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This paper analyzes the effects of injecting additional signals in induction machines for the purpose of speed control. A new saturation model able to correctly model the interaction between the added signal and saturation of the motor core due to the main torque-producing flux is presented. The introduction of a variable saturation factor is used to model the variation of the saturation level due to the additional signal. A third harmonic rotor circuit is also introduced to take account of the third harmonic component of the air-gap flux, due to saturation. An additional balanced voltage set is added to the normal supply to analyze the effects of such signals on a saturated induction motor. Simulation results of such a model both at no load and full load are presented together with experimental measurements. Index Terms--Air-gap flux harmonics, flux position estimation, q-d model, saturation modulation, sensorless control.

Based on the concept of the converter fed machine (CFM), an optimal machine design can be considered as the best match of the machine topology, the power electronic converter and the performance specification. To compare power production potential of axial flux machines with various topologies, different waveforms of back emf and current, general purpose sizing and power density equations for such machines are needed. In this paper, a general approach is presented to develop and to interpret these equations. Sample applications of the sizing and power density equations are utilized to compare the axial flux toroidal permanent magnet (AFTPM) machine and the axial flux two-stator permanent magnet (AF2SPM) machine.

An analysis method is developed for modeling of multi phase cage induction motors with asymmetry in the stator, arising due to an interturn fault resulting in a disconnection of one or more coils making up a portion of a stator phase winding and any distribution and number of rotor bar and end-ring failures. The approach, based on the winding functions, makes no assumption as to the necessity for sinusoidal MMF and therefore include all the space harmonics in the machine. Simulation and experimental results confirm the validity of the proposed method. Keywords: Winding Functions, Stator Failure, Broken Rotor Bars and End-Rings, Induction Machines, Simulation

It is demonstrated that the rotor design of synchronous reluctance machines can be optimized in terms of a key geometric parameter, i.e., the ratio of the rotor insulation width to the rotor iron width so as to obtain maximum torque production. The equation which gives the maximum motor power factor in terms of the saliency ratio has been derived and it is shown that the power factor of 0.8 is a realizable value with the optimal rotor design. An experimental motor has been fabricated and the results of measurements of the motor parameters prove the validity of the rotor design optimization.

In this paper, a synchronous/permanent magnet hybrid(SynPM) machine is presented. It is shown that the machine has good power density and efficiency, and that the machine has true field regulation capability. The principle of operation, finite element analysis and simulation of this new machine are investigated in the paper. Index Terms--Field weakening, hybrid, permanent magnet machine, synchronous machine.

Presents a synchronous/permanent magnet hybrid machine. Power density and efficiency of machine; Role of permanent magnet poles; True field regulation capability of machine; Principle of operation, finite element analysis and simulation of machine.

Part II. Discusses field-oriented control techniques for a multi-phase induction machine with an unbalanced stator winding structure. Multi-phase induction machine; Unbalanced operation; Unbalanced stationary to synchronous reference frame transformation for stator current.