Easy-to-Implement Integral Numerical Simulation of Multi-phase Drives under Fault Supply Condition

Abstract- This paper presents an easy way to model multi-phase electrical drives in fault supply conditions. The presented technique makes it possible to simulate the drive in various configurations with keeping the same integral model established in normal mode. Simulations of a seven-leg seven-phase drive are carried out and compared to experimental measurements. I

Multiphase induction motor drives - a technology status review

The area of multiphase variable-speed motor drives in general and multiphase induction motor drives in particular has experienced a substantial growth since the beginning of this century. Research has been conducted worldwide and numerous interesting developments have been reported in the literature. An attempt is made to provide a detailed overview of the current state-of-the-art in this area. The elaborated aspects include advantages of multiphase induction machines, modelling of multiphase induction machines, basic vector control and direct torque control schemes and PWM control of multiphase voltage source inverters. The authors also provide a detailed survey of the control strategies for five-phase and asymmetrical six-phase induction motor drives, as well as an overview of the approaches to the design of fault tolerant strategies for post-fault drive operation, and a discussion of multiphase multi-motor drives with single inverter supply. Experimental results, collected from various multiphase induction motor drive laboratory rigs, are also included to facilitate the understanding of the drive operatio

A Novel Five-Phase Fractional Slot Concentrated Winding with Low Space Harmonic Contents

In this article, a novel five-phase fractional-slot concentrated winding (FSCW) with 20-slot/22-pole is presented. It benefits not only the advantages of conventional FSCW but also weak space harmonics of magnetomotive force (MMF). The winding allows eliminating the first sub-order harmonic. The new layout of the winding topology is obtained by a combination of stator shift technique of the winding in the slots with a special coupling of the windings (star-pentagon), using winding function theory. The high performances of the new winding layout are validated using the finite element method (FEM). Compared to the conventional winding, the winding factor and the total harmonic distortion (THD) of MMF are improved by 1.3% and 2.2%, respectively. With the same injection of current density, the average output torque is increased by 1% and the torque ripple is decreased by 60%. The eddy current losses in the permanent magnets (PMs) at rated speed (600 r/min) and 2100 r/min speed are improved by 67% and 56%, respectively

Fault Tolerant Multiphase Electrical Drives: The Impact of Design

La version editeur de cet article est disponible à l'adresse suivante : http://journals.cambridge.org/action//displayFulltext?type=1&fid=8024174&jid=JAP&volumeId=43&issueId=02&aid=8024172&bodyId=&membershipNumber=&societyETOCSession=This paper deals with fault tolerant multiphase electrical drives. The quality of the torque of a vector-controlled Permanent Magnet (PM) Synchronous Machine supplied by a multi-leg Voltage Source Inverter (VSI) is examined in normal operation and when one or two phases are open-circuited. It is then deduced that a seven-phase machine is a good compromise allowing high torque-to-volume density and easy control with smooth torque in fault operation. Experimental results confirm the predicted characteristics

Multi-criteria based design approach of multiphase permanent magnet low speed synchronous machines

Version éditeur disponible à cette adresse : http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4797497&isnumber=4797494A design methodology dedicated to multi-phase permanent magnet synchronous machines (PMSMs) supplied by pulse width modulation voltage source inverters (PWM VSIs) is presented. First, opportunities for increasing torque density using the harmonics are considered. The specific constraints caused by the PWM supply of multi-phase machines are also taken into account during the design phase. All the defined constraints are expressed in a simple manner by using a multi-machine modelling of the multi-phase machines. This multi-machine design is then applied to meet the specifications of a marine propeller: verifying simultaneously four design constraints, an initial 60-pole three-phase machine is converted into a 58-pole five-phase machine without changing the geometry and the active volume (iron, copper and magnet). First, a specific fractional-slot winding, which yields to good characteristics for PWM supply and winding factors, is chosen. Then, using this winding, the magnet layer is designed to improve the flux focussing. According to analytical and numerical calculations, the five-phase machine provides a higher torque (about 15%) and less pulsating torque (71% lower) than the initial three-phase machine with the same copper losses

Two-Slot Coil Pitch For Five-Phase Integrated Permanent Magnet Synchronous Machine

This paper presents a simple method to size a concentrated winding permament magnet synchronous machine when a high number of slots is needed. A classical concentrated winding machine leads to a number of pole pairs close to the number of slots to be efficient. Thanks to a two slots pitches winding, number of slots can be doubled without deteriorate the winding factor. Moreover, this specific winding is also useful to deal with embarassing magnetomotive force harmonics. The method is detailed here for a specific case of a machine with integrated power converter. Sizing of the machine is also presented and finite element simulations results show performances of this design compared to a conventional one.This work has been achieved within the framework of CE2I project (Convertisseur d’Energie Integre Intelligent). CE2I is co-funded by European Union with the financial support of European Regional Development Fund (ERDF), French State and the French Region of Hauts-de-Franc

Sensorless Control of a Seven-phase Non-sinusoidal Permanent Magnet Synchronous Machine Using High Frequency Signal Injection Method

International audienceThis paper presents a sensorless control strategy for seven-phase non-sinusoidal permanent magnet synchronous machine (NSPMSM) with high frequency signal injection (HFSI) method in 5th harmonic subspace. Seven-phase nonsinusoidal machine benefits high torque density due to the use of third harmonic components. Firstly, two torque generation strategy in different harmonic subspaces with the minimum injected rms value and amplitude of current is deduced in this paper. Secondly, in order to reinforce the reliabilities of multiphase machine, the HFSI sensorless control is employed. Comparing with traditional HFSI method, the proposed control strategy is achieved in 5th harmonic subspace, which can avoid the torque ripple caused by the injected signal. Finally, according to simulations results the two torque distribution method is validated and compared and the effectiveness of the HFSI method is verified