Measurement system for circulating stator currents: Towards condition monitoring of large MW-scale synchronous motors

摘要

This article discusses a sensor system enabling the acquisition of circulating stator currents in the case of an industry-scale motor. The focus during development of this condition monitoring system was to achieve high measurement. fidelity and, at the same time, to provide a robust and flexible sensor system which is suited for final installation in a factory environment. The layout of the sensor system as well as constraints imposed by the motor environment will be discussed. Typical circulating currents recorded with the sensor setup show a complex and rich frequency spectrum caused by the high sensitivity of the method which indicates even small asymmetries in the synchronous motor.