Field-Orientation Control of Three-phase Permanent Magnet Synchronous Motor Control under healthy and open-circuit fault Conditions

Abstract

Permanent magnet synchronous motors (PMSMs) are widely used due to their simple structure, high performance, and simple control strategies. Over the years, several control techniques have been developed in motor control, whereas vector control, which is also called field-oriented control (FOC), has had great success in PMSM control. The concept of FOC is that the motor torque and flux are decoupled from each other, which means they can be controlled separately. Since torque control is achieved by the speed controller, it can be considered that the speed and the flux of the PMSM are also decoupled from each other and can be controlled separately. As a result, vector control of a three-phase PMSM using decoupled flux and speed control is proposed in this work. The FOC scheme is used, and separate flux and speed regulators are proposed. In addition, two control methods are applied. The first method is based on the proportional-integral (PI) controller, while the second method is based on the proportional-resonant (PR) controller. As a result, decoupled speed and flux control of three-phase PMSM based on the PI control method and decoupled speed and flux control of three-phase PMSM based on the PR control method are proposed.

In addition, a comparative study of PMSM torque control using PI and PR control methods is undertaken. The study compares the motor performance of the PMSM based on each method and the complexity of the overall control scheme.

Also, the behavior of the PMSM is studied under the open circuit fault condition. Hence, vector control of PMSM based on a PR controller under an open-circuit fault is studied. During the fault situation, it is challenging to guarantee the continuous operation of the motor, achieve good steady-state and dynamic performance, and reduce the ripple in the speed and flux response. However, the PR control method proves its efficacy in controlling the PMSM under OCF conditions.