Automatic control of synchronous motor using PI controller for improving power factor

Abstract

This paper proposes a method to improve power factor of electrical system by automatically
controlling the synchronous motor. The PI control methodology is proposed for controlling the synchronous
motor in order to excite rotor field with constant power factor. The PI control scheme is managed by using
LabVIEW program on computer. Moreover the data acquisition card (DAQ USB-6009) is used for connection
between the software and hardware. The results showed that the responses of the PI controller which tuned by
Ziegler-Nichols have the ripple problem of the field current control. The problem is solved by using the Ziegler-
Nichols method worked together with the trial and error method. The performance of the Ziegler-Nichols
method worked together with the trial and error was highly satisfactory in order to optimize an operating point
of synchronous motor control to improve power factor automatically.