Effects of System Harmonics and Unbalanced Voltages on Electromagnetic Performance of Induction Motors

Various phenomena can deteriorate the performance of induction motors and cause potential safety hazards. This can be harmful for the respective applications. Deficiencies like unbalanced voltages due to an unbalance in the power grid or harmonics in the voltage source could result in problems like excessive losses, over-voltages, mechanical oscillations, and interference with control electronics. Detecting these abnormal conditions in the machine is of great importance in the interaction of the electrical machine and the power grid. In this paper the effect of the unbalanced voltages and harmonics on the motor performance, have been investigated. Then, monitoring these unhealthy condition using electrical machine parameters is carried out. In this case motor itself can act as the sensor that detects unpopular condition.