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Influence of hanging load on induction machine torque and stator current in hoisting winch system

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Abstract

The aim of this paper is to analyze theoretically and experimentally the stator current and the load torque of a three-phase induction machine in a hoisting winch system in order to show the influence of hanging load at different levels in motoring modes. In this paper, the results of hanging load are verified in time and time-frequency domains and it has been observed that in case of fast changing of the load, it introduces a non-stationary oscillation during a short time. This leads producing a low frequency component in both the output torque and the stator current spectrograms with different levels of hanging load.

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