This section provides the information required to properly set up the basic parameters related to sensorless commutation of a brushless DC motor. This process involves setting the sensorless parameters on the BAC controller’s and riding the bike to determine if motor startup response and feel are agreeable to the user.
In order for a motor to run in sensorless mode, the Motor position sensor type should be set to 2.
The parameters associated with sensorless commutation are shown in the table below.
It should be noted that certain applications are not suitable for the use of sensorless commutation. For example, if the application requires that motor be started into a heavy load, a Hall sensored motor may be a better choice. Front wheel drive bikes are also a better choice for sensorless commutation than rear wheel drive systems.Motor startup response and feel is best adjusted by modifying Sensorless open loop starting current and the Sensorless closed loop enable frequency.
The crude diagram represents a motor phase current waveform to illustrate the function of each sensorless motor startup parameter.
Addition informational parameters