curiosity to know now hehe
Re: 1st decent DRSSTC
Mads Barnkob, Mon Aug 01 2011, 09:03AM
I agree with all you say, but lets keep to comparing this one topology :)
The MMC could make a difference to a standard 940/942C one. Its standard MKP capacitors and about half the capacitance of mine.
Mmt, How many turns did you tap your primary coil at? I can't see the lead on the pictures...
Mads Barnkob, Mon Aug 01 2011, 09:03AM
Goodchild wrote ...
Higher bus voltage defiantly played it's part here good you pointed that out I missed how high it really was, but don't discredit high impedance for only large systems! Take a look at the QCW it's about as small as it gets and even with a low bus voltage (380VDC) can still manage 5+ feet with only 100A of primary current. It's all about overall power and how you apply it
One other thing to keep in mind is secondary size, as that plays a large role in spark length as well.
mmt what is the tank impedance of your system? I'm twitching with curiosity to know now hehe
Mads Barnkob wrote ...
Good job on your drsstc :) I still think you can gain longer sparks from fine tuning, the sweet spot is with a few centimeters when moving the primary tap around, you can miss it many times while experimenting :)
The high impedance system might only apply to larger systems.
Considering he runs this at 600V / 490A with 187 cm sparks.
My low impedance coil at 320V / 500A gave 150 cm sparks.
I would attribute the higher voltage for the success
Good job on your drsstc :) I still think you can gain longer sparks from fine tuning, the sweet spot is with a few centimeters when moving the primary tap around, you can miss it many times while experimenting :)
Goodchild wrote ...
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
Fancy, getting some nice sparks I see. I guess you went with a high impedance system by the looks of your peak current compared to your spark length.
Looks great keep up the good work.
The high impedance system might only apply to larger systems.
Considering he runs this at 600V / 490A with 187 cm sparks.
My low impedance coil at 320V / 500A gave 150 cm sparks.
I would attribute the higher voltage for the success
Higher bus voltage defiantly played it's part here good you pointed that out I missed how high it really was, but don't discredit high impedance for only large systems! Take a look at the QCW it's about as small as it gets and even with a low bus voltage (380VDC) can still manage 5+ feet with only 100A of primary current. It's all about overall power and how you apply it
One other thing to keep in mind is secondary size, as that plays a large role in spark length as well.
mmt what is the tank impedance of your system? I'm twitching with curiosity to know now hehe
I agree with all you say, but lets keep to comparing this one topology :)
The MMC could make a difference to a standard 940/942C one. Its standard MKP capacitors and about half the capacitance of mine.
Mmt, How many turns did you tap your primary coil at? I can't see the lead on the pictures...
Re: 1st decent DRSSTC
Arcstarter, Mon Aug 01 2011, 09:03PM
Well, more primary cycles will always increase spark length regardless of the overall impedance. With a high impedance system you would need to run more primary cycles to overcome the loss of spark length due to the lower current. Steve Ward ran as much as 14ms on at some 100 amps of primary current with his QCW drsstc (i know you said keep comparing to one topology, but the only difference between the QCW other than high impedance is buss voltage control). It is just a compromise between many different factors.
Great coil! A single 105 amp brick with 75 inch sparks . As for the current, i have run a slower 75 amp 600v brick at 600 amps without a problem, but it eventually blew do to some hardcore ringing due to a pretty bad phase shift due to their speed. I was using a heatsink similar to yours without a fan. It did get warm, but not hot. However, whether or not you raise current is your decision, i don't want to be responsible for a dead IGBT!
Arcstarter, Mon Aug 01 2011, 09:03PM
Well, more primary cycles will always increase spark length regardless of the overall impedance. With a high impedance system you would need to run more primary cycles to overcome the loss of spark length due to the lower current. Steve Ward ran as much as 14ms on at some 100 amps of primary current with his QCW drsstc (i know you said keep comparing to one topology, but the only difference between the QCW other than high impedance is buss voltage control). It is just a compromise between many different factors.
Great coil! A single 105 amp brick with 75 inch sparks
. As for the current, i have run a slower 75 amp 600v brick at 600 amps without a problem, but it eventually blew do to some hardcore ringing due to a pretty bad phase shift due to their speed. I was using a heatsink similar to yours without a fan. It did get warm, but not hot. However, whether or not you raise current is your decision, i don't want to be responsible for a dead IGBT!Re: 1st decent DRSSTC
mmt, Tue Aug 02 2011, 10:21AM
Hi guys, thx for the positive reply :)
I'm just a beginner with these systems i've never wonder about the impedance, i dont have a Z meter, but if you tell me how to measure it with basic tools i measure it for you. My primary is tappet exactly at 8 turn.
mmt, Tue Aug 02 2011, 10:21AM
Hi guys, thx for the positive reply :)
I'm just a beginner with these systems i've never wonder about the impedance, i dont have a Z meter, but if you tell me how to measure it with basic tools i measure it for you. My primary is tappet exactly at 8 turn.
Re: 1st decent DRSSTC
Gregory, Tue Aug 02 2011, 07:25PM
The LC tank impedance is sqrt(L/C)
Gregory, Tue Aug 02 2011, 07:25PM
The LC tank impedance is sqrt(L/C)
Re: 1st decent DRSSTC
mmt, Wed Aug 03 2011, 07:36PM
9,16ohm
mmt, Wed Aug 03 2011, 07:36PM
9,16ohm
Re: 1st decent DRSSTC
Gregory, Thu Aug 04 2011, 12:43AM
Its a medium to high impedance tank, vary good results! What is your pulse width?
Gregory, Thu Aug 04 2011, 12:43AM
Its a medium to high impedance tank, vary good results! What is your pulse width?
Re: 1st decent DRSSTC
mmt, Thu Aug 04 2011, 04:50PM
by PW i adjust 'power' according Steve's interrupter with burst mode, so it's on its maximum, and BPS is 125-130
mmt, Thu Aug 04 2011, 04:50PM
by PW i adjust 'power' according Steve's interrupter with burst mode, so it's on its maximum, and BPS is 125-130
Re: 1st decent DRSSTC
Mads Barnkob, Tue Aug 09 2011, 07:47PM
Would you mind putting all your numbers and coil data into JavaTC and post a screenshot of the results?
Mads Barnkob, Tue Aug 09 2011, 07:47PM
Would you mind putting all your numbers and coil data into JavaTC and post a screenshot of the results?
Re: 1st decent DRSSTC
Polonium210, Mon Aug 22 2011, 01:35AM
Very nice work. Can I ask what capacitors you are using for your MMC? Could you share the part number?
Polonium210, Mon Aug 22 2011, 01:35AM
Very nice work. Can I ask what capacitors you are using for your MMC? Could you share the part number?
Re: 1st decent DRSSTC
mmt, Wed Aug 24 2011, 11:12AM
I've used Tesla TC343 82n/1500V caps, those are really old but high quality and i they don't manufacture anymore i guess. Tesla is an old electronic company wich exists in CzechoSlovakia about 25 years ago. Now its ES Ostrava
mmt, Wed Aug 24 2011, 11:12AM
I've used Tesla TC343 82n/1500V caps, those are really old but high quality and i they don't manufacture anymore i guess. Tesla is an old electronic company wich exists in CzechoSlovakia about 25 years ago. Now its ES Ostrava
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