cause my poor english, i make a draw here,i think original newman motor need improve desigh so that it become small but high effective and strong torque, but how can we do ?
just share your thought.
some times newman motor very seems like a bendini motor.
thks
btw ,my new desigh model for more test use will be done next week .what's newman motor bring to me .?
today i change vltage to dual 12V, adjust brush design, the rotation speed
and torque increase but power input
reduce more,so surprise!! what happan?
first test:
12v 10ma =120mw
this test:
24v 2ma =48mw
Quote from: ipower on August 14, 2008, 07:32:54 AM
today i change vltage to dual 12V, adjust brush design, the rotation speed
and torque increase but power input
reduce more,so surprise!! what happan?
first test:
12v 10ma =120mw
this test:
24v 2ma =48mw
Doubling the voltage increases the rate at which the current rises. Also, your coil has a property called inductance.
Voltage/Inductance = Change in Current / Change in time + Current * Resistance / Inductance.
Voltage/Inductance is constant for a constant voltage.
What happened most likely is that when you doubled the voltage, your motor spun more than twice as fast. This is because the current rises twice as fast, allowing the torque to rise twice as fast.
Apparently, the drag on your motor less than doubled when you had the motor running with higher voltage. That is why you probably ;) observed twice as many pulses per unit time when you had the 24 volt setting than when you had the 12 volt setting. But the current then has less than 50% as much time to rise, so the current will average less than it did previously.
If you put stronger magnets on there, as well as a significant mechanical load, you should be able to see the same effect, with more torque and rpm, without changing the input voltage. Some people gave up when they saw their motor slow down when they added more magnets. Most likely however, they didn't have a mechanical load on it. So the top RPM of their motor fell, although their torque could easily make up for the difference in terms of mechanical power output. My older (smaller) motors had more RPM but way less torque, and addition, more of its energy was wasted on vibration. Bigger here is better.
Torque is transfer of angular momentum/unit time. Therefore, the rise of current resulting in a linear rise in torque amounts to an acceleration in the transfer of angular momentum, and is to power in the same way that torque is to energy. Since torque is change of energy per change in angle, change in torque per change in time is the change of power per change in angle (as a result of divided by time).
If you take change in torque / change in time (= change in power per change in angle) and multiply by angular velocity (= change in angle / change in time), you get change in power divided by change in time. If you integrate that with respect to the duration of time, you should get a value for power in that time that is higher in your 24 volt case then your 12 volt case. And also, if you integrate that with respect to time a second time, you should get a value that suggests more mechanical energy is produced in that period of time whenever change of power / change in time is higher. That is, for a given time:
(Change of power / Change in time) is proportional to (Change of energy / Change in time), or total power.
The current you should be drawing from the batteries should increase only in proportion to the change in current per change in time and fall
inversely with how fast it is turning, provided that the rotary is efficient. The mechanical output power should rise proportionally to how fast energy stored in the coil is used to drive a mechanism (that is proportional to how fast the torque delivered to the rotor itself can rise***).
*** Torque in the magnetic field varies with its energy only by the tangent of the angle (this is because torque and energy only differ by a cross product and dot product respectively, as a product of coupled magnetic moments). As a result change of torque per change in time in electric motors is fundamentally the same as power, without regard to how fast the motor spins. Yet, the input energy is voltage times change of charge. The ratio of output to input therefore is (change in torque / (volt*change of charge*change of time)), and on a equal time basis, proportional to: (change in torque / utilization of electrostatic potential energy).
Fan motors in the market today are very efficient (joke ::)). The reason why they can't be improved as much is that they already have high current densities (current divided by area cross-section of conductor), so increasing voltage is very dangerous with them. With Newman motors, we begin with ultra low current densities, which is the reason why they don't get hot. If you apply enough voltage to them however, they should beat most motors out there. And also, as a result having fine turns of wire, the production of eddy current drag in the Newman motor is very minimal, which is why it is relatively efficient despite the lack of axial symmetry in the magnetic coupling.
@ ipower
If you use a bigger and heavier rotor with a strong magnetic flux, your motor will run slower with more torque but will need high voltage and less current to run. When using high voltage as Newman do in his motors in a big coil, you use the extremely high bemf effect of surface supraconductivity to create a stronger magnetic field than what you supply to increase torque by an exponential factor. That is the Newman motor's secret. E=MC2 (L)
Take care,
Michel
Quote from: Michelinho on August 30, 2008, 02:23:20 PM
you use the extremely high bemf effect of surface supraconductivity to create a stronger magnetic field than what you supply to increase torque by an exponential factor. That is the Newman motor's secret. E=MC2 (L)
bonjour Michel
are you sure of that ?
have you a self runner of the Newman motor's ?
@ tagor,
Yes, I am sure of that and the Newman will not be a self runner but will run with very little input.
The surface (skin) effect was studied by Tesla and others.
Take care,
Michel
Quote from: tagor on August 31, 2008, 03:47:10 AM
bonjour Michel
are you sure of that ?
have you a self runner of the Newman motor's ?
The common usage of the term back-emf shows over-simplified understanding of it.
For each circuit there is a given energy in the magnetic field that can be produced for a given current. As the current rises just after voltage is applied (i.e. when power changes), the magnetic field around the circuit quickly gets stronger. But any electrostatic potential energy in the circuit that is used in the system is simply waste.
Contrary to what many people assumed through unexplict teachings, the rate of change of energy in the magnetic field is a function of applied voltage minus current*resistance.Therefore, as current rises, not all voltage is used to produce the magnetic flux by increasing the current for the given inductance, but now some of it is used to sustain the current that heats the coil due to the resistance. That power behind that is simply the result of the depletion of electrical potential energy of like-charges (electrons) that tend to repel themselves along the circuit.
That is to say, the decline in the growth rate in the magnetic field is actually due to the presence of energy drained which does not contribute at all to the magnetic field (which largely, if not completely, is dissapated as heat due to the resistance of the conducting path).Thus, a given voltage really does produce magnetic flux, not a given current (where to produce strictly means to increase with time) . After all, the definition of voltage is the change of magnetic flux per change in time!The magnetic flux is the magnetic field times area. Thus, to get the magnetic field
B, you take voltage contributed to the magnetism of the coil integrated with respect to time and then divide by an area through which all of that magnetic flux flows through within the coil. When a changing magnetic field couples with a unchanging magnetic field such as that from permanent magnets, the energy of the magnetic field increases at a rate at first proportional the applied voltage, until the current approaches the maximum, where the energy of the magnetic field stagnated and is no longer further contributed in net by energy used by the circuit, until the applied voltage is reduced so that the cycle begin again.
Thus, current and voltage must be constantly rising and falling within the circuit to produce the changes in the magnetic field required to do work. If power is constant, then the magnetic field of the coil can do no work, just as permanent magnets can do no work.Thus, as shown in my previous post in this thread, both the power and energy you can derive from a given Newman machine is proportional to the change of power per change in time.
this is my new big motor with 6x6CM magnet ,tested with 400V input voltage,very fast rotation,i have no mesure meter so i dont know speed, the current is about 3MA,and power input is 400X3=1.2W, so surprise, newman motor should very high effective,but i think its not a ou device. it just useful to lower torque low input aera , when make load ,the current increase very fast.
just for u this reffence.
Ipower,
can you please post a youtube video of your motor ?
How many Kg of wire do you have on your coil, what is its DC ohmical resistance and
what current is the motor drawing, when you brake down the
rotor with your fingers ?
Many thanks.
Quote from: hartiberlin on September 11, 2008, 04:03:11 PM
Ipower,
can you please post a youtube video of your motor ?
How many Kg of wire do you have on your coil, what is its DC ohmical resistance and
what current is the motor drawing, when you brake down the
rotor with your fingers ?
Many thanks.
i make double coils ,one to power in and another load a 10W/220v lamp,when turn on lamp ,it light but input brush have large spit and speed down low then stop, the coil is about 600ohm, 400uf/600v capatitor can drive it 30s while turn off power input.
Hi Ipower,
try to use an Avramenko plug ( 2 x 1N4148 diodes and a cap)
on the second coil( output coil), so to not have a closed current coil.
Then you can try to power your lamps via the Avramenko plug.
This will not brake the speed of the rotor...
Please let us know, what this change will get you.
Many thanks.