Achieving Low-Noise, Sensorless Field-Oriented Motor Control

The move to electronically commutated motors has seen massive improvements in energy efficiency, which in turn contributes to the reduction of both the operational cost and the amount of greenhouse gases that industry and consumer goods emit. However, this switch is not without its challenges. Brushed DC motors were able to use their brushes and slip-ring configuration to commutate the motor at the correct moment in time as this configuration also served to indicate the angle of the rotor in relation to the permanent magnets. Regardless of the rotor orientation, the coils would always be energized at the appropriate time, enabling an efficient motor start-up.