Analysis of the Solid Iron Rotor Induction Motor for Solid-State Speed Controls

Experimental Loss Segregation in a Solid Rotor Induction Motor

“…Both the rotor resistance and reactance vary with slip, and the leakage reactance is numerically equal to half of the resistance, meaning a constant rotor phase angle of 26.6°and power factor of 0.895 [21]. This model has been extensively used for the fundamental frequency effects in SRIMs [4], [7], [22], [23], while the linear approach has been adopted mostly to study the smallsignal behavior of harmonic field components [24]- [26]. The absence of rotor laminations offers a free path for the circulation of high-frequency eddy currents, which arise mainly from the non-sinusoidal distribution of the stator magnetomotive force (MMF), from the non-uniform airgap permeance due to the slot openings and from time harmonics eventually present in the power supply [9].…”

“…Solid rotor induction motors (SRIMs) are asynchronous machines whose rotor is a simple solid steel cylinder that acts both as magnetic and electric circuit, sometimes also featuring longitudinal slits and copper end rings, bars or superficial layers [1], [2]. Some of their advantages over laminatedrotor motors are their higher mechanical strength and thermal ruggedness, simpler manufacture, lower starting current and higher starting torque per ampere [3], [4]. These characteristics make SRIMs well-suited for applications at higher speeds or with severe load cycles [1], [4], [5].…”

“…Some of their advantages over laminatedrotor motors are their higher mechanical strength and thermal ruggedness, simpler manufacture, lower starting current and higher starting torque per ampere [3], [4]. These characteristics make SRIMs well-suited for applications at higher speeds or with severe load cycles [1], [4], [5]. Applications are found in gas compression [2], [3], [6], railway traction [7], medical [8] and generation [5] contexts.…”

“…Different approaches for iron loss calculation were studied in [13], whose results are verified with test results only at no-load condition. The experimental procedure followed in other works [4], [6], [8], [14], [15], was limited to locked-rotor and no-load tests.…”

Effect of Harmonics on a Solid-Rotor Induction Motor

“…Fourier analysis show that inverter waveform contains many harmonics, when compared with old rotary converters. The solid-rotor motor has a significant advantage over conventional cage-rotor motors, when used in conjunction with solid-state drives [Leo A. Finzi, 1968]. Its rotor impedance have a numerical value which depends strongly on the magnitude of the voltage applied to the stator terminals for any given frequency [Leo A. Finzi, 1968].…”