Is this the first selfrunning overunity motor w/o batteries ? Mike?s motor

[z_p_e]

Great stuff going on here guys!

Here is my new ferrite magnet window motor...

Dave.

As usual, nice work Dave!

What are your coil specs?

[CTG Labs]

Hi Darren,

At the moment I have used 0.28mm wire for the trigger and drive, about 30ohms and 0.45mm wire for the gen coil.

The motor runs REAL fast once you start adjust the resistance to the base of Q1.  The speed increases really fast, and the input current drops a lot to.  But at the moment the input current starts around 200mA and once its up to speed is down to about 160mA or less.  So I am going to add more turns to increase the resistance some more and bring the operating current down further.

My other motor runs on 3ma with Hall IC switching and good speed, so it is possible to get these running on basically nothing as John has always said.

What is interesting to me is that we can increase the speed and lower the power used at the same time.  But as the speed increases the spike voltages increase too.  For instance, at the lower speed the spikes are 50v, at max speed they are 180v.

More details later.


Dave.

[z_p_e]

I am thinking of using a coil-coil k of between 0.5 and 0.7, and a magnet-coil k of about 0.3

Since you know you have the coils about right now, how about getting the magnet k by adjusting at the appropriate frequency for voltages that approximately match Mike's?

I guess for the coil to coil you will have to go with .5-.7 if that is what is typical for coil to coil.

db

Guys,

It looks like my hunch turned out to be correct. Just playing a little with separate coupling factors, it's become apparent that this is the cause of the double-spike spacing, and the more pronounced and curvy DC-shift seen on the D2 shot when Q2/3 turn ON.

So, I'm re-doing the model using corrected inductances for the coils as per Peter's measurements he kindly posted, and with the pm-coil and coil-coil coupling at different values.

I will post new waveforms when I am happy with the results and I feel I am there. Once I am "there", the last frontier will be to search for that ever-elusive partial-cycle I highlighted in Mike's D2 shot with the hall switching in.

Can't be certain that this is the ou mechanism of the motor, but at least it gives us something to shoot for. If we can reproduce this waveform, we should have a better insight into what's going on in the motor.

Darren

[CTG Labs]

Also, my work can be found here:  http://www.ctglabs.com/window.htm

Test results, etc, will be posted when there are some...


Dave.

[z_p_e]

Dave,

Your observation of decreasing supply current with increasing speed is typical of most if not all pulse-type motors, isn't it?

As speed increases, the ON-time of the transistors decreases accordingly.

Increasing the base resistance of Q1 offers less (or equal) load to the motor and as a result it will spin faster. Less Lenz = more speed. Because induced voltage also increases with increasing speed, you may actually just be compensating for this by increasing the base resistance.... i.e. Ib remains constant.

I have an idea for a small circuit mod that will do this automatically for you, and hence keep the "Rb" value at optimum at all times.

Darren