Dsp Based Impelementation of Field-Weakening on Synchronous Motor for High Speed Operation
No Thumbnail Available
Date
2011-01
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
Permanent magnet motors have high efficiency and torque density compared to induction and
conventional synchronous motors in general. However, in applications requiring wide speed
range, the air-gap field, which is produced by the permanent magnets, can’t be controlled
directly to control the back-emf of the motor for field weakening operation. In conventional
synchronous machines the excitation current can be controlled to control the field and hence the
speed.
This thesis presents development of field weakening control for Permanent Magnet Synchronous
Motor (PMSM) using demagnetizing component of stator current. The control is implemented
using Texas Instruments’ TMS320LF2401A Digital Signal Processor (DSP). The control method
presented relies on the field orientated control (FOC) together with a field-weakening operation.
The field-weakening operation is required to extend the speed in the constant power range of
operation, where there is no more voltage adjustment possible to increase the speed.
The field oriented control of the motors has been modeled, simulated using MATLAB and Some
of the modules of field oriented control are tested practically and results are given in this thesis.
The results demonstrate that the speed of the PMSM can be extended in the constant power range
for applications requiring wide speed range like in electric vehicle.
Description
Keywords
Speed Operation