本研究所使用的磁性編碼器的磁鈕安裝於後出軸上,而霍爾感測器安裝在定子上,因此安裝時會有偏心誤差。為了提高伺服控制時的精度,本研究將對磁性編碼器的偏心誤差建模及校正,從而得到更準確的角度值。 ;The purpose of this research is to investigate the servo drive control of three-phase synchronous brushless motors. The control hardware utilizes the ATmega128 microcontroller, along with the corresponding driver circuitry for motor operation. Fixed-point arithmetic is employed instead of floating-point arithmetic to accelerate computation and increase control frequency.
The control loop design adopts a dual-loop feedback approach, incorporating current feedback and magnetic field angle feedback. The current feedback is implemented using a PI controller, while the magnetic field angle feedback employs an I controller with a forgetting factor. This design effectively regulates the motor operation.
The magnetic encoder’s magnet used in this research is mounted on the motor′s back output shaft, while the magnetic encoder sensor is installed on the stator. Due to potential eccentricity errors during installation, modeling and calibration of the encoder′s eccentricity error are performed to enhance the accuracy of angle measurements in servo control.