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Myxa Field weakening

Hello guys !

I’m using the Myxa 0B with telega v0.2 for a quad copter UAV.
I’m very please with the ESC controler and its small SWAP.

I’m using a lithium-ion battery (full charge: 25.2V - empty: 18V) and due to it’s low empty voltage (compare to a classic lipo : empty voltage ~20.5V) the motor can’t deliver the require rotation speed I need when the battery is 2/3 deplete.
I would like to use that remaining third but to keep control of the UAV the motor need to be able to reach a maximum speed of 5400RPM. From my test I can reach that maximum rotation speed with an input voltage of 21V (Motor KV = 487).

To reach 5400 RPM at 18V, would it be possible to use the field weakening function ? Is it recommendable for a multi-copter ?
How can I use it correctly ? It look like it required some attention (Max current/watts power data sheet discrepancy)

From this post Voltage Utilisation Factor telega v0.3 has a better maximum phase value (amazing news !), so updating the firmware would improve this problem ?

Thank you for your answer.

Hi Hadrien,

The field weakening can be used for a short-term significant increase in thrust during extreme maneuvers. However, it is not recommended using this mode unless absolutely necessary, as it greatly decreases energy efficiency. It is better to take a motor with a high KV value.
In your case, I would recommend trying the new v0.3 firmware first. The speed range should increase by about 10%. It depends of course on the propeller and the amount of load on the motor.

Thank you Dmitry for the answer, I’ll try the new v0.3 firmware first and change the propulsion if required.