High Efficiency Mosfet Switching for Pulse Motor

[Energy Hack]

Hi All,

I've been working on various Pulse Motors using a simple Mosfet switching circuit to turn coils ON/OFF.  Inductive spike is recovered to second battery bank that sits in parallel to drive bank and the banks are swapped every minute or so.  I can measure about 75-80% power recovery to the second bank.  Looking for tips to improve the switching circuit as I believe that is where the magic happens.  If I can get to 100% recovery then next step is to mechanically recover a little power from the rotor.

See attached diagram of set up and best results to date.  Thanks!

[bistander]

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[aussiebattler]

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I agree

[Cadman]

Energy Hack,

As long as you are discarding the initial coil energizing current your existing setup will likely be under unity over all.

Since you are using pulsed DC there are at least two methods that may improve the situation.

1 is to run your motor between battery positives in order to recover a portion of that energizing current. Not easy, but doable.

2 is to add secondary generating windings around, or inside of, your motor coils with a diode that allows those those coils to conduct only during the collapse of the primary pulse. Doing it this way keeps the secondary from interfering with the primary motor coil pulse. But, since you're using air core you may be able to omit the diode and use a rectifier with the secondary for even more output. To make use of the secondary generation, the emf from these coils has to be greater than the charge batteries so it might be advantageous to store this in caps and use a timed cap discharge.

[kolbacict]

I did this a long time ago using a normal two-phase computer fan.
Only the circuit was completely changed, there was only one transistor.
Like a blocking generator. The miracle did not happen, both batteries gradually discharged.