Field Oriented Circuit (FOC) vector motor control varies the voltage across the phases depending on the desired speed and rotor position. FOC allows precise control of the voltage and current in the phases of the motor to achieve optimal operation.
In general, FOC uses a coordinate transformation to convert the three-phase voltage into two components: a current component along the rotor (Id) and a current component along the poles (Iq). The phase voltages are then calculated to produce the desired current components Id and Iq.
The FOC attempts to follow a given speed or rotor position by adjusting the corresponding current components. The phase voltages are calculated based on the current values of current, rotor position and controller settings. This is done by adjusting the phase shift and amplitude of the phase voltages.
This way, the motor phase voltages will dynamically change according to the required operation and requests of the FOC controller to achieve optimum speed and motor control.
