摘要
传统三电平空间矢量脉宽调制(SVPWM)算法中含有大量的三角函数并且获取输出电压谐波的方法易受仿真步长、噪声、精度等影响。针对三电平空间电压矢量的分布特点,在120°坐标系下分析三电平变流器的SVPWM与正弦脉宽调制(SPWM)算法的本质联系,由此总结规律:简单的线性计算就可得到SVPWM算法的三相调制波和占空比的计算公式,从而简化了三电平SVPWM算法;针对数字电路的特点,通过傅里叶分析得到输出电压基波和各次谐波幅值的表达式,为滤波器的设计、不同调制算法的比较、进一步的理论分析和计算等提供理论基础。数字信号处理器(DSP)硬件实验证明了所提算法的正确性。
The traditional three-level space vector pulse width modulation(SVPWM)algorithm is hard to implement for the numerous trigonometric functions contained.What's more,the traditional method of acquiring output voltage harmonic of three-level inverter is susceptible to noise,step size and accuracy of simulation.Based on the distribution characteristics of three-level voltage space vector,an analysis is made of the essential relation between three-level inverter SVPWM and sinusoidal pulse width modulation(SPWM)algorithm under the 120°coordinate system.The three-phase modulation wave and pulse duration ratio are obtained just by simple linear calculation,simplifying the three-level SVPWM algorithm.According to the characteristics of digital circuits,the fundamental and harmonic amplitudes of the output voltage are obtained by Fourier analysis,providing a theoretical basis for the filter design,comparison of different modulation algorithms,further theoretical analysis and computation.The results of theoretical analysis are consistent with digital signal processor(DSP)hardware based experimental results.
出处
《电力系统自动化》
EI
CSCD
北大核心
2015年第12期130-137,共8页
Automation of Electric Power Systems
基金
国家重点基础研究发展计划(973计划)资助项目(2014CB046306)~~
关键词
三电平变流器
空间矢量脉宽调制算法
谐波分析
120°坐标系
three-level converter
space vector pulse width modulation(SVPWM)algorithm
harmonic analysis
120°coordinates
