Forward EMF Collection

[d3x0r]

just a sim of another another akula device... http://www.overunity.com/14610/akula0083-light-no3-dual-tl494/#.U3WNnPldV48 (start of thread)

[d3x0r]

New Simulator; forward, backward and inside out EMF


Falstad Simulator


Two switches, one coil  (heh that should be a website)


There's a diode and a cap; The 10uF cap is the target for 'power'.  How much this fills is how much 'spike' EMF causes.  For the rest of this 'tis is 'the cap'. 
I added seriels coil resistance and parallel coil capacitance for its wire so the simulation wouldn't just crash.  I added parallel 10pF capacitance on the switches. 


I dunno I had wondered at one point whether the side the power was on vs the side the switch was on would matter.


The first image is the highest voltages on the cap are shown, and which switch was toggled to get that.


Toggled means I reset the sim, (image 2)
and then closed and opened the switch that is open in image 1; the result of which is image 1...




So one may see a 'high voltage' spike and consider that is what the result to capture is.. but really that voltage is a result of the spring-back... the coil runs into the open switch, fills up the tinycapacitance, which reflects back to the coil....  It's not until the coil is entirely stopped that it can start spinning in the opposite direction... and that entire time it's stopping is what you really want to catch, not what was stored in the capacitance as it hit the wall (the spring absobing impact that returns)


Forward EMF is the 'a body in motion wants to stay in motion' which is why a choke works, because as the current decreases or increases slightly, it's balanced to what the average is ... if a minor change in current caused immediate currrent reversal it'd be a train wreck all over....


I dunno; To use the sim, close both switches, and open one... the resulting effect is not the same.

[d3x0r]

Simplified circuit...
Falstad sim...


you can collect either positive or negative delta... one is an extra loss because it goes through resistances twice...