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Re: Harmonic and intermodulation distortion and rms value
Hello Cristan,
You have two chances for your measurements. 1. Export the waveform data and analyze it with an external Math-program. File -> Export 2. Calculate with .measure. Below is an example for a THD calculation. The many SPICE-directives can reside in an extra file. Please take a look this example. Files > Tut > Measure > Tran > jfet_amp_disto_plot.zip You can apply the same method for IM, but then you will need a long simulation time proportional to 1/(f2-f1) for useful results Best regards, Helmut .measure Arms rms V(out) .measure Aavg avg V(out) ? .measure A2re avg? (V(out)-Aavg)*cos(360*time*Freq*2) .measure A2im avg (V(out)-Aavg)*sin(360*time*Freq*2) .measure K2 param 100*hypot(A2re,A2im)/Arms*sqrt(2) ? .measure A3re avg? (V(out)-Aavg)*cos(360*time*Freq*3) .measure A3im avg (V(out)-Aavg)*sin(360*time*Freq*3) .measure K3 param 100*hypot(A3re,A3im)/Arms*sqrt(2) ? .measure A4re avg? (V(out)-Aavg)*cos(360*time*Freq*4) .measure A4im avg (V(out)-Aavg)*sin(360*time*Freq*4) .measure K4 param 100*hypot(A4re,A4im)/Arms*sqrt(2) ? .measure A5re avg? (V(out)-Aavg)*cos(360*time*Freq*5) .measure A5im avg (V(out)-Aavg)*sin(360*time*Freq*5) .measure K5 param 100*hypot(A5re,A5im)/Arms*sqrt(2) ? .measure A6re avg? (V(out)-Aavg)*cos(360*time*Freq*6) .measure A6im avg (V(out)-Aavg)*sin(360*time*Freq*6) .measure K6 param 100*hypot(A6re,A6im)/Arms*sqrt(2) ? .measure A7re avg? (V(out)-Aavg)*cos(360*time*Freq*7) .measure A7im avg (V(out)-Aavg)*sin(360*time*Freq*7) .measure K7 param 100*hypot(A7re,A7im)/Arms*sqrt(2) ? .measure A8re avg? (V(out)-Aavg)*cos(360*time*Freq*8) .measure A8im avg (V(out)-Aavg)*sin(360*time*Freq*8) .measure K8 param 100*hypot(A8re,A8im)/Arms*sqrt(2) ? .measure A9re avg? (V(out)-Aavg)*cos(360*time*Freq*9) .measure A9im avg (V(out)-Aavg)*sin(360*time*Freq*9) .measure K9 param 100*hypot(A9re,A9im)/Arms*sqrt(2) .measure thd param sqrt(K2*K2+K3*K3+K4*K4+K5*K5+K6*K6+K7*K7+K8*K8+K9*K9) |
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Re: High Voltage Thryotron/Thyresistor?
Not one to speculate but give a few references here you are
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Reference 1 Along with a description of "what it does" Stanford uses these apparently in their accelerator these days. also a stanford paper discussing this (2000 ish) www.slac.stanford.edu/pubs/slacpubs/8250/slac-pub-8475.pdf CERN paper of university of Edinburgh, (2006) accelconf.web.cern.ch/AccelConf/e06/PAPERS/WEPCH192.PDF It's doable, and it's done that doesn't mean it's easy to do, however it is doable. If the OP plans on a something "low" power then stacking the IGBT's isn't necessary, 3KV for the exciter should be enough and you can make a boost regulator for getting sufficient voltage. Even 1700V or 2400V parts for 1200V and 2000V systems would work. The parts get more exotic and expensive however you only need a few parts for driving it (they make bridge drivers for that voltage range). CREE makes some Silicon Carbide parts in that range (). A few hundred watts (IE < 500W) you can get away with 120VAC but you do need to make an interesting boost convertor. These parts are obtainable at digikey and mouser you can also test things (except maybe the driver) unfortunately getting a high side driver for a bridge configuration could get interesting if you wanted to drive the system that way, most of the bootstrap IC's stop at 600V (likely designed for 480VAC operation). Anyhow you can model the thing in ltspice although the transformer on the primary might be interesting too model (hmmm). Hopefully this is helpful to your plans. Stephen R. Phillips was here Please be advised what was said may be absolutely wrong, and hereby this disclaimer follows.??I reserve the right to be wrong and admit I was wrong in front of the entire world. It won't be the first or the last in all likelyness. On Tuesday, June 3, 2014 1:58 AM, "sawreyrw@... [LTspice]" <LTspice@...> wrote:
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Harmonic and intermodulation distortion and rms value
Regards Cristian |
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Re: High Voltage Thryotron/Thyresistor?
Yea, the current pulse is CRAZY when one dumps a cap charged at 3kV into another cap. ?I think it those would be blown to smithereens in this application. ?I could be wrong. Chris KQ6UP
On Mon, Jun 2, 2014 at 8:23 PM, miller_effect@... [LTspice] <LTspice@...> wrote:
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Re: problem of encrypt model LM3150
Not that it matters, but your schematic also has the wrong parameters (attributes) for the LM3150 device. ?The first listed parameter ("LM3150_tina.sub") should be the name of the subcircuit being called; not a file name.
Your schematic also needs to .INCLUDE the model file. You could combine the name of the model file in the symbol, by listing it in the "ModelFile" attribute of the .ASY symbol file.
?Andy? |
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Re: High Voltage Thryotron/Thyresistor?
That does sound intriguing. I am just thinking that a couple hundred
watts would be fine. I could just find the time constant where ringing the primary tank just dies out, then -- bam! Dump another capacitor charge into the tank to ring it again, or generate a square wave at the resonant frequency of the tank circuit. Chris KQ6UP On Mon, Jun 2, 2014 at 6:13 PM, Stephen R Phillips cyberman_phillips@... [LTspice] <LTspice@...> wrote: You can use stacked IGBT's much the same way with easier / simpler control, you do need drivers for them and thus you probably should do some analysis. You can get spice models for IGBT's for ltspice, and you can model individual stage power supplies by using optocouplers and 1G resistors (IE theoretrical isolation but still have convergence because it can find a resistor to ground heh). |
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problem of encrypt model LM3150
Dear All, I had an issue to import the encrypt model LM3150 to ltspice, I uploaded the file:LM3150.zip contains models, symbol and test circuit to the temp folder, look for your kindness to help me on this subject..? I learned from The model creator-Texas instrument that this model can be run on?in PSPICE 15 .7 or higher, if this help? Regards, ?? |
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Re: High Voltage Thryotron/Thyresistor?
You can use stacked IGBT's much the same way with easier / simpler control, you do need drivers for them and thus you probably should do some analysis. You can get spice models for IGBT's for ltspice, and you can model individual stage power supplies by using optocouplers and 1G resistors (IE theoretrical isolation but still have convergence because it can find a resistor to ground heh).
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Panasonic uses IGBTs to drive the magnetron in some of their microwaves, (PWM a magnetron to get variable power output I won't comment as to why they would do that as it gets into some things I barely understand in electronmagnetic theory). Erstwhile they also use IGBTs stacked for driving particle accelerators (syncotrons) so yes you can use them to drive something at a very high voltage. IXYS makes IGBT's that go up to 4500V (which means you probably could safely use them at 3KV with per layer if being conservative). That may be high enough to drive the excitation coil for? what you want to do. Making a boost supply for it would prove to be a lot of work but possible. What power level are you talking here? 1kw 2kw 4kw 8kw 16kw 32kw? 2kw and above is 240vac 4kw 240VAC 3phase You might consider 480VAC 3phase above 8kw Stephen R. Phillips was here Please be advised what was said may be absolutely wrong, and hereby this disclaimer follows.??I reserve the right to be wrong and admit I was wrong in front of the entire world. It won't be the first or the last in all likelyness. On Monday, June 2, 2014 9:41 PM, "marcelhendrix25@... [LTspice]" <LTspice@...> wrote:
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Re: High Voltage Thryotron/Thyresistor?
¿ªÔÆÌåÓýIf you want some real kudos then show your students this though you might have to explain who King Crimson are J In the Hall of the Mountain King played on a pair of Tesla coils. ? ? Suusi ? From: LTspice@... [mailto:LTspice@...]
Sent: 02 June 2014 19:36 To: LTspice@... Subject: Re: [LTspice] Re: High Voltage Thryotron/Thyresistor? ? Maybe 4 in series dumping a cap from a relaxation oscillator into a LC network for a primary LC tank circuit for a Tesla coil. ?At 4kV I could use a microwave oven transformer and make one hellofa tesla coil on the cheap. ?It would also be quieter. ?My students built a traditional Tesla coil for extra credit, and I did not realize how loud the spark gap is. ?It is DEAFENING.? ? Thanks, Chris Maness ? On Mon, Jun 2, 2014 at 11:23 AM, 'Suusi M-B' smalcolmbrown@... [LTspice] <LTspice@...> wrote: ? I have done some playing with LTspice and radar psu¡¯s and transmitters. ? Forget a model of a thyratron I know of none out there. ? As for a SCR the SK065K seems to fit the bill ? ? That said I have been toying with the idea of a using an IRF830 Hexfet as the trigger device ? ? Best regards ? Suusi M-B ? ? ? ? ? From: LTspice@... [mailto:LTspice@...] ? Haha, yes. ?Spelling notwithstanding :D ? Chris ? On Mon, Jun 2, 2014 at 10:12 AM, miller_effect@... [LTspice] <LTspice@...> wrote:
? ME ? ? ? ? |
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Re: High Voltage Thryotron/Thyresistor?
Maybe 4 in series dumping a cap from a relaxation oscillator into a LC network for a primary LC tank circuit for a Tesla coil. ?At 4kV I could use a microwave oven transformer and make one hellofa tesla coil on the cheap. ?It would also be quieter. ?My students built a traditional Tesla coil for extra credit, and I did not realize how loud the spark gap is. ?It is DEAFENING.? Thanks, Chris Maness On Mon, Jun 2, 2014 at 11:23 AM, 'Suusi M-B' smalcolmbrown@... [LTspice] <LTspice@...> wrote:
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Re: High Voltage Thryotron/Thyresistor?
¿ªÔÆÌåÓýI have done some playing with LTspice and radar psu¡¯s and transmitters. ? Forget a model of a thyratron I know of none out there. ? As for a SCR the SK065K seems to fit the bill ? ? That said I have been toying with the idea of a using an IRF830 Hexfet as the trigger device ? ? Best regards ? Suusi M-B ? ? ? ? ? From: LTspice@... [mailto:LTspice@...]
Sent: 02 June 2014 18:36 To: LTspice@... Subject: Re: [LTspice] Re: High Voltage Thryotron/Thyresistor? ? Haha, yes. ?Spelling notwithstanding :D ? Chris ? On Mon, Jun 2, 2014 at 10:12 AM, miller_effect@... [LTspice] <LTspice@...> wrote:
? ME ? ? |
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Re: High Voltage Thryotron/Thyresistor?
Haha, yes. ?Spelling notwithstanding :D Chris On Mon, Jun 2, 2014 at 10:12 AM, miller_effect@... [LTspice] <LTspice@...> wrote:
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