As environmental concerns grow globally, the necessity to reduce polluting emissions is of key importance to the survivability of the automotive industry. The continuously rising number of vehicles that employ hybrid or fully electric powertrains leads to the need for more efficient electric machines. The most commonly used type of electric motor in the vehicular application field is the permanent magnet synchronous motor, thanks to its high power-density and efficiency. When implemented in a vehicle, the electric machine is fed by a PWM supply, whose harmonic content increases the power loss of the motor. The scope of this research is to improve the accuracy of the iron loss prediction in permanent magnet synchronous motors fed by PWM supply, employed in traction applications.