A simple fault-tolerant control method for open-phase three-phase induction motor drives

Abstract

Fault-Tolerant Control (FTC) strategies for Three-Phase Induction Motors (TPIMs) against an open-phase fault have attracted considerable interest in safety-critical applications. In the available literature, open-phase FTC methods for TPIMs are typically implemented using suitable Current Transformation (CT) and Voltage Transformation (VT) matrices. However, the controller design becomes complicated due to different transformations. In addition, the model based on CT and VT suffers from slow dynamics due to several Proportional–Integral (PI) controllers. This paper proposes an open-phase FTC technique for TPIM drives with proof of its asymptotic stability. It is designed based on a new CT for stator current components. Using this CT, the traditional vector control method can be used for Open-Phase TPIMs (OPTPIMs). Furthermore, considering that parameters of the PI controller have an important effect on the OPTPIM drive performance, a design technique is presented to achieve the best values of PI controller parameters. Additionally, an open-phase fault detection technique is presented based on the third-difference operator. The proposed FTC has a simple structure and fast dynamic responses. Matlab simulation and experimental results using DSP/TMS320F28335 approve the ability and good performance of the introduced FTC technique for TPIM drive systems under different conditions.