Commutation is the method used to direct current through the phases of a three-phase motor. There are two types of commutation – trapezoidal (six state) or sinusoidal.
Trapezoidal Commutation: current flows through only two phases at a time and is directed based on Hall sensor feedback.
Sinusoidal Commutation: all three phases must be sinusoidally synchronized by the drive to provide a constant torque. Current is directed through all three phases using the position feedback from an encoder.
For more information, read the ‘Trapezoidal vs Sinusoidal Commutation‘ technical article.