Comparison of Analytical and Numerical Methods for PMSG Design Applied to D-Type Wind Generators

Abstract

The objective of this work is to perform a comparative study between analytical and numerical methods (implemented via 2-D and 3-D FEM software) in 3.88 MVA, 710 V, 145 Hz permanent magnet synchronous generator (PMSG) design with a focus on wind power generation, for D-Type wind turbines. For this purpose an analytical solving method is proposed using NdFeB surface permanent magnet rotor. After this step the analytical results were compared with the numerical results and showed results with average relative error margin of about 3% (2-D simulation) and average absolute error of 37.3 mT (3-D simulation). In the second part of the design, AlNiCo PM were used in the rotor, however, the analytical and numerical results showed high average error, making the previous method, used for NdFeB PM, not suitable, requiring changes in the method. It is proposed then, a readjustment of the PM volume calculation, through analytical and numerical methodology. For the development of the method the main contributions were the modification of the table of speeds and frequencies from 60 Hz to 145 Hz, the creation of an extension parameter for the tip of the stator tooth to refine the airgap flux density calculation and the analytical solution of the rotor design when using AlNiCo PM. After these changes, the results obtained with a calculated average error margin of about 4% were satisfactory. The analytical and numerical results were commented and presented at the end of this work for the validation of the methodologies for both of PM (NdFeB and AlNiCo).