|
Hi Chet,
as you probably know, most batteries have internal resistance that make them inefficient under high current drain.
For example, a 1 ohm internal resisitance and 1 amp draw, will drop the battery terminal voltage by 1 Volt. This wastes 1 watt and delivers 8 watts to the load. (assuming a 9 V battery)
As an exageration, drawing 9 amps will obviously drop the voltage to 0, and this occurs if you short the battery, and then all power will be dissipated inside the battery, in it's internal resistance. By the way, this internal resistance is a function of amperage and other factors.
Now, the question that beggs an answer is: how can we extract the most energy from a battery?
The answer obviously is to drain it very very slowly. Assume I drain the battery mentioned above at 1 mA. The power dissipated internaly is I^2 * R = 0.001^2 * 1 = 1e-6 watts, or 1 micro-watt. The battery will be putting out approximatley 9 mW to the load, and efficiency would be (9e-3 - 1e-6) / (9e-3) = 99.99%
If we have those kinds of efficiencies then we can utilize most of the energy in a battery, and there is a whole lot in there, but obviously we have some issues to deal with, like draining very little current from a battery can take a VERY LONG TIME to "get at" all that energy stored in there.
So we have a TIME vs. EFFICIENCY constraint !
So, I believe Ismael is slowly charging up a capacitor to very high voltage (7500 V) and then discharging into the coils. This is a very basic experiment done in most physics classes, and if he is smart I'm sure he recycles some of the unused kickback energy as well.
Now, the power quoted as 1200 Hp is not something to be amazed at, because of the discharge duration. Here's some more amazing numbers for you.
Charge a 20 uF capacitor to 1000 volts => energy content = 0.5*C*V^2 = (10e-6) * (1000)^2 = 10 Joules
Now, discharge the capacitor into a short circuit, with minimum inductance, so that the caps discharge in let's say 100 nS, then the power flow would be approximated as: Jouls/sec = 10/1e-7 = 100 Mega Watt = 133,333 Horse power.
So you see, it's realy the duration of the discharge and how quickly you can discharge the capacitors.
Now, on a different note. The technology discussed by Ismael, i.e. shorting and unshorting the generator coils at the peak of the induced voltage is very interesting. From a circuit point of view it's not that amazing, but from a magnetic point of view it could be the key to some power extraction via resonance from the magnets or the magnetic field itself. That's why I say that I'm not down playing the concepts, just doing some math.
Now here's my idea for an electric vehicle. Use the best batteries you can get for the price alloted for the project. Then use a magnetic flywheel as the high power buffer, and slowly ramp up the flywheel so you have lots of power available for acceleration, then you will feel like you are driving a sports car with only perhaps one battery on board. Because now you can accelerate like mad, and also break hard, and when you do, you will dump a lot of power back in the flywheel and it can take it, but the batteries can not, or rather have limits and your energy will be wasted. So the limitations for the electric vehicles, as far as performance, is realy the amount of POWER that they can handle, NOT ENERGY necessarily. Energy capacity playes a part in HOW FAR, you can travel, and of course that is something to consider.
Hope that sheds some light on what I was talking about. Please keep us posted on anything new.
EM
|
Author
Topic: The Death of the Lenz Law (Read 164731 times)
