Motor and Position Sensor Choices for QVADRANS?

I’m looking to build my own QVADRANS controller, and I’m looking to pick up a position sensor and motor combo for testing.

For the motor, I checked the documentation for sample motors, but I can’t find anything up to the 30V / 60A that the QVADRANS can theoretically output. The high performance motors recommendations are all for the sample DRV8302 board, which has a current of under 27amps. Does anyone know any affordable motors that can handle the peaks I am asking it to?

For position sensing, I was looking at the AMT103 optic encoder due to the adjustable CPR, which might be useful for motors with different kVs. However, I’m not sure if mounting the sensor to the shaft of the motor would be an issue. Does anyone know if I will have to design some sort of mechanism to attach the encoder, or know any other encoders that are easily “plug and play”, that also have CPRs that fit the range needed for high performance BLDC motors?

Please check the product documentation for the AMT model you are buying. Mine came with a bunch of little “adapter” plates to attach the sensor to different sized shafts.

(like the colourful plastic parts at the bottom of this picture)

Normally you choose the motor based on the application you want to use it in. If you’re just looking for high powered motors, then you can use any 3 phase BLDC motor you want.
Drone motors from the racing drones are available with low resistances and high current ratings, although you might want to attach a propeller to have some load and for the cooling effect - XING 5215 X CLASS FPV Motor

Or a large drone type motor like this: V505_V Type_Motors_VTOL/Fixed Wing Power_T-MOTOR Store-Official Store for T-motor drone motor,ESC,Propeller

Brushless RC-Car motors can also be very powerful: CSX Modified -V2- 540 Brushless Motor sensored 4.5T -7800kv- 1-2S - C, 79,90 € - might be a bit fast-turning 108A at 7.4V :slight_smile:

You can also get larger motors, like for mopeds: Elektro Scooter, eBikes, Li-ion Batterien und mehr - Bürstenloser Motor 48V 500W

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Thank you for the response. If I stick with lower current motors like the GARTT ML4114 which is listed as supported on the docs, would it work with the AMT103 encoder?

Sure, no reason it would not work in principle.

But in terms of the physical hardware you will have to design a connection between the motor, your load and the encoder. The encoder normally goes around the motor shaft, but this motor has only a very short “stub” rather than a real shaft, and if you attached it there the encoder would cover the mounting holes on the rotor…

image image

Seems like most of the motors in this price range have short stubby shafts. They’re also too small to have room to mount an encoder on that back. Do you know any cheap motors that have either a longer shaft or room to mount an encoder on the back?

I replaced the shaft with a longer one and printed out the housing to install the magnet and encoder. The main thing is that the engine does not have a shaft of a specific diameter, for example, 3.175 mm.

What motor is that and what shaft did you get? I might consider your route then if the swap isn’t too difficult.

In fact, this applies to any motor for which it is possible to find a long axle of the desired diameter. I had a hard time finding one for the 2212 motor, as it has a diameter of 3,175 mm.

The other two motors have an axle diameter of 5mm

I also had to rewind the 2212 motor by more turns and connect it according to the star scheme. It began to work more smoothly, consume less current and began to heat up less))

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Look good. Is a rewind necessary, or can I just directly swap out the shafts?

Also, what are the name of the motors in the picture?

As I understood. For best performance, the KV rating should be low. If you manage to find them, then there is no need to rewind. In the photo are motors 2212, 3548 and 4250