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This paper introduces PeMSyn, a free tool intended to aid the design and simulation processes of permanent magnet synchronous machines. Using PeM-Syn, one can effortlessly design a permanent magnet synchronous machine, design its winding distribution and assess the machine performance. The machine performance is evaluated by means of FEA since PeMSyn provides an interaction between Matlab and FEMM. Thus, several machine parameters can be obtained. Another interesting characteristic of PeMSyn is its modularity, which means that each functionality can be run independently and new functionalities and machine topologies can be added either by the user or by means of a new PeMSyn update. Aiming to be simple and user-friendly, PeMSyn was coded in Matlab language in form of a graphical user interface (GUI). Moreover, users can easily translate all labels and variable names to their mother language using a language description file already available in English and Portuguese. The modules, the machine design process, the equations involved and an application are shown in this paper. In order to present guidelines on how to use PeMSyn, an example of machine design is proposed and its performance is assessed.

One of the main obstacles during the design of permanent magnet machines consists in reducing the developed torque ripple characteristic of this type of machine. The main component of such ripples is a parasitic torque, called cogging torque. A technique present in the literature to reduce this parasitic torque considers the segmentation of the poles. This allows a decrease in the cogging torque, however reducing the air gap flux density too and thus the torque mean. Thus, in order to keep the torque mean reduction in reasonable levels, optimization techniques can be employed with the pole segmentation. The variables to be optimized are the number, distance and width of the segments. The present article proposes two methods to optimize these variables in order to minimize the cogging torque, but also maintain a satisfactory flux density value. Some constraints are added to account for the machine construction feasibility. The proposed methods were validated through a nite element analysis. The results proved the effectiveness of the proposed methods, with a reduction by up to 76% in the cogging torque and keeping, in the best case, about 95% of the reference machine air gap flux density and 78% in the worst one.

Torque ripples can cause mechanical stress in electrical machines, among otherproblems. The present paper proposes three methods to reduce these ripples in the permanent magnets synchronous machine considering rotor poles design. These methods consist in segmenting the rotor poles, with width and distances between segments obtained by SPWM techniques. The modulating wave is a sinwave which has the same frequency as the air gap flux density fundamental harmonic. Method 1 contemplates the unipolar SPWM technique, whereas methods 1 and 2 used the bipolar SWPM technique. Furthermore, the equations used to predict the cogging torque behavior are presented and verified by means of a finite element analysis. The torque ripple reduction is achieved due to the elimination of back-electromotive force harmonics and the decrease in the cogging torque peak. Method 1 has proved to be the most effective, reducing the torque ripple by 51.38% and 76.61% for the 4-pole and 8-pole machines, respectively. In addition, the magnet volume utilized has been reduced by 22.55% for the 4-pole machine, but the average torque value has been reduced by 18.7%. It is worth mentioning that the proposed methods do not require skewing to reduce the torque ripple.