Comprehensive Monitoring of Electrical Machine Parameters Using an Integrated Fiber Bragg Grating-Based Sensor System

In this paper, a multiparameter, multisensor system for comprehensive electrical machine condition monitoring has been developed and the results of an evaluation reported. The fiber Bragg grating-based system developed allows for the simultaneous monitoring of key parameters including machine vibration, rotor speed, torque, spin direction, temperature distribution along the stator windings and on the rotor surface as well as the stator wave frequency. This all-optical sensing solution has been designed to be compatible with being fitted in the tight confines of an electric motor and uses the optical nature of the measurement and the insulating nature of the sensor material to avoid problems of electrical interference. The system reduces the component count over conventional sensor systems, i.e., all sensing elements are contained within the machine and operated by a single sensing interrogation unit, thereby reducing cost and allowing for a convenient interface for the user. The design of the system is presented, as are results on the testing and evaluation of the device the sensing system has been successfully integrated into and tested on a permanent magnet motor prototype.