To investigate the effects of time-harmonic current introduced by inverter on loss characteristics of fractional-slot concentrated-winding permanent magnet synchronous machine (FSCW-PMSM),a method is proposed to analyze the harmonic characteristics of losses of the machine in inverter and FSCW-PMSM combined system. Firstly,the time- and space-harmonic characteristics of losses considering time-harmonic current are theoretically analyzed. Then,a 10-pole and 12-slot PMSM with three-phase double-layer winding is taken as an example. The field-circuit co-simulation model of the prototype and space vector pulse width modulation (SVPWM) inverter is established,the harmonic characteristics of losses are calculated under constant torque and constant power speed control,and the causes of each harmonic loss are revealed. The results show that rotor harmonic losses are caused by fundamental current with sub-harmonic,iZ±p slot harmonics,and (f_c±4f)/f,(f_c±2f)/f time-harmonic current with p,Z±p space harmonics. Stator core harmonic losses are caused by fundamental magnetic field,magnet harmonic excitation magnetic field and (f_c±4f)/f,(f_c±2f)/f time-harmonic current. The conclusions can be applied to the FSCW-PMSMs with other pole-slot combinations. Finally,the proposed method is validated by experiment results.