Optimal control of interior permanent magnet synchronous integrated starter-generator

This paper deals with the optimal control of interior permanent magnet synchronous machine (IPM) in the integrated starter-generator (ISG) application. IPM designed for flux-weakening operations are able to realise high performances. Nevertheless, the ISG environment imposes lots of constraints which must be taken into account in an appropriate control. After a presentation of machine design, ISG constraints and control structure, models of the IPM and its environment are detailed including electromechanical calculations. An optimal control (total losses minimisation) based on a numerical, non linear constrained optimisation routine is described. Efficiencies in torque vs. speed plan point out the importance of taking into account voltage and power limitations against the operating range. The presented simulation results shows that Interior Permanent Magnet machine (IPM) is a good solution for ISG applications.