Round a hundred bucks for something that can handle ~500AYou may not realize this, but finding H-bridge drivers that will work at 1.2kv isn't trivial, and they won't be cheap. Most of them run out of that proverbial steam by 600v.
This thread should be closed immediately. The OP is clearly confused over basic concepts, is pursuing a perpetual motion machine, and despite his assertions of attention to proper safety measures, is planning to build something hugely dangerous....the unit is self powered from then on for as long the batteries continue to take a charge.
There is absolutely no motion to this machine what-so-ever so perpetual motion is a ridiculous statement and your a senior member? What a retard! I had a question on how to reverse polarity on a HV electromagnet and was doing just fine conversing with SGT. Wookie it has blossomed into a discussion of the device I am building and from that you have decided without any understanding of what I am doing is perpetual motion?. I guess I was wrong choosing this forum to get my question answered because clearly you are NOT intelligent enough to grasp the concept and the basic laws of physics and electricity employed here I'll be going to another forum that has people with a brain in it! (That statement does not apply to you SGT. Wookie )This thread should be closed immediately. The OP is clearly confused over basic concepts, is pursuing a perpetual motion machine, and despite his assertions of attention to proper safety measures, is planning to build something hugely dangerous.
If he comes back with MUCH better documentation (pictures, block diagram, etc.), fine.
So I need an electromagnet with larger wire size wire on it? but that will consume more amperage from the battery. Also I have been re-thinking the voltage to the electromagnet I am thinking that given the size of the device that I may be able to go as low as 200-300 VDC to feed the electromagnet and still get a strong enough magnetic field to induce voltage in the generator coil. any thoughts on that?Hmm. That'll be ~1.108H inductance, it'll dissipate about 1.37kW of power due to the resistance of the conductor, RMS current will be around 1.7A. That's about twice the maximum allowed current of 860mA for chassis wiring.
Table of AWG sizes vs current limits: http://www.powerstream.com/Wire_Size.htm
Do you have a plan for getting rid of the 1.37kWatts of power that the coil will be dissipating? If not, you'll have a very quick melt down - that is, if your supply can keep up with it. That's a bit doubtful, as you'd need more input power to drive it.
Here are some power IGBT's that are rated for 1300V Vceo, cheapest Digikey had @ $4.41/ea:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=497-10990-5-ND
And you're calling ME the retard?...what is difference between switching polarity and spinning a magnet over a coil of wire to create electricity?
I am not sure if that is true I am hoping that I can keep the batteries charged enough to keep it going, yes if that is what your asking. If that breaks the code of conduct of here I am sorry I just wanted to know how to reverse polarity on a HV electromagnet automaticallyAs they say - "A picture is worth a thousand words". It would be useful to have a sketch of how this proposed system is configured. I'm certainly not confident of what is being proposed.
Is this system really an 'over unity' idea? Keeping in mind the TOS for this site.
So what you are saying is that the electromagnet will be acting as a generator coil itself and will producing a current in it once a load is connected to the generator? Won't the diode and capacitor used on the negative side of the electromagnet to collect the back emf also capture that induced voltage?And you're calling ME the retard?
Shaft work provided by an engine or some other energy-consuming device supplies the force to move a magnet through a field. Why is there a field? An offsetting magnetic field sets up in the generator coil once it begins supplying current. No load or current, no field, and the magnet is easy to spin. Once there's current flowing and a field developed, it takes work - energy - to move a magnet through that field. A portion of that shaft work is captured as electrical energy, as output from the generator. The laws of thermodynamics dictate that you cannot get more than unity recovery of the energy. So overall you consume coal, fuel oil, natural gas or whatever and get about half of the chemical energy back as electrical energy.
If you want to use electrical energy make the coils in the generator produce power, instead of spinning a magnet past them, ANY power extracted from the generator (essentially the secondary of a transformer) must first be supplied by the primary - your electromagnet.
Your electromagnet may draw little current when it's not loaded, but once it starts seeing an offsetting field in the secondary - a load - its current draw will increase in proportion. And you'll never get enough juice through it for the amount of power you want out the other end. But that doesn't matter, since the whole thing will consume more electricity than if you just connected your load directly to the source of power.
Let me get this straight...On the negative side going to the electromagnet I have place a diode and capacitor to collect back emf from the electromagnet then that is fed into a step-down transformer, from there it feeds an outlet that provides outdoor power and a battery charger is plugged into that outlet that charges the second battery (still need to build a circuit that reads each batteries voltage/amperage and switches between the two when the active battery reaches 25% discharge). I believe that will take care of any such melt down unless I am mistaken, I am not perfect and could have missed something though.
by Jake Hertz
by Duane Benson