【摘要】 详细阐述不同载波方式对PWM逆变器输出特性的影响。指出三角载波用于硬开关PWM逆变器时 ,由于死区时间的影响 ,其输出电压电流在基波频域中含有谐波成分 ;软开关PWM逆变器如果也采用三角载波 ,则不但难以控制谐振电路的起振时间 ,而且谐振电路损耗大 ,直流电压的利用率低 ;硬开关PWM逆变器采用锯齿载波调制 ,必将导致严重的电流波形失真 ;软开关PWM逆变器交替使用正负斜率锯齿载波 ,不但谐振电路的起振时间容易控制 ,而且不会导致由死区时间引起的输出电压电流波形的失真更多还原

【Abstract】 In this paper the influence of different carrier waveforms on the output characteristics of PWM inverter is described in detail.When a triangular carrier waveform is used in hard switching PWM inverters,there will be harmonics in the neighborhood of the output frequency of the inverter output voltage and current due to the dead time. The triangular carrier waveform used in soft switching PWM inverter will cause difficulties in controlling resonance trigger time,higher loss in the resonant circuit,and lower usage of the DC bus voltage.If a saw tooth carrier is used in hard switching PWM inverter,there will be severe distortion in the current waveform.When saw tooth carriers with alternative positive and negative slopes are used in soft switching PWM inverters,the resonance trigger time is easy to control,and distortion in the output voltage and current caused by the dead time will not appear.更多还原