AC MACHINES-1 (66761) Theory
Completion requirements
2. Perceive the emf equation, transformation ratio and Losses of transformer.
2.5. Interpret Hysteresis loss, Eddy current loss, Core loss and Copper loss.
What is eddy current loss and hysteresis loss?
Eddy current loss= The ohmic losses in a metal body, due to the eddy currents flowing through it, induced by an alternating magnetic field. Hysteresis loss= The loss in form of heat when magnetisation of the material is made to alternate with respect to time.
What is hysteresis current loss?
Hysteresis loss is caused by the magnetization and demagnetization of the core as current flows in the forward and reverse directions. As the magnetizing force (current) increases, the magnetic flux increases. ... Therefore, when the magnetizing force reaches zero, the flux density still has a positive value.
How is hysteresis loss calculated?
dB‟ is the area of elementary strip of B –H curve shown in the figure above, Therefore, Energy consumed per cycle = volume of the right x area of hysteresis loop. The hysteresis loss per second is given by the equation[20]: Hysteresis loss, Ph= (Bmax)1.6f V joules per second (or) watts.
Conclusion: hysteresis Losses can be reduced by special core material which reached to zero or near zero flux density after removal of current. Eddy current Losses can be reduced by making core by thin sheets by reducing the area of each Eddy current branch.
What do you mean by eddy current loss?
Eddy current loss is conductive I2R loss produced by circulating currents induced in response to AC flux linkage, flowing against the internal resistance of the core.