Closed Loop Animation
In contrast to conventional stepper motor controllers where only the motor is actuated or the position is adjusted via the encoder, sinusoidal commutation controls the stator magnetic field via the encoder as in a servo motor. In this operating mode, the stepper motor acts as nothing more than a high pole servomotor, i.e. the noises and resonances of classic stepper motors vanish. Because the current is controlled, the motor can no longer lose any steps up to its maximum torque.
If the controller recognizes that the rotor is falling behind the stator field due to overload, adjustments are made to the optimal field angle and by increasing the current. In the opposite case, i.e. if the rotor is running forward due to the torque, the current is automatically reduced so that current consumption and heat development in the motor and controller are much lower compared to normal controlled operation.