基于 DSP 产生的 SPWM 波的谐波估计与分析

摘要

针对2000系列 DSP 产生的正弦脉宽调制(Sinusoidal Pulse Width Modulation,SPWM)波,使用傅里叶级数模型,提出了将改进的粒子群优化(Improved Particle Swarm Optimization,IPSO)用于各次谐波的幅值和相位的参数估计方法,着重分析了在不同的调制波频率和电压下,载波比与谐波总畸变率(Total Harmonic Distortion,THD)之间的关系,通过大量的实验,得到在一定范围的调制波频率和电压下,均能保持高次谐波较小,从而得到高质量的正弦输出。这一结论不仅对 SPWM 的产生起指导作用,而且对要求正弦交流电的用电设备有着降低高频损耗与节能的重要实际意义。%In this paper, generating Sinusoidal Pulse Width Modulation(SPWM)wave based on Digital Signal Processor(DSP) of 2000 series, using the Fourier series model, this paper presents a method of estimating the parameters of amplitude and phase of harmonics according to an Improved Particle Swarm Optimization(IPSO). It discusses the relationship between carrier ratio and Total Harmonic Distortion(THD)based on difference of frequency and voltage of modulation wave. Through a large num-ber of experiments, higher harmonic is made smaller in the case of frequency and voltage of modulation wave within a certain range, hence, it makes the sinusoidal output high quality. This conclusion gives the direction how to generate SPWM wave, also plays practical significance in the electrical equipments of sinusoidal alternating current which are required to reduce high-frequency loss and energy conservation.