Not much luck making the resistive disk, but I came up with a simple circuit to make the single polarity waves with resistance / impedance. I suppose it's more of impedance but it restricts current flow like resistance.
I built a test circuit and the results were encouraging.. The advantage of this method is that it uses no resistors to burn away heat. The impedance causing component allows me to harvest most the energy back instead of burning it..
I was able to verify the xformer output resembles a 2 polarity sinewave as expected and measurable current indeed dumps back to the battery.
Now obviously on a system like this we want to increase frequency, but it is not as easy as just faster switching. The frequency is dependent on the capacity of the cap, because it has to fill and empty each cycle. So the switching delays need to be dialed into the capacitor value used..
My first build was all soldered and I was switching hot-side like the diagram shows. Because it was soldered in, I can not easily swap caps to increase frequency, and I was using a 1,000uf cap, so the frequency was very slow. Even so, the output to input efficiency was not bad at all. When dialed in, I saw upward of 70% efficiency.
I am going to re-build with N channel mosfets with terminals so I can swap the cap around easily to increase switching speed.
One may ask, what's the point in all this.. It is my hope the impedance will mimic the rotor pulling away, thus limiting the CEMF back to the primary when the input wave is declining from peak to zero. And using the capacitor allows me to collect that energy back.
I will try to show some videos once I get it re-built
I built a test circuit and the results were encouraging.. The advantage of this method is that it uses no resistors to burn away heat. The impedance causing component allows me to harvest most the energy back instead of burning it..
- Mosfet 1 closes while Mosfet 2 is open. Current flows to the capacitor until the current stops. The cap Negative lead feeds the transformers primary. Then out of the transformer back to the battery.
- The cap in series causes a growing then declining wave, And can be shaped with the timing of the mosfet and cap value. So this single polarity wave is caused by added impedance, which should be equivalent to distance.
- When the Cap is filled, Mosfet 1 Opens at the same time Mosfet 2 Closes. The Capacitor is then connected to a Boost Converter which drains the capacitors stored power back to the battery.
- Finally the primary circuit gets a diode from the Hot lead of the cap to the negative lead of the primary inductor, so the counter EMF of the transformer can return to the coil even though the powering circuit is broken.
I was able to verify the xformer output resembles a 2 polarity sinewave as expected and measurable current indeed dumps back to the battery.
Now obviously on a system like this we want to increase frequency, but it is not as easy as just faster switching. The frequency is dependent on the capacity of the cap, because it has to fill and empty each cycle. So the switching delays need to be dialed into the capacitor value used..
My first build was all soldered and I was switching hot-side like the diagram shows. Because it was soldered in, I can not easily swap caps to increase frequency, and I was using a 1,000uf cap, so the frequency was very slow. Even so, the output to input efficiency was not bad at all. When dialed in, I saw upward of 70% efficiency.
I am going to re-build with N channel mosfets with terminals so I can swap the cap around easily to increase switching speed.
One may ask, what's the point in all this.. It is my hope the impedance will mimic the rotor pulling away, thus limiting the CEMF back to the primary when the input wave is declining from peak to zero. And using the capacitor allows me to collect that energy back.
I will try to show some videos once I get it re-built
