The neutral-point voltage oscillation due to the modulation method is analyzed first for the three-level neutral-point-clamped（NPC）traction inverter.Then，the characteristics of the neutral-point voltage oscillation and the total harmonic distortion（THD）of load current due to two traditional space vector pulse width modulation（SVPWM）methods are compared with each other，respectively.On the basis of this，a SVPWM method with adjustment of neutral-point hysteresis-loop width is proposed to balance the neutral-point and reduce the THD value of load current.Finally，both the amplitude of neutral-point oscillation and the THD value of load current are compared and analyzed via MATLAB/Simulink simulation and dSPACE hardware-in-the-loop experiment when the three modulation methods are adopted.Simulation and experimental results show that the adopted SVPWM method with neutral-point loop width control is efficient for balancing neutral-point voltage and reducing the THD value of load current.