Thinking about building a pulse motor.

with 2 separate pulsed coils, which back emfs charges separate caps that are discharged into the other coil.

so the idea is building a pulse motor that re uses the back emf.

driven by fast mosfets, that are triggered by LED/ photo sensors, so no hall sensor needed.

coils will be air coils, so this would be a very fast motor.

I still have the same Idea, but advanced it a bit more.

Based on opposing magnetic fields creating movement (separation).

coils ar bifilar, and are pulsed out of phase with 50% duty cycle.
When one coil turns off, it has no opposing magnet, creates inductive spike, that is fed in to the next coil that does have a opposing magnet.
Magnetic field energy (negative inductive spike) of one bifilar coil is pumped into dielectric field of other bifilar coil, that transforms it into its own magnetic field.
therefor re-using the electric energy, reducing input power, making it very efficient.

no storage caps are needed, since the dielectric field of the bifilar coil acts as a capacitor for the voltage of the inductive spike.



Question: If I dont use a hall sensor, or other method of triggering, would this still work when I pulse at a fixed frequency, and give the wheel a push? Or does it need a sensor to work properly?

Rick Friedrich in YT has half of this back EMF motor. He just has one motor and he uses the spike to charge a battery.

Maybe you could use his diagrams as a base?

Quote from Belfior on August 27th, 2019, 12:04 PM

Rick Friedrich in YT has half of this back EMF motor. He just has one motor and he uses the spike to charge a battery.

Maybe you could use his diagrams as a base?

Thanks,  do you have a direct link to his schematic?

I could do a quick test of the circuit without any moters, to see if there is a reduction in current.

just 2 coils, no magnets
2 mosfets, driving the coils out of phase.

If the magnet approaches the coil, the coil isn't emergised.

it is not open ended, but tied to - V (via the other coil, which is energised so the diode is open.

edit: there is another diode that might cause a problem opening  the loop. but voltage induced would be? good?


the approachimg magnet cant induce a voltage in the coil as it is close looped.

So... no voltage no current no magmetic field. Perfect.

Then when magnet is dead center the coil, or slightly passed (or the magnetic has enough inertia) the coil is switched to V+(acts as ground) and is energised.

coil opposes magnet and repulsion catapulses it away, giving power to the motor.

At the same time the mosfet closes the switch on the coil with the magnet above it,
the other mosfet (coil without magnet) opens the switch, and the produced inductive spike (magnetic field energy) is fed into the other coil (kicking  the magnet away).

The magnet moving away from coil does induce a counter voltage, that is opposing (counter emf). but its force fades as the the magnet moves away.

I drew it as a negative impulse motor.
but it should just as well work with positive voltages, which makes switching easier, as it is done with a regular uncomplicated low side switch.

I found a 16 coil 8 magnet motor, which design I really like

https://s.click.aliexpress.com/e/D35LtmAk

It has Hall sensors, and is easy adjustable.

Since the switch off speed in my design is very important, to create maximum inductive spike energy, I will need to come up with a Hall sensor gate driver which is fast switching, and simultaneous...

edit: I used  a flipflop before, It could be triggered by a hall