Page - 109 - in Hybrid Electric Vehicles

The PMSM with outer rotor (PMSMOR) (see Figure 3) is one of the special topologies of PMSM, with some advantages for BSAB applications: • Belt mounted directly on the outer rotor, without using pulley. • Easy mounting of permanent magnets, the centrifugal forces do not influence their me- chanical stability. • High torque capabilities. • Convenience of cooling, etc. The development cycle of PMSM (inner or outer rotor) topologies includes analytical proce- dure, magnetic field analysis and optimization procedure connected to previous design steps. The analytical procedure is presented in detail in Refs. [13, 14] and includes the following top- ics: analysis of the specifications, selection of the topology, the active and passive materials, sizing the machine, choice of the manufacturing technologies and information about prelimi- nary cost evaluation. In the dimensioning procedure, classical formulas or dedicated software platforms like SPEED software can be used. The electromagnetic flux analysis is realized with dedicated programs (like Flux 2D/3D, Jmag 2D/3D, Maxwell 2D/3D, ANSYS, Opera, open-source programs, etc.) based on the finite ele- ment method (FEM). The FEM is a widely used method for obtaining a numerical approxi- mate solution for a given mathematical model of the machine. The obtained results are related to the voltage/current waveform, map of flux density, electromagnetic torque, losses (iron and Joule), and the efficiency value or map of it. The optimization of electric machine is a multivariable, nonlinear problem with constraints. In order to treat problems with constraints, it is necessary to transform them into unconstrained ones. This can be done, for instance, by embedding the constraints in the objective function. Figure 3. PMSMOR type. Performance Analysis of an Integrated Starter-Alternator-Booster for Hybrid Electric Vehicles http://dx.doi.org/10.5772/intechopen.68861 109