Electric power consumption, has been increasing uninterruptedly, being this increase specially accelerated in the last years. New power generators are been built, the installed power increases each year, thus it is necessary a way to transmit the bulk energy. Nowadays electric lines are saturated, they are reaching critical values of ampacity and sag. Therefore building new lines is necessary to provide the ever increasing consumption.The difficulty to find corridors to construct new overhead lines is increasing in industrialised countries and in many cases it is simply impossible. It is not easy to obtain the rights of way for new transmission lines. The construction of new overhead electric lines is increasing difficulty, thus there is a need to look at alternatives that increases the power transfer capacity of the existing right of ways. This circumstance is forcing the use of the existing lines, which represents a cheaper solution than making an underground transmission.

The influence of various types of windings on the cogging torque and the total torque developed by a three-phase permanent magnet synchronous motor (PMSM) is investigated. The number of poles and rotor geometry are fixed and the stator slot number is modified. The finite element technique is used for the computation of the machine characteristic. The torque is determined by means of the Maxwell stress method. It is shown that the optimizing the cogging torque to a low value is therefore not sufficient to obtain a low torque ripple.

Abstract. Influence of the slot opening width and rotor pole radius on the cogging torque and total torque developed by a three-phase permanent magnet synchronous motor (PMSM) is investigated. The number of motor poles and number of stator slots are fixed. Finite element technique is used for the computation of machine characteristic. Core saturation is directly considered in the magnetic field calculation. Formulation based on two methods, virtual work and Maxwell stress tensor is used to find the torque.

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Abstract. This work analyzes influence of manufacturing tolerances on permanent magnet synchronous machines (PMSM) behaviour. These tolerances result in imperfections in both final geometry of the machine and composition of material characteristics. The finite element method is used to calculate cogging torque and torque ripple.