AC IM Vector Control (FOC)
Vector control (also called Field-Oriented Control, FOC) is a method used in variable frequency drives to control the torque and thus finally the speed of three-phase AC electric motors. In particular, the method implies the measurement of motor currents and successively their transormation into a coordinate system rotating with the rotor of the machine. In order to perform this reference frame transformation, rotor position has to be directly measured (through actual speed/position sensors) or indirectly estimated (sensor-less approach).
Vector control requires HW peripherals to be up of this task and more intensive computation compared to scalar controls, on the other side it provides better dynamic responses (e.g. to load change in speed control), more accurate machine torque regulation and often more silent operations.
Usually cost-effective 32-bit microcontrollers can handle this type of drive.
UM0486: STM3210B-MCKIT motor control starter kit
Publications and Collaterals
Standard MCU simplifies efficient motor control