A new criterion for rotor broken bar fault diagnosis in line-start and inverter-fed induction motors using Hilbert-Huang transform

This paper proposes a novel criterion for precise diagnosis of rotor broken bar fault in squirrel-cage induction motor at different operating modes. The criterion is extracted from the energy value of the Hilbert-Huang transform of the faulty motor current. Impact of the line-start and direct torque control modes are investigated at different fault levels, load torques and reference speeds. The new saturated winding function method is also used in order to include the non-linear characteristic of the motor core materials.