The efficiency of an electrical powertrain impacts several properties such as the vehicles range or the cooling requirements. Therefore, the loss in inverter and PMSM must be precisely calculated during the design process. In this paper the analytical calculation of PWM phase currents is combined with FE simulation to calculate the AC winding loss, permanent magnet eddy current loss and core loss. Additionally, the switching and conduction loss of the inverter and the loss due to air and bearing friction are included. The calculated and measured efficiency is compared at different DC-link voltages.