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Old 05-04-2019, 06:51 PM
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sampojo sampojo is offline
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Join Date: Nov 2010
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followup on BLDC project

Quote:
Originally Posted by Ufopolitics View Post
Hello to All,

Well, finally the second part video is here...

ASYMMETRIC BRUSHLESS PART 2 - YouTube

I did the board wiring with just small color coded insulated wires, for easier replacement of the small caps as well as taking on-off the whole laminated core...swapping rotation direction, etc.

[IMG][/IMG]

I had problems with one of the sensors...one of its outputs (blue)started to show a small resistance value (20 ohms) with positive Vcc, not good, that pair was pulsing too weak, had to replace IC...



I also had problems with small original caps retaining some Milli Voltage steadily, and not discharging to zero or close to like supposed to...due to higher radiant, higher BEMF Spikes because of more copper on same steel volume...I will eventually measure this exact running values when I connect all four outputs to Scope...The Solution was higher Voltage rated caps, same value, or 2.2 uF but 100V...then retention of voltage went to 0.04 to 0.02...or nothing...we have more voltage in our fingers...

In future tests...I am looking at adding some small Non Polarized Caps Parallel to each Pair, about same timing capacitance or 2.2 uF...creating "Momentary" LC Tank circuits for each...in order to "flash" store Radiant in each Off Time Pulse, reversing magnetic polarity...and use it more robust to assist motor Pairs while being turned On by Hot Pulses...same deal we had before on our Brush Type Asymmetric Machines, except that here we have plenty of space to do it externally and stationary...

The Basic Results were:

Two Symmetric Fans in Parallel running at :

11.5 Volts drew 0.47 Amps, each outputting around 2000 RPM's

One Asymmetric Fan, connecting All Pairs:

11.5 Volts drew 0.39 Amps, outputting around 2700 RPM's

At 13.8 Volts drew 0.46 Amps reaching around 3000 RPM's

The idea of building this type of small Four Poles ...is to be able to "modulate" sections like this structure and spread them along bigger circumference machines...in series, to add resistance values, decreasing amp draw...every 90, 120...etc,etc.

I am currently working on a bigger 24 Teeth Laminated Core for future Asymmetric BLDC model...maybe a Six Phase Circuit...a P24, 48 Coil Spiral...

[IMG][/IMG]

Comparing Diameters... :

[IMG][/IMG]



Regards to All



Ufopolitics

Looking at this from page 198, kind of a loose end. Still looking at the BLDC fan motor demo you did to understand how to introduce the extra hall sensor. Also wondering what a homopolar design would look like on it. Washing machine motors look like great candidates! Look at this standard type BLDC motor!



Real easy to work with, cheap used too.

Definitely on my agenda, will try the fan motor conversion!
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