Saturation and space harmonics in the complex finite element computation of induction motors

Computation of Wound Rotor Induction Machines Based on Coupled Finite Elements and Circuit Equation Under a First Space Harmonic Approximation

“…The background of the electromagnetic model is the same as the one described in [6]- [7] for squirrel cage induction motors. The machine is split into two domains of resolution noted Ds and Dr, Fig.1.…”

“…This allow to adapt the first harmonic approximation to the physical situation of a given problem. A discussion on the subject can be found in [7].…”

“…The magnetic field is truncated so only the principal air-gap space harmonic is considered. A similar approach has been successfully used for the computation of squirrel-cage induction motors [6]- [7]. A FE computation is needed for each value of the slip frequency in the rotor bars.…”

Computation of the effect of Space Harmonics on the Performances of a Cage Induction Motor Using Time Harmonic and Time Stepping Methods

“…The double air-gap method and the interface coupling method are used to compute the speed-torque and the speedcurrent characteristics of a 4-pole induction motor which has about 60% of 7 th harmonic and 35% of 5 th harmonic [1]. The study is performed for a speed range [-1500, +1500] (rpm).…”

“…The first method we have developed uses the double air-gap method [1] and considers that the saturation is mainly due to the first space harmonic. The second method [2] uses an interface coupling and takes into account the saturation due to all the considered harmonics.…”