一种级数混合运算产生SPWM波新方法

A novel methed forming SPWM wave based on series hybrid algorithms

提出了一种产生正弦脉宽调制波的新方法。介绍了采用级数混合运算产生数字化正弦波数据的基本原理,不需要专门的ROM存储器,利用传统查表法就能够得到所需要的SPWM信号。基于所提出的方法设计了一种通用型SPWM波形发生器,利用FPGA内部的RAM资源例化成所需要的虚拟ROM存储器,用来存储由级数混合运算得到的1/4周期数字化正弦波数据,然后利用中心对称和轴对称运算得到整周期的正弦波,与三角形载波进行比较后输出SPWM信号。实验结果表明,该SPWM发生器具有可靠性高,电路结构简单,使用灵活等特点。采用所提出的方法设计的SPWM光伏逆变器已投入应用,性能良好,工作稳定。

A SPWM waveform generation method is presented. The principle of series hybrid algorithms which generates the digital sinusoidal waveform data was introduced. The SPWM signals were generated by the traditional look-up table method without the need for ROM memory. The general SPWM pulse gen- erator was designed based on the proposed method. The virtual ROM was built by RAM resource in the FPGA, which was used to store the 1/4 periodic digital sinusoidal waveform data obtained by the series mixed operation algorithms. Full cycle digital sinusoidal waveform data were produced by the operation of the center symmetry and axis symmetry. The SPWM signal was produced by the intersection between tri- angle carrier and sinusoidal. The experimental results show that SPWM pulse generator has the character- istics of high reliability, simple structure,and flexible use. The SPWM PV inverter designed by the pro- posed method is with good performance and stable operation.