Open-Phase Fault Modeling for Dual Three-Phase PMSM Using Vector Space Decomposition and Negative Sequence Components

Abstract

Post-fault modeling for dual three-phase permanent magnet synchronous motors (DTP-PMSMs) under the open-phase fault is presented in this article. By using the positive and negative sequence components for the dual three-phase system, the stator currents under the open-phase fault can be treated as a combination of the positive and negative sequence currents. By artfully constructing the negative sequence components in terms of the different initial angles and amplitudes, the single-phase open-circuit fault and certain dual-phase open-circuit fault can be represented. Based on the conventional and modified vector space decomposition (VSD), only the positive sequence components are projected into the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha \beta $ </tex-math></inline-formula> subspace, namely, the torque-producing subspace, and the negative sequence components are transformed into the harmonic subspace. With the conventional proportional–integral (PI) current regulators, the dc components of the positive and negative sequence currents can be readily controlled under the open-phase fault. Experiments based on a DTP-PMSM prototype verify the effectiveness of the proposed open-phase fault modeling using VSD and negative sequence components.