中文摘要：

传统方法为了产生多电平电压,往往需要每个H桥单元都有一个独立对应的半周期对称三角载波,且不同载波之间有一个固定的移相角度。而对基于锯齿波的载波移相技术研究的较少。为此,提出了一种基于锯齿波的载波移相脉冲宽度调制（pulse width modulation,PWM）技术。与传统方法相比,在该方法中,所有功率单元都使用同一个载波作为时间参考,并使用非对称PWM发生器来产生传统的对称的载波移相PWM波形。采用数字信号处理器（digital signal processor,DSP）芯片TMS320F2812对一个5单元11电平进行载波移相试验,采用所提的锯齿载波移相PWM技术实现方法,仅通过事件管理器就可以对5单元变换器提供开关脉冲。试验结果验证了所提方法的正确性和有效性。

英文摘要：

In order to produce multilevel waveform,each H-bridge cell is modulated by utilizing independent half-period symmetric triangular carrier.We put forward a new carrier-phase-shifted（CPS） PWM strategy on the basis of Sawtooth carrier wave.Compared with the traditional CPS method,only one carrier is used as time reference for all cells in the proposed method.A symmetric CPS PWM waveform is generated by asymmetric PWM generator based on the continuous up-counting mode.A five-cell（eleven-level） converter is controlled by using the proposed technique based on a TMS320F2812 DSP controller.Event manager module itself can generate the gating pulses for five cells by using the proposed method.Experimental results validate the effectiveness of the proposed control algorithm.