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Increasing phase amps beyond 300a on 100-250

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reubarb.scons
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Increasing phase amps beyond 300a on 100-250

Hi,

I have a QS138 with a VESC 100-250
Vesc tool is preventing me from selecting higher than 300a phase.

It does not give any help as to if this is an artificial limitation or current sensor limitation.

There is a setting under FOC > Advanced > High Current Sampling mode.

Would this allow me to run higher phase current? 

Frank seems to say that he has been running over 400a on a gokart a few years back

There is another option which is the no HW limits FW but I would rather not go for that option if possible.

In two days time I will be taking the scooter to the dyno so that I can tune the motor well and see actual output power.

So far I am peaking at about 15kw input power according to my BMS. 

Any help appreciated,

Reuben 

frank
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The 100/250 should not be operated beyond 300a. Maybe with modifactions and additinal cooling you can pus 350A for a short time.

The 75/300 can take more with good cooling, but you can't go that high in voltage. So output power wise both units are equal if you opt for max possible voltage.

reubarb.scons
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What is the reason for being unable to go beyond 300a? 

I can easily keep the unit cool and the motor is far from saturation.
I understand there will be much more losses through the mosfets from here up but surely an extra 50a will not be too bad.

Either way, the scooter is going on the dyno tomorrow and I would like the ability to run higher phase current than 300. 
How can I make it do this? 

frank
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To do that you need to load the No Limits FW.

reubarb.scons
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Okay, so I have loaded the no hw limits fw and put it on the dyno.

All I have changed is the phase current and lowered the observer gain to 1

At 420 phase amps it puts down 30 wheel horsepower. It's shockingly fast with this many amps. Now heat is becoming an issue but I'll rig up a good cooler solution in a couple of weeks. For now I have the ESC temperature limitation low