针对传统三相逆变器中由于高频开关动作而产生高峰值高频共模电压的问题。首先对电机驱动系统空间矢量脉宽调制（SVPWM）与三态脉宽调制（TSPWM）下的共模电压进行对比分析，并在此基础上研究了非连续脉宽调制（DPWM1）的调制波与TSPWM的调制波之间的关系，给出了基于载波的TSPWM调制实现方法。然后，研究了正负极性载波之间的关系，给出了负极性载波在工程上的一种实现方式。最后对所提的TSPWM调制实现方法进行仿真和试验验证。结果表明，可以用DPWM1的调制波的实现方式来实现TSPWM的调制波，负极性载波下的脉宽调制（PWM）信号可以由正极性载波代替生成。

To address the problem of high peak high frequency common-mode voltage due to high frequency switching action in conventional three-phase inverters. The common mode voltage under space vector pulse width modulation (SVPWM) and tri-state space pulse width modulation (TSPWM) of motor drive system is firstly compared and analyzed, and on this basis, the relationship between the modulating waveform of discontinuous pulse width modulation (DPWM1) and the modulating waveform of TSPWM is investigated, and the method of realizing TSPWM modulation based on carrier wave is given. Then, the relationship between positive and negative polarity carriers is studied, and a way of implementing negative polarity carriers in engineering is given. Finally, the TSPWM modulation implementation proposed is verified by simulation and experiment. The results show that the modulating waveform of TSPWM can be implemented in the same way as the modulating waveform of DPWM1, and the pulse width modulation (PWM) signal under a negative polarity carrier can be generated by a positive polarity carrier instead.