基于TMS320LF2407非对称采样五电平脉冲实现

通过有效利用TMS320LF2407型DSP的硬件资源,实现了SPWM的非对称规则采样,并通过采用载波相移调制策略得到五电平脉冲输出波形。对采用平均对称规则采样和非对称规则采样两种方法所得结果进行了实验对比。实验结果表明,在正弦波调制的情况下,非对称规则采样同样具有计算简单,便于在线实时运算的优点,该采样法所形成的阶梯波比平均对称规则采样更逼近正弦,调制效果更接近自然采样,能更有效地减少谐波含量。

A Asymmetry Sampling and Five-level PWM Pulse Output based on TMS320LF2407 DSP

Harmonics elimination in multi-level converter is one of research hotpots in power electronics field. In this paper,a kind of application of asymmetry sampling way in multilevel converter is introduced.Through effectively usage of TMS320LF2407 DSP,a asymmetry sampling of SPWM can be realized,and through Carrier Phase Shifted SPWM (CPS-SPWM) technique,the five-level PWM can be obtained.The contrast experiment result of the output of symmetry sampling and the asymmetry sampling shows under the sine wave modulate mode,the asymmetry sampling output is closer to the sine wave than symmetry sampling with fewer harmonics.On the other hand,the DSP processing data of asymmetry sampling way is only double of the symmetry asymmetry way and it is also simple and easy to calculate on line.Through organically combining of Carrier Phase Shifted SPWM technique with the asymmetry sampling technique,we can more effectively eliminate the harmonics other than the integral times of four times switch harmonics.Then,it is in great values of engineering application such as application in APF and SVG and so on.