Self-monitoring smart motors
Simply using data collected from the self-monitoring motor while it is operating, researchers can calculate quantities that in other systems need to be measured by bulky sensors. Moreover, they have ‘taught’ the drive how to make use of this knowledge to make its operational processes more efficient and reliable. Researchers with the EU-funded project OFS-MOTOR (Optical fibre based self-monitoring motor drives) worked on an elegant way of extracting the greatest possible quantity of operational data. The aim was to equip the motor with advanced diagnostic and prognostic tools. Since conventional sensors have limitations in terms of insulation required for working with high electromagnetic interference and space constraints, as well as added weight, the project has offered technological innovation. This is realised by four optical fibres, each carrying 12 sensing points, (fibre Bragg gratings), integrated into the motor stator and rotor. The fibre sensor system collects measurements of key parameters. These include real-time measurements of temperature of rotor and stator, vibration, torque, rotational speed and position stator wave frequency as well as spinning direction. Data obtained are subsequently analysed to identify hot spots and faults and calculate the process’s energy efficiency. Before the end of OFS-MOTOR, researchers demonstrated the success of shifting from an electrical to an optical sensing approach on a test bed. The ‘smart’ motor drive together with conventional sensors and their data logging systems was put to the test. The results provided clear evidence that fibre Bragg gratings as sensing elements can replace conventional bulky sensor systems prone to electromagnetic interference issues. More data gathered from the motor will aid in efficient and reliable control in aerospace applications.
Keywords
Smart motors, motor drive, OFS-MOTOR, optical sensing approach, fibre Bragg gratings
