基于TMS320F2812的载波移相PWM发生器的设计

Design of Carrier Shift PWM Generator Based on TMS320F2812

适用于单元级联型多电平电路的载波移相PWM调制方法,其实现的关键在于如何实时产生多路移相PWM控制信号。研制了基于TMS320F2812的PWM脉冲发生器,通过事件管理器硬件实现与CPU软件实现相结合,在DSP的各个GPIO复用管脚输出多路移相PWM波形。基于该脉冲发生器,完成了单相级联七电平逆变器的载波移相实验。实验结果表明,该脉冲发生器简化了多电平硬件电路的设计,算法程序简洁,实时性强,易于扩展。

In the implementation of carrier phase-shift PWM modulation for cascaded multi-level inverter,the key is how to generate real-time phase-shift PWM signals. A PWM pulse generator based on TMS320F2812 is presented,by means of method of the event manager hardware generation is combined with the CPU software generation,it can generate enough multi-channel phase-shift PWM signals in the associated GPIO pins in DSP. The experiment of single-phase cascaded seven-level carrier phase-shifted PWM inverter based on the generator was carried. The experimental results confirm that the design can simplify the hardware and the algorithm of multi-level inverter,the system has real-time characteristics and can be expanded easily.