@Plengo

That is a great video. Thanks.

Is it possible for you to record how you connected the drive coils. Is the pulse entering the first drive coil on the side that is closest to the core or not. Have you tested it both ways?

Also, I am very curious about one major test if possible. If you add another coil in series with the two already mounted drive coils. Maybe the primary of a regular transformer coil of good mH value. It should not be mounted. Just keep it on the table and connect it in series with the drive coils, but not on the side that receives the pulse.

My theory is that this will create a shift in the center point of the two drive coils more to the end of the second coil making both coils more reactive, hence providing more output field to the rotor magnets.

Very good work indeed.

wattsup

Hello Bolt & Everyone,

Thank you very much for the positive response. Bolt, I was particularly interested in this comment you made below:

QuoteThere are several methods to keep the PF in the desired phase including switching on and off the load in synchronous mode, coil shorting, passive tuned, Sine clipping using zener triggers, bucket brigade delay lines and using several PF tuned stages to cascade the COP or in other words provide greater and greater source to load isolation.

I believe I am familiar with all of the methods other than the bucket brigade delay lines and the cascaded, tuned, stages. Would you mind posting an example or explanation of how such a circuit is arranged? I plan to do some testing myself soon and would like to try several different topologies to compare the performance, though my favorite method at this point is coil shorting. Which method out of the ones you listed do you think is the best to work with (performance wise)?

@keykhin & Plengo,

Nice replications you have there! But as others have stated, I don't think you will see the full benefit of the AC capacitor until you tune the value to match the equivalent frequency of the induced EMF in your generator coils. Though it is encouraging to see that the HF ringing created by the capacitor can reduce the load on your motor, the tuning is absolutely critical to really get the benefit. The simple way to determine the capacitance you need is to simply rework the standard LC resonant frequency formula to solve for C based on the desired RPM of your motor:

C = 900 / [L * (Pi * Poles * RPM)^2]

where:

C = Capacitance of the capacitor (In Farads)
L = Inductance of the generator coil (in Henries) (or coils if multiple coils are wired together)
Pi = Pi (Ï€)
Poles = Number of magnets on your motor's rotor
RPM = RPMs that you will be tuning the coil to run at.

This formula is extremely useful for quickly determining the value of the tuning cap for your pulse motor. And since everyone here has different coils, motors and rotational speeds, you can all determine which cap value will work best for you based on your design's operating parameters.

For Example, for my pulse motor, my rotor has four magnets with two sets of coils on either side of the rotor. If I want to use one pair of coils as drivers and the other pair as the generator, I can do that.

In my case, the inductance of each of my coils is 1.1mH. So if I have the generator cois wired in series, that gives me 2.2 mH for the L value in the formula.

If I want to run my motor at, say, 6000 RPMs and tune for that speed, I can plug these values into the formula to calculate the capacitance, C, like so:

C = 900 / [0.0022 * (3.14159 * 4 * 6000)^2] = 71.97E-6 = 71.97 uF.

Remember, the whole point is to tune the motor to run at resonance, which creates the 90-degree phase shift between the voltage and current waveforms. In this state, the Power Factor is 0 (system is totally reactive), the VSWR is infinity, and you have no loading on the generator itself :-).

- Jason O

Quote from: Jdo300 on June 13, 2011, 10:34:50 AM
Hello Bolt & Everyone,

Thank you very much for the positive response. Bolt, I was particularly interested in this comment you made below:

I believe I am familiar with all of the methods other than the bucket brigade delay lines and the cascaded, tuned, stages. Would you mind posting an example or explanation of how such a circuit is arranged? I plan to do some testing myself soon and would like to try several different topologies to compare the performance, though my favorite method at this point is coil shorting. Which method out of the ones you listed do you think is the best to work with (performance wise)?

@keykhin & Plengo,

Nice replications you have there! But as others have stated, I don't think you will see the full benefit of the AC capacitor until you tune the value to match the equivalent frequency of the induced EMF in your generator coils. Though it is encouraging to see that the HF ringing created by the capacitor can reduce the load on your motor, the tuning is absolutely critical to really get the benefit. The simple way to determine the capacitance you need is to simply rework the standard LC resonant frequency formula to solve for C based on the desired RPM of your motor:

C = 900 / [L * (Pi * Poles * RPM)^2]

where:

C = Capacitance of the capacitor (In Farads)
L = Inductance of the generator coil (in Henries) (or coils if multiple coils are wired together)
Pi = Pi (Ï€)
Poles = Number of magnets on your motor's rotor
RPM = RPMs that you will be tuning the coil to run at.

This formula is extremely useful for quickly determining the value of the tuning cap for your pulse motor. And since everyone here has different coils, motors and rotational speeds, you can all determine which cap value will work best for you based on your design's operating parameters.

For Example, for my pulse motor, my rotor has four magnets with two sets of coils on either side of the rotor. If I want to use one pair of coils as drivers and the other pair as the generator, I can do that.

In my case, the inductance of each of my coils is 1.1mH. So if I have the generator cois wired in series, that gives me 2.2 mH for the L value in the formula.

If I want to run my motor at, say, 6000 RPMs and tune for that speed, I can plug these values into the formula to calculate the capacitance, C, like so:

C = 900 / [0.0022 * (3.14159 * 4 * 6000)^2] = 71.97E-6 = 71.97 uF.

Remember, the whole point is to tune the motor to run at resonance, which creates the 90-degree phase shift between the voltage and current waveforms. In this state, the Power Factor is 0 (system is totally reactive), the VSWR is infinity, and you have no loading on the generator itself :-).

- Jason O

Correct in my prior posts i stated the tuning cap is probably going to be around 10uf to 100uf which need tuning within 0.1uf then fine tuned by moving the back end magnet to tweak the inductance.

Bucket brigade is a lot of 10,000uf load caps which are switched sequentially using an array of fets. So the first cap sees the joules from the generator then it charges the first dump cap. The cap is then disconnected from the generator then it switches to a second cap to fill that. Then that cap disconnects and fills a third cap then that disconnects then finally is connected to the load. Even more so the cap bank is in an ARRAY so that the caps are 3 layers deep by say 9 layers wide.  As the first layer has just discharged into the load the second layer is charging the 2rd cap while the 3rd layer is just taking a fresh generator sample. It bit complex but hopefully you can see that caps move energy through time.

What this does is move JOULES thru time to convert VARS to WATTS without any loading whatsoever.  This system is currently employed on a 2000 watt OU RV system.

Passive tuned is just RLC tuning which is RPM and LOAD specific. If you change the desired load or rpm outside of the system bandwidth the system requires complete retuning.

Cascaded systems are where the generator coil is tuned to yet another coil sub system that runs at entirely different frequency. Usually the prime frequency is very high in the hundreds of Khz this creates inference to the 2nd RLC but its NOT parametric perhaps running hundreds of Hz.  This then goes to a 3rd stage at even lower frequency say 60 Hz. Each layer provides greater source to load isolation so the the COP's are cascaded. eg stage 1 COP 4.5, stage 2 COP 6.5, stage 3 COP 4.3, each stage is multiplied  together =  COP = 125.775
Kapanadze Example a 50w driver *    COP 125.775     = 6288.75 watts  which is about 10% of the VARS so this system actually pumping around 62.88 KVARS!!

@Jdo300: Your information is priceless, thanks a lot.

Excuse me asking , but what is VARS .