PWM逆变器混合扩频调制技术  

A Hybrid Spread Spectrum Modulation Technique for PWM Inverters

作　　者：齐琛[1] 陈希有[1] 牟宪民[1] 

机构地区：[1]大连理工大学电气工程学院,辽宁省大连市116024

出　　处：《中国电机工程学报》2012年第24期38-44,8,共7页Proceedings of the CSEE

基　　金：国家自然科学基金项目(50877007)~~

摘　　要：针对周期性和混沌性调制无法兼顾限制扩频范围与降低谐波峰值之间的矛盾,提出一种新的混合调制方式,并将其应用于三相脉宽调制(pulse width modulation,PWM)逆变器中。该方式以频率被logistic混沌序列调制的三角波作为调制信号,不仅具有周期性调制限制扩频范围的能力,而且具有混沌性调制有效降低谐波峰值的优势。根据线电压的傅里叶级数展开式,分析扩频调制原理并得到扩频调制后谐波电压的表达式。利用该表达式,通过仿真直观地研究周期和混沌性调制频谱分布特点,在此基础上阐述混合调制原理。最后,建立实验平台,将混合调制后的线电压频谱与周期和混沌性调制后的线电压频谱对比,证明本文提出的混合调制技术的有效性。To overcome the shortcomings that periodic and chaotic modulation methods were unable to limit spread-spectrum range and suppress harmonic peak at the same time, a novel hybrid modulation technique for three-phase PWM inverters was proposed. The triangular waves whose frequency was changed by logistic chaotic sequences were taken as modulation signals, not only to gain the ability to restrict spread-spectrum like periodic modulation method, but also to obtain the advantage of reducing harmonic peak like chaotic modulation method. Spreading spectrum schemes were analyzed and a calculation method of harmonic voltage was proposed on the basis of Fourier series expansion. Making use of this expansion, spectral characteristics of periodic and chaotic modulation were intuitively studied by simulation, and then hybrid modulation schemes were explained. At last, an experimental platform was established to measure and compare line to line voltage spectrums between hybrid, periodic and chaotic modulation. The experimental results verify the efficiency of the proposed hybrid modulation technique.

关 键 词：扩频调制 逆变器 混合调制 边频带 峰值 

分 类 号：TM461[电气工程—电器]