Pierre's 170W in 1600W out Looped Very impressive Build continued & moderated

[Jeg]

Hi Luc
I saw and translated Pierre's reply on your newest video he was asking what are you doing with your coils "return" and said this is the secret if you want it to work.
So will guess he means the backemf/recoil/flyback diodes...

If this was the case we could do it with just a simple coil wrapped on a simple core. But IMHO this is not the case and never was. 

[pmgr]

Hi Gotoluc,

How did you connect the L298N boards, as H bridges, or as half bridges?

Regards

L192

Please see attached image for how they are hooked up. Red is output 1-2 of H-bridge, black is output 3-4 of H-bridge.
PmgR

[T-1000]

Continuing on alternator conversion - http://www.pirate4x4.com/tech/billavista/Wiring/Part2/


Pierre's simulated field movement makes three phases around stator. If we make output coil in same way as in alternator and have 3 overlapping coils on stator with outputs from each junction this would complete the cycle. Then just create 3 phase switching around 36 (3x12) stator coil contacts and take output on stationary rotor.


Would be really interesting to see what you guys could get on output...

[listener191]

My connection scheme is a little different, I only switch one half bridge at a time on the same board. This reduces the heat dissipation on each L298N.
Also I use the enable lines to switch the transistors, so the high and low side transistors float when enable is low

I achieved a reasonable rotor output waveform until I pushed the setup too hard at about 4A per half bridge. This was after about 20 mins of running. This took out at least 5-6 boards, after one L298N exploded. No heatsink was over about 40 deg C.

I had done this before without problem however , this time we have the shorted coils due to the overlap. In each coil line you could see the overlap current step.

I rechecked all connections and drive signals, everything appears to be in order. There were no apparent voltage spikes on the power +rail. Each board had its +/- power lines taken from a distribution strip with heavy duty cable linking to the super caps.

I have  three spare boards but  I am thinking that I will use relays next.

Disappointed but not surprised.

L192

[T-1000]

I achieved a reasonable rotor output waveform until I pushed the setup too hard at about 4A per half bridge. This was after about 20 mins of running. This took out at least 5-6 boards, after one L298N exploded. No heatsink was over about 40 deg C.

L192

If you use just few coils instead of 12 in series for single phase it will take lots of amps and will be energy waste.
Also if you watch Pierre's video and see how coils are made they are overlapping just like in car alternator and can be used with 3x12 sets.

EDIT: In Pierre's video I noticed 5 overlapping coils when started from 1st then counted to 5th position going back to stator.