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Disable regenerative braking


I work on the definition of a new Tethered UAV and I am thinking of using Myxa ESC. But our power supply cannot take any reverse current.
Is it possible to disable regenerative braking on Myxa or will we have to design a protection system to dissipate energy coming back?


You can control the regeneration yourself by switching to the current control mode. In this mode, regeneration will not occur unless you commanded a negative setpoint. This will obviously affect the dynamics of the system though, as the controller will no longer be able to extract kinetic energy from the rotor to achieve faster response. If this is undesirable, you will likely need to implement an energy absorber on the vehicle, perhaps in the form of a small battery.

Thank you for your answer, this is interesting. I will see what we can do.

we tried it with switching to the current control mode , but still observe energy flowing back to the Lipo at higher RPM.
We tested it with 2 Motors , Motor nr.1 was physically connected to Motor nr.2 , Motor nr.2 had also Myxa ( in current control mode ) and we observed when driving Motor nr.1 , the Myxa on Motor nr.2 is still putting out some Voltage , we where even be able to charge the lipo connected to Myxa on Motor nr.2 .

What was the current setpoint on the second Myxa during this test? What current did you observe on its DC link? What was the supply voltage provided to it?

the setpoint on the second Myxa was 0 , we obseverd a voltage increase on the second Lipo around 6000rpm of the second Motor

If the setpoint was zero from the start, Myxa was likely residing in the idle state, not driving the motor at all. In this mode, the inverter acts as a passive three-phase rectifier. If the magnetic flux linkage in the motor is sufficiently high and the battery voltage is sufficiently low, you will observe a reverse current flow from the motor to the battery, but this mode is not representative of the normal operation because the controller is idling.

For a proper test, you will need to either run one motor independently (without the second one), or ensure that the second Myxa is not in the idle mode.

Oh, so much useful stuff here, we just need to figure it out.