03-05-2017, 09:57 PM
my 2 cents here.... I don't think a BIG neo is needed, we only need the fields to penetrate both sides of the coil, as long as it does this we can get the RPM we want without some of the forces Yaro is talking about. think about the colored cloverleaf Dave Wing posted. you can build that with 4 neo magnets and iron connecting then thru the center. I would not think that anything larger than a 1/2 by 1/2 by 2 inch long neo would be all we need. if you 3D printed in nylon or a carbon your strength would be there, and you could design the iron pole pieces to slide in to connect the fields before you slid in the magnets. you can make the magnets completely captive. perhaps a wider instead of thicker magnet is the answer.
of course there are parameters we need to run in so there will be a best size ratio for the magnets... I also think perhaps speed can be achieved by having the timing advance as RPM changes. I don't know this for sure it is just a guess based on the SG work I have done
Last edited by Tom C; 03-05-2017 at 10:02 PM.
experimental Kits, chargers and solar trackers
03-22-2017, 12:21 PM
Hello to @all,
Progress on the ZFM Proto has continued from the last video 7B. The timing configuration was modified to a friendlier arrangement using a balanced 60 degree firing arc duration with the Aluminum rotor. This arrangement was then tested and data gathered for baseline comparison purposes and then the new Iron rotor was installed in the motor.
For this post I will not include all the data, but will state that the overall performance between the Aluminum and Iron rotors is not really very different. Both rotors produce approximately the same RPM and amperage draw. Perhaps the iron rotor may have a bit more torque, but that is anecdotal based on the two finger shaft test.
There was the intention of doing a video on the impact of timing on the operation of the ZFM along with its impact on RPM and amperage draw - but that will wait until it is needed for demonstration. For these above tests the combination of firing angle and advance have been kept within the constraints suggested by Peter Lindemman way earlier in this thread and that is less than a total of 90 degrees or so for the duration plus advance. All well within the degree arc coverage of a coil segment.
There are a number of take-aways here:
1) The duration of the firing arc will increase or decrease the amperage draw from the primary battery.
2) The advance has a major impact on the amperage draw and final RPM.
3) For nearly every configuration of Timing the ZFM will continue to build speed from the initial RPM value by ~5% or more for several minutes or more.
4) The greatest torque and RPM are achieved by progressively increasing the operating voltage - ie. 12v, 24v, and 36v.
5) The motor coils will normally warm up a bit over room temperature - usually by a maximum of ~5F.
6) The Bipolar switch will certainly heat up quite a bit, but that is dependent on the firing arc duration and advance.
Additional experimentation has demonstrated that the time required to energize and de-energize the existing coils is a critical factor in the ZFM's high speed operational modes and that the harmonics produced by the firing rate influence the value of the RPM and amperage draw.
Another interesting observation is that this experimentation also appears to suggest the formation of the clover leaf pattern of the magnetic fields surrounding the coils as depicted in JB's Lab sketch, however further work on this has been put aside until later this summer. The current effort is to attach a small pump to the ZFM and physically pump water while collecting the relevant performance data - where the rubber meets the road.
The above post may seem overly generalized, but it does contain many interesting nuggets for further thought and exploration.
Last edited by Yaro1776; 03-22-2017 at 06:37 PM.
Reason: Clarify firing arc suggestion