| Author |
 Topic  |
|
|
Trait
New Member
USA
39 Posts |
 Posted - 03/09/2009 : 09:32:05 AM
|
Hey guys,
Just a quick update on my latest project.
I've combined the ideas behind a joule thief and a Bedini Charge to cut down on my project costs. (I have serious personal issues with poor quality parts but can't do machining) LOL
SO, I've found an old 120V to 480V transformer and have run my trigger through the low voltage side and through a 10k to 20k ohm pot for timing.
I run my power through the high voltage side and to the collector, I pull BEMF off the collector just like in a bedini.
So far, I've seen 160 volt spikes on BEMF while pulling 4 miliamps.
This is all powered by 4 Double A cell batteries.
Thanks for listening guys, I'll post pics later.
Aaron
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 06/09/2009 : 2:38:55 PM
|
Just another quick update guys.
The transformer I used was an Acme TA-1-81217.
Running 4 AA cell batteries in series (from some Solar garden lights I tore apart for the cells).
I've gotten the best spikes at just a hair over 4 mills (spikes up to about 170 volts.)
I'm going to charge another 4 AA's in series to see what kind of results I get.
The trigger Ohms are about 15k - 20k range plus transformer low side windings. |
 |
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 11/09/2009 : 11:43:39 AM
|
indeed, transformer coils can be increadibly efficient in this manner...
I'm sortof playing with something similar...
----------------------------------------------------------------------------------------------------------
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 12/09/2009 : 12:34:48 PM
|
Hey Comwarrior,
I'm glad I'm not the only one playing with this setup.
My biggest hurdle and ultimate goal would be to chop the transistor at the PEAK of voltage inrush.
Sadly I don't have the know how to do this yet. Everything I've done up to this point has been trial and error with a few brief reads on beginner electronics.
Do you have any ideas on clipping the drive power on peak voltage before current rises?
I think Tesla performed experiments with rapid fire DC using many mechanical contacts but I don't have the resources for that.
Thanks in advance!
Aaron |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 12/09/2009 : 5:17:00 PM
|
I may have answered my own question.
After posting I scoured the internet and came up with a rough plan.
I think I'll swap from an NPN transistor to a PNP and shift things around.
I'll use the low voltage side of the transistor to trigger the base and place a low pf cap in series along with a pot for timing.
SO, when the unit is powered on, the low voltage at the base will trigger the transistor allowing flow.
Flow through the transformer will produce + voltage on the trigger shutting the unit down.
Once the BEMF event is over and the transformer is at rest, the transistor triggers again starting the cycle over again.
I've got high hopes the system will use considerably less ma and run higher voltage spikes.
Thanks for listening guys!
-Trait- |
|
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 12/09/2009 : 6:44:50 PM
|
[Smiles and says...]
I was thinking of using the PWM on a micro controler... that way not only can i read 8 analogue voltages but i've also got controll over the PWM frequencies from 2 KHz and up and the duty cycle too...
[smiles] ...yes i have one on the board...
----------------------------------------------------------------------------------------------------------
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 12/09/2009 : 6:56:44 PM
|
If you run any tests, I'd love to hear what you find.
I have a sneaky suspicion Ma will drop ALOT.
Talk to ya soon,
-Trait- |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 12/09/2009 : 7:11:57 PM
|
What are you using as a controller? Is it like a micro controller by Allen bradley or siemens?
I've got experience with ladder logic so I'm just curious what you're using to program.
I could easily see a comparison of last scan's voltage and killing the transistor when voltage is lower than last scan *Grins* |
|
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 12/09/2009 : 8:00:40 PM
|
ok, well, you'll be the first to be told what i'm using... your privilidged... lol
I'm using PIC micro controllers...
Spacifically, I like the PIC16F877A's 20MHz input clock, twin PWM's, 8 ADC's, SPI, 1 Wire, I2C, PSP, 3 timer/counters...
To program, you can use ether assembler, C or as i'm using PICBASIC...
You can get microchips own IDE free at their website... http://www.microchip.com
----------------------------------------------------------------------------------------------------------
Generator Systems Moderator
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
"Every Action has an equal and opposite re-action" - Why not use the re-action to create an additional action?
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
Edited by - comwarrior on 12/09/2009 8:05:17 PM |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 13/09/2009 : 11:08:40 AM
|
As long as I can avoid frying something like this, I could certainly find a ton of uses for a programmable controller!
Thanks for sharing the info! I'm going to see what I can find and get some prices 8)
-Trait- |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 13/09/2009 : 1:56:10 PM
|
Hey CW,
I had a thought and since you're using controllers you may have some valuable feedback on it.
I'm looking at http://arduino.cc/en/Reference/AnalogReference
And it looks like I have an analog input that compares to a reference voltage. So my thought is, to place a small cap on the reference voltage from the trigger coil and the voltage to the analog input.
My thought is it will see 100% voltage until the voltage spike turns, when that happens I can have the controller kill the transistor.
What do ya think? |
|
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 13/09/2009 : 4:09:25 PM
|
ok, first off... my 16F877A has been exposed directly to a 16mm N42 magnet at point blank...
it's ouput pins have been shorted when live...
it's been exposed to +12V on on input pin (supposed to be +5V)...
It's had it's 5V supply reversed...
it's been exposed directly to back EMF...
I've dropped it in a cup of fresh very hot coffee...
I tried programming it in it's programmer the wrong way around...
The only thing i know of that does actually kill them is a 500MF capacitor charged with 180 volts... oops!
Or a hammer...
----------------------------------------------------------------------------------------------------------
Generator Systems Moderator
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
"Every Action has an equal and opposite re-action" - Why not use the re-action to create an additional action?
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 13/09/2009 : 4:47:35 PM
|
That's good news CW.
I have NO experience with those chips you use, but that link I posted seems to be similar and affordable so I may go that route. (I can certainly work with a pre assembled unit, but creating one may be next year's project...They ARE much cheaper than I expected!)
I'm also considering a voltage divider to check the spike state. (I'm still a bit worried about the spikes to the input... I'm getting spikes of about 260 VDC at 40 ma. This seems like alot for that poor little A input to handle.)
I can average the last 10 scans and when the TriggerIn < TriggerAvg I can safely say that the spike is over and cut power to the transistor.
And... A Hammer??? LOL |
|
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 13/09/2009 : 6:17:11 PM
|
the 16F877A is about £5... and certainly affordable...
Don't ask about the hammer... you don't want to know... it's too painfull...
The 877A has an internal ref of 5 volts but even so, my trigger coil goes over this... but the 877A has built in protection if a pin goes over the supply voltage... and yes, you can use an external ref...
You don't want to be sampling that high a voltage directly, you will kill any chip... so, yes a voltage divider is good...
One thing i havn't mentioned ANYWHERE yet is that i've atached an LCD to my PIC... so i get a direct RPM readout on the LCD... but thats not all it's going to readout...
I'm also writing a program to automatically tune the settings... Theirs 4 setting it uses, 2 are just backup/aux settings but we have... Turn on voltage, Turn on overide delay(aux), Turn off coltage and turn off overide delay(aux).
The AUX setting prevent the chip from making the coil self osc at over 20 KHz (outside normal hearing range)...
I'm also writing an RPM safegaurd so if the RPM goes over what i deem 'safe' then it will not pulse...
Also doing a Voltage safegaurd, if the 12V goes above 15 volts then it'll turn on a 12volt bulb to dump power...
I'm very much tempted to order a couple of other chips too... Since i don't have an osciliscope, i was thinking of programming a chip with the sole function of reading the ADC as fast as it can go and 'displaying' a wave form...
Theirs lots you can do with a micro controler...
----------------------------------------------------------------------------------------------------------
Generator Systems Moderator
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
"Every Action has an equal and opposite re-action" - Why not use the re-action to create an additional action?
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 13/09/2009 : 6:36:16 PM
|
I like the ideas!
I was thinking of using one of those AI points to read MA being used by the system and decrease trigger to trim power usage down. Or do like you said and use the AOut to trigger, the AIn to read system Ma and tune for best spikes based on Lowest Ma/High voltage spikes. After that you could begin charging and based on the ramp rate you could increase frequency first then trigger voltage.
The nice thing about solid state is that things won't fly apart ^^
I'm really looking forward to moving towards controlled experiments. I think a micro controller's just what I needed! Thanks for steering me that direction! |
|
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 13/09/2009 : 8:45:46 PM
|
Anyone thats used BASIC befor... IE with spectrums, commodors, amigas etc etc... will be able to write programs for a PIC...
Most of the hard work has allready been done for you...
For example, to send "hello" to an LCD the command is simple...
LCDOUT $FE, "hello"
To send "hello" up a software serial port...
SEROUT2 PORTB.7,16390,["hello", 10,13]
The send "hello" up a hardware serial port...
HSEROUT ["hello",10,13]
To configure the PWM...
HPWM 0,127,10000
HPWM 1,127,10000
after that it's all IF's, ELSEs, GOSUB's and GOTO's...
Oh, don't forget the ADC's...
ADCIN 0, ADCVAL1
and digital controls...
LOW portb.0
HIGH portb.0
And thats it... unless you want to use I2C, 1wire and PSP data busses for multi-device high speed communications...
LOL
----------------------------------------------------------------------------------------------------------
Generator Systems Moderator
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
"Every Action has an equal and opposite re-action" - Why not use the re-action to create an additional action?
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
|
|
|
Trait
New Member
USA
39 Posts |
Posted - 14/09/2009 : 08:36:31 AM
|
I took a look at the code for these Arduino boards and was pleasantly supprised. I code in C# and Autoit and the language isn't all that different.
I'm hoping that once I get the board, I can go right to coding! |
|
|
|
comwarrior
Moderator
United Kingdom
477 Posts |
Posted - 15/09/2009 : 10:48:12 AM
|
indeed... ASP, PHP, C , Basic, Java script etc etc all have similar syntax's... a lot of the same 'comands' are allmost the same... raises the point as to why whe have so many diferent languages... but then again, ASP is microsoft 'owned' so, you'll have the microsoft way and then you'll have the way the true Pro's do it... Without microsoft...
----------------------------------------------------------------------------------------------------------
Generator Systems Moderator
"Energy can not be created nor distroyed, it can only be changed into other forms" - so lets do some changing!
"Every Action has an equal and opposite re-action" - Why not use the re-action to create an additional action?
95% efficiency, I dare you to do better!
http://www.youtube.com/user/comwarrior69 |
|
|
| |
Topic |
|
Solid state charger
