[Dr_C2]

I just connected a commercial brushless driver module to one of my 4300KV sensored brushless motors.

This module measures 32mm x 32mm so far too large as a full solution but great for quick proof of concept trials.

The commercial module drives the sensored motor beautifully. At the lowest setting the slotcar wheels rotate at about 1 revolution per second (60rpm) maybe even less. As the drive signal is increased the motor spools up very smoothly. At very high rpm the tyres start to expand due to ‘centrifugal’ force. Clearly the wheels need to have a flat surface and tyres glued.

This early effort is based on bench testing and not track level testing. That said, it has already demonstrated some useful points:

1/ it’s easy to establish correct wiring for the three Hall position sensors of a brushless motor.
2/ the motor is well controlled across a wide range of rpm as required for digital slotcars. This approach provides better low speed control than standard brushed motors and a high end which is beyond what most tracks will ever require.
3/ on the bench the motor runs very cool and with no discernible vibration.
4/ this approach also provides a tacho output without any additional design effort or additional hardware. This, too, is a ‘nice-to-have’.

I now have the rest of the summer (or longer if needed) to design a very small driver module and to optimise decoder firmware. I’ll report back in due course when both have been achieved :)

c

(apologies - one detail aboved needed correction … to 1 revolution per second).