An Enhanced Fault-Tolerant Control of a Five-Phase Synchronous Reluctance Motor Fed From a Three-to-Five-Phase Matrix Converter

Abstract

A five-phase fault-tolerant combined star-pentagon synchronous reluctance machine (SynRM) can provide a high torque density, minimal torque ripple, and superior fault tolerance. To enhance the performance of SynRM in the case of an open-circuit fault, this article proposes an optimal current angle to maximize the torque and minimize the torque ripple under the fault condition. The drive system consists of a five-phase combined star-pentagon SynRM fed from a three-to-five-phase matrix converter (MC). When determining the operating point of maximum torque per ampere (MTPA), the influence of fault and saturation on the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$d$ </tex-math></inline-formula> - and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$q$ </tex-math></inline-formula> -axis inductances is considered. The healthy phases’ currents are reconstructed to guarantee a null value of zero-sequence current. Space vector modulation is applied to control the MC under the fault condition. Under the fault condition, the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$z$ </tex-math></inline-formula> -subspace is properly controlled to reduce the overall harmonic distortions of current. Moreover, the performance of the drive system is analyzed using the finite element method (FEM) simulation and MATLAB program. Finally, the experimental tests validate the effectiveness of the suggested approach on a SynRM prototype drive system with a three-to-five-phase MC.