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I've come up with another thought about matching the time constant.
As we know the L/R of the coil is to be matched with the speed of the magnet passing by. So actually there are 2 time variables: coil time constant and magnet passing time. We have observed that if magnet passing time (hence inverse RPM) is less than coil time constant, Lenz can be neutralized. There are two ways we can go about by doing this: One is to increase L/R and the other is RPM. Coil L/R is limited because of design, for example, a typical 10mH 2 Ohm is certain size for the rotor and we can't improve it much without increasing its size.
What I'd like to emphasize on is the magnet passing time. This time variable only applies when the coil is loaded and the time count begins when current start to increase. We have the ability to control this parameter by loading the coil only at certain point for a certain duration.
I've drawn up 3 different time variables scenarios for a certain RPM. The biggest time cover the whole waveform equivalent to continuous shorting. The two smaller time is base on when we choose to load the coil and for how long, so for certain RPM we can match any L/R time constant. In theory, we can neutralized Lenz even with speed of a few RPM by shorting it at top dead center.
The picture is kind of small on my computer. Could you explain it?
It's all the coils mounted around the fixed plate on both sides of the plates, one side for the motor, other side for the generator.
the rotor has an outer set of magnets for the motor on the longer arm so to speak, and an inner circle of magnets on the shorter arm so to speak. If you mix the coils uses on each side of the mount you can change the timing by shifting the inner part of the rotor radially causing a shift in phase? This also gives a difference in RPM's/ speed ratio between different coils if set up to do .so
Last edited by Rubberband; 09-21-2011, 01:23 AM.
Reason: for all points missed making earlier
It's all the coils mounted around the fixed plate on both sides of the plates, one side for the motor, other side for the generator.
the rotor has an outer set of magnets for the motor on the longer arm so to speak, and an inner circle of magnets on the shorter arm so to speak. If you mix the coils uses on each side of the mount you can change the timing by shifting the inner part of the rotor radially causing a shift in phase? This also gives a difference in RPM's/ speed ratio between different coils if set up to do .so
Interesting idea. I'm not sure I grasp your idea completely so if I don't please continue to elaborate. Mechanics are hard to convey in text and 2d image format.
Essentially are you suggesting spinning the magnets in one direction and the coils in the opposite direction? That's a great idea!! It is more mechanical in nature, and will be difficult for testing stages, but once this generator is fully understood you could design a generator requiring half the RPM by spinning the magnets and coils in opposite directions! It would need brushes, etc, but with a good design I think it would help us achieve lenz tricking with half the RPM (danger). Nice!
Another thing this would do is allow you to mechanically time the firing and load time of each coil. You could do this by designing your mechanical brush switches carefully. I think there is potential with this idea in the future!
As far as phase shifting, the phase shift we are looking for is only within the generator coil itself. Essentially we are trying to control the time from when the magnet creates a changing field around the coil to the time that the coil receives the magnetic field and generates an electrical current to the time that the new electrical current creates a counter magnetic field in reverse of the one the magnet is creating. Changing coil location wont help this, but it can help us reduce the magnet bypass time!
Trust your own instinct. Your mistakes might as well be your own, instead of someone else's ~BW~ It's kind of fun to do the impossible ~WD~ From now on, I'll connect the dots my own way ~BW~ If I shall be like him, who shall be like me? ~LR~ Had I not created my whole world, I would certainly have died in other people’s ~AN~
I've come up with another thought about matching the time constant.
As we know the L/R of the coil is to be matched with the speed of the magnet passing by. So actually there are 2 time variables: coil time constant and magnet passing time. We have observed that if magnet passing time (hence inverse RPM) is less than coil time constant, Lenz can be neutralized. There are two ways we can go about by doing this: One is to increase L/R and the other is RPM. Coil L/R is limited because of design, for example, a typical 10mH 2 Ohm is certain size for the rotor and we can't improve it much without increasing its size.
What I'd like to emphasize on is the magnet passing time. This time variable only applies when the coil is loaded and the time count begins when current start to increase. We have the ability to control this parameter by loading the coil only at certain point for a certain duration.
I've drawn up 3 different time variables scenarios for a certain RPM. The biggest time cover the whole waveform equivalent to continuous shorting. The two smaller time is base on when we choose to load the coil and for how long, so for certain RPM we can match any L/R time constant. In theory, we can neutralized Lenz even with speed of a few RPM by shorting it at top dead center.
This would allow us a better control over lenz tricking, although it would be at the expense of energy creation. Still though, it may give us better control especially as we test these generators. My mind will have to think on this a little more.
Trust your own instinct. Your mistakes might as well be your own, instead of someone else's ~BW~ It's kind of fun to do the impossible ~WD~ From now on, I'll connect the dots my own way ~BW~ If I shall be like him, who shall be like me? ~LR~ Had I not created my whole world, I would certainly have died in other people’s ~AN~
Has anyone every tried just winding a thicker wire coil over an active generator coil and shorting it or using it in other ways. Maye this would steer the drag away from the core and gen coils.
The same "over coil" could be used on a drive coil and connected to the drive coil via a diode to capture and use the flyback. Maybe the drive coil with over coil could provide a 1-2 punch.
But don't try this before you do some basic coil wind direction and polarity tests since your coils are all so ingeniously glued to their plate, you cannot make a mistake in coil wind side and direction.
I'd say 5-6 turns of #10. That would be easy to unwind and re-wind the other way should your polarities require it.
My test motor speeds up under load , I used a microwave fan coil for the generator, paralleled with an ac cap, then to a FW rectifier made of 3 Schottky barrier diodes (from computer PSU`s SBL3040). Thanks Toranarod for the schottky diode info.
The speedup effect is (for me) is more dramatic with a 3uF ac cap paralleled to the coil.
input power 5v 27mA, loads the motor considerably with the coil in place and the rpm is 670 with no load, with a 4w load it increases to 1420rpm. Output is 6.1v 2.6mA
Better output power however is with a 0.94uF cap using 8v 32mA,
no load rpm 2844, 4w load = 2976rpm. Output voltage is 6.8v 6mA.
I havent put the scope on the gen coil yet but will tonight. The rpm is measured with a reed switch to parallel port so i might miss a few pulses here and there but the speedup is an audibly significant indication , PSU is a HP 6632A lab supply and output measured with HP 34401A for amps and a fluke75 for volts, so again approximation with digital meters.
The rotor is 120mm diameter fixed with 8 13x6mm rectangular magnets, dual reeds in series supply a 400t sewing bobbin coil (single strand) with a pulse, the core is a 6x30mm ferrite. simple stuff .
Cheers
Jim
I have some powdered graphite (flakes) on hand. It is interesting. It appears slightly magnetic (or slightly anti-magnetic). I sprinkled some on a piece of paper and put a .5" neo underneath. It stood the flakes on end but didn't move them at all.
Trust your own instinct. Your mistakes might as well be your own, instead of someone else's ~BW~ It's kind of fun to do the impossible ~WD~ From now on, I'll connect the dots my own way ~BW~ If I shall be like him, who shall be like me? ~LR~ Had I not created my whole world, I would certainly have died in other people’s ~AN~
Today a hurried and ran a chart comparing magnet width to height ratios. I recorded the gauss calculation at 1/4" above the magnet face for every instance. In this study I was trying to determine the best width to height ratio so we can save both money, and rotor space.
Example: Say you need to reach a certain gauss for your coil. You could use either a wide and flat magnet or a skinny and tall magnet. Which one would be better? Well if we are trying to minimize the magnet bypass time obviously the skinny magnet is what you would want. But then how tall does it have to be? That is what this information will help you decide.
For the data I picked a constant magnet width (.5 inches for one line and 1.0 inches for the second line). I then decided to start with a magnet height of 1/4th the width. I recorded the gauss for this magnet at 1/4th inch above the magnet face. I then added another fourth to the height and recorded the gauss. And again, another 1/4th of the width added to the height and recorded.
Thus the measurements go like this...
Width x Height
.5 x .125
.5 x .25
.5 x .375
etc.
I plotted the results on the chart below. The X axis represents the height of the magnet as a ratio of the magnet width. You will notice that both the .5" and the 1" magnets had a similar line. According to both of the data lines your best use of money and rotor space is achieved when your magnet height is 2 times larger than the magnet width. This should help you save money and maximize the change in flux in a given rotor size.
I did this to help me decide the most effective magnets to buy but I thought you may want to know it as well.
Trust your own instinct. Your mistakes might as well be your own, instead of someone else's ~BW~ It's kind of fun to do the impossible ~WD~ From now on, I'll connect the dots my own way ~BW~ If I shall be like him, who shall be like me? ~LR~ Had I not created my whole world, I would certainly have died in other people’s ~AN~
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