To tackle the challenges of uneven capacitor voltage in the propulsion setup of a three-phase permanent magnet servomotor driven by a T-type three-level inverter, a direct torque control strategy based on zero-sequence voltage injection with carrier modulation is proposed. Firstly, the direct torque control strategy is constructed by motor model calculation. Secondly, the modulation voltage involved in pulse width modulation (PWM) control is obtained by coordinate transformation from the expected voltage, which realizes the combination of carrier modulation and direct torque control. Finally, in order to realize the balanced control of the midpoint potential, the zero-sequence voltage injected is calculated and corrected according to the sampling difference of the upper and lower capacitor voltages. The experimental data demonstrates that the suggested control approach effectively achieves a reduction in torque fluctuations and maintains balanced control of neutral point voltage.