Optimization of the digital resources required for the control of electrical motors for further space use

Details

Supervisors

Dehez, Bruno ; Bekemans, Marc

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil électromécanicien

Abstract

For a few years now, Thales Alenia Space Belgium has been developing an entirely new processor called the DPC. Compared to the other processors available on the space market, the DPC has been made more resistant to radiations and is a mixed-signals controller able to generate analog signals and to convert electrical quantities into digital data. As a result, the DPC combines the advantages of different types of controllers in a single processing unit. Thanks to its flexibility and its peripherals, it meets the increasing needs for improvement in the space field. Anticipating the introduction of the DPC to the market, several potential customers have already shown their interest for this unique controller. This master’s thesis has been made with a view to meeting these customers’ interest. It aims at determining if an electrical motor control can be implemented in the DPC. There are several different types and structures of electrical motors but this master’s dissertation only analyzes one type of synchronous motors : the permanent magnets synchronous motors. The first part of the document is a small reminder concerning the electromechanical converters and especially the synchronous motors. The basic principle of these converters is described as well as the important notions which must be understood for the description of the controls. A simple model of the permanent magnets synchronous motors is also presented. Then, the interest of controlling a motor and the two main types of synchronous motors controls are also introduced (vector and scalar controls). The DPC is also presented as well as its architecture and its peripherals, which are described in order to have a better idea of its ability to perform regulation processes. The MSP430 architecture and its interesting features are presented as well. Finally, the two controls are compared and the vector control is selected in order to be implemented in the DPC. All its composing blocks are analyzed as well as the related interesting notions and principles. For instance, the fixed-point representation, the CORDIC algorithm and the SVM algorithm are presented and optimized for an implementation in the DPC. Two complete controls are then implemented in order to determine if it is possible to control a synchronous motor with this processor. It allows to conclude that it is possible to control permanent magnets synchronous motors with this controller. However, some specifications are highlighted as the maximum frequency that can be reached as well as the constraints on the motor that can be controlled.