Compensation of the current measurement error with periodic disturbance observer for motor drive

Output current of general inverter is controlled based on the information of current sensors which are placed on the output. However, these sensor outputs have gain error and offset which are depending on the peripheral components and the accuracy characteristics of current sensor. Current control performance can be deteriorated a control method which uses a periodic disturbance observer to suppress vibration. We have developed a periodic disturbance observer as a control method for vibration suppression. Focusing on the current sensor error, it may cause the vibration of a specific frequency. Then, this paper proposes a current sensor error compensation control method by applying a periodic disturbance observer. To suppress the harmonic current online by this approach, the current control performance can be improved.