Moteur sans balais | EPFL Graph Search

Un moteur sans balais, ou « moteur brushless », ou machine synchrone auto-pilotée à aimants permanents, est une machine électrique de la catégorie des machines synchrones, dont le rotor est constitué d'un ou de plusieurs aimants permanents et pourvu d'origine d'un capteur de position rotorique : capteur à effet Hall, synchro-résolver, codeur rotatif (par exemple codeur incrémental), ou tout autre système permettant l'auto-pilotage de la machine. Fonctionnement Vu de l'extérieur, il fonctionne en courant continu. Son appellation (de l'anglais brushless) vient du fait que ce type de moteur ne contient aucun collecteur tournant et donc pas de balais. Toutefois un système électronique de commande doit assurer la commutation du courant dans les enroulements statoriques. Ce dispositif peut être, soit intégré au moteur pour les petites puissances, soit extérieur sous la forme d'un convertisseur de puissance de type onduleur. Le rôle de l'ensemble capteur plus électronique de comma

Solar Impulse – Thermal simulation of the electronic circuit board

Laurie Saunders

The goal of this semester project is to create a thermal model of a electronic circuit board that will be used to control a Brushless DC motor for the project “Solar Impulse”. For this project, the finite element (FEM) software Ansys is used to build the model and to then apply the thermal loads. The software will calculate the temperature of the circuit board. The modeling using FEM is applied as it is not possible to make an analytical model for a complicated configuration like in this case.

2004

Analyse et conception de moteurs synchrones chemisés à commutation électronique

The number of brushless DC (BLDC) motor applications has increased significantly, essentially due to reduced costs of semiconductors and permanent magnets, but also because of the emergence of new control strategies, such as closed-loop and sensorless control. Among the different electric drives, the heating circulation pump is a typical application which could greatly benefits from new BLDC technologies. Nowadays, the majority of low power heating circulation pumps is driven by AC induction motors. Despite of its low efficiency (< 20% for a single phase motor and < 50% for a three phase motor), this kind of motor is still used widely, because of its inherent simplicity since no electronic driver is needed. When a regulation is necessary (for example pressure, flow regulation), this advantage disappears. The aim of this work is a systematic analysis of the circulating pump motor. One solution is investigated in particular: the pump with a sealed BLDC motor. The following points are analysed in details: An analytical method to calculate the flux density distribution is tailored for motors with an important gap, as the sealed motors or slotless motors. The analysis of the electromagnetic characteristics for brushless DC motors shows the similarity of the various brushless DC motors. The calculation of tube losses determines their influence on the energetic balance of the motor. The determination of the acoustical motor noise shows the influence of the different modes of phases switching. The thermal aspects which take into account the motor environment are examined from the theoretical and practical point of view. The synthesis of these points results in a concept for the design and optimisation of BLDC motors; a series of pump prototype have been designed. For the heating circulation pump, the replacement of the AC induction motor with a brushless DC motor makes it possible to double the global installation efficiency. This solution is very promising from an energising aspect as well as an economical one and contributes to electrical energy savings, essential in this end of century.

EPFL1998

Flux Observer-Based vector control for Induction Motor

Sébastien Allemand

The induction motor offers the best value for money and is therefore used in many different application fields where power requirements are higher than a few kilowatts. ln order to be able to reduce the priee and the motor's size, a control algorithm based on an estimation of the flux without speed sensor for a Brushless AC motor (BLAC) has been developed in the Professer Shen's lab. The objective of this project is to examine the possibility to adapt and then implement this sensorless control algorithm to the induction motor. The induction motor's specificities will have to be analysed carefully in order to be able to propose an adapted control solution which will be implemented and tested on an induction motor.

2013

Analyse et conception de moteurs synchrones chemisés à commutation électronique

EPFL1998