Exciter Field Winding Temperature-Based Condition Monitoring Method for Brushless Synchronous Machines

Although the provision of excitation power is a critical aspect to the operation of brushless synchronous machines, there is no technical development in specific condition monitoring methods for exciter field windings. Exciter field windings can be affected by various faults, such as interturn faults due to insulation failures or electrical continuity losses due to connection failures. In order to provide a specific condition monitoring method for these windings, in this paper a novel method is presented based on the comparison of the measured winding resistance and winding temperature at each operating point with respect to a healthy temperature-resistance characteristic. The applicability of the method has been confirmed through experimental tests on the exciter of a 4900-kVA alternator, obtaining promising results.