Automated System for Diagnostics of Emergency Operation Modes of Electric Motor

The article provides basic information on the development of a diagnostic and indicate system for the emergency operation of powerful unregulated AC electric drives in real time. Existing protection systems in electric drives are insufficient to detect the emergency operation of electric motors at an early stage of their generation. The presence of a nascent emergency mode is diagnosed by slightly increased stator currents and by the occurrence of additional pulsations and harmonics of the reverse sequence in the current signals. The consideration of such factors for the protection of the electric motor leads to the appearance of a large number of false alarms of protection and, hence, to the instability of the operation of the electric drive. The article gives an analysis of the electrical and mechanical losses characterizing the operating mode of the electric drive. The cause-effect relations are revealed that allow determining the optimal set of physical quantities, the measurement and control of which allow one to estimate with a required accuracy one or another mode of operation of the electromechanical system.