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FSESC 4.20 Tuning for RC ESC?

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Abcc123
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FSESC 4.20 Tuning for RC ESC?

Hey everyone I need some help on how to tune my FSESC 4.20. I am doing a project with my son and we have to use 20v drill batteries, that cannot change. We are using an RC ESC right now and its flying, but when I go to the FSESC 4.20 it stutters really bad. I was able to tune it so well that it was snappy and responsive w/o load, but once a load is applied it bogs and says under voltage error. I changed A settings to motor/battery but the torque grunt was not there. The VESC-Tool auto detection said it was a 13 pole motor (but its actually a brushless sensorless 4 pole (4 magnets) drill motor), and 25-30A Motor Current and 130 Absolute max. We made a 12 to1 reduction gearbox and it helps reduce the motor load so I know its working. I tried FOC and BLDC Motor type with FOC giving the best results, and Current/Duty Cycle input, Not sure which is best. The higher the Motor amp the better the result but still lacked the low end grunt. After more research I changed the Openloop setting tab to fast start as well as Heavy load and fast start was ok, but not under load. Next I am testing the PIDs after reading about how to check and get them set but I am way outside my element and trying to crash course at night. Battery current max was 99 but should be adjusted to maybe 30-45A but would that limit the Amp output to the motor?

 

Does anyone have ideas/insight on how to tune? Below is a snapshot of our RC ESC that makes quick work of it w/o lag. 

 

ESC Graph

frank
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What is the exact HW and the battery you use? 20V batteries should not exist. should either be 18V or 21,6 (5 or 6S LiIon). Depending on what you entered during setup, the ESC FW thinks you are at the lower discharge limit and cuts out. Motor poles only matter for real time data, not for how the motor runs. You can change that during setup. Just type 4 pole into the equivalent field.

Abcc123
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Thanks, I am using a flipsky 4.20 50a base on VESC 4.12. you are correct it's an 18v, I was thinking peak voltage. Do you have any tips or advice on what info I should enter/adjust? 

Mainly I adjusted FOC/BLDC and Current/Duty Cycle and max battery Amp and Motor Amp. I haven't done much with PIDs since I am still learning those. Also sensorless settings and ERPM limits. 

 

frank
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What is the motor model? Inrunner or outrunner, KV value etc.

Abcc123
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I am trying 2 motors. One is a brushless motor out of an impact drill, specs unknown. Looks to be a 4 pole inrunner. I am trying to use some charts online with a voltmeter and drill to find the specs. The 2nd is a Traxxas 10 turn Brushed motor, roughly 245 watts and 4500kv from looking at some charts online. Here is a picture of the brushless motor.