kubark42
1 W
- Joined
- May 15, 2020
- Messages
- 61
I have a 3-phase motor where the individual coil leads are very easily accessed at the star point and phase leads. It is a 42 pole, 36 tooth, 20kW, 380A motor which has test data showing 94% efficiency at 20kW.
I am wondering whether it would be practical to cut the leads where the coils join the star point and the phase leads and then to reorganize them to make effectively two electrically independent 3-phase motors, but mechanically 30 degrees apart and in the same casing. While there are already hall sensors, the plane is to drive it in sensorless current control mode, using an ESC on each 3-phase.
The application is a propeller, so there is no need for position control, fast response time, low speed torque, or high-speed field weakening.
The goals are twofold:
I feel like this ought to work, but I don't fully understand the ramifications of two ESCs acting in the same casing. Will the magnetic fields from one ESC perturb the sensorless feedback of the other? Will efficiency take a hit?
I am wondering whether it would be practical to cut the leads where the coils join the star point and the phase leads and then to reorganize them to make effectively two electrically independent 3-phase motors, but mechanically 30 degrees apart and in the same casing. While there are already hall sensors, the plane is to drive it in sensorless current control mode, using an ESC on each 3-phase.
The application is a propeller, so there is no need for position control, fast response time, low speed torque, or high-speed field weakening.
The goals are twofold:
- Higher redundancy than can be achieved with only a single ESC
- Easier sourcing of ESCs (there's a much wider choice of battle-tested 200A controllers than 400A controllers)
I feel like this ought to work, but I don't fully understand the ramifications of two ESCs acting in the same casing. Will the magnetic fields from one ESC perturb the sensorless feedback of the other? Will efficiency take a hit?