Hybrid excitation synchronous motor control in electric vehicle with copper and iron losses minimization

This paper presents an optimal current control for the hybrid excitation synchronous motor in electric vehicle application. The control aims to meet the torque and speed requirements while insuring minimal copper and iron losses. Extended Lagrange multipliers optimization method (Kuhn-Tucker conditions) is used to elaborate analytical expressions for the optimal reference armature currents as well as for the field current i_f with respect to armature current and voltage constraints. Simulation over the new European driving cycle proves that the proposed optimal control leads to the lowest losses compared to the results obtained by other synchronous motor control strategies.