单相逆变器小波多分辨调制技术研究

Research on Single-phase Inverter Control Technology Based on Multi-resolution Wavelet Modulation

为进一步改善逆变器输出谐波的频谱分布,提出一种基于多分辨小波调制(WM)的单相逆变器控制技术。首先将逆变器调制过程模拟为一个非均匀采样与重构的过程,而后采用组合Haar小波结合多分辨分析(MRA)理论对这一过程进行实现。实验表明,与传统的正弦脉宽调制逆变器相比,这种WM方法可将逆变器输出的集中在整数倍开关频率附近的谐波相对均匀地分散到一个较宽的频带范围内,并有效减小整数倍开关频率附近的离散谐波幅值。这有助于降低因过于集中的谐波功率谱引起的系统电磁干扰(EMI)。

In order to improve the frequency spectrum of output harmonic, a multi resolution wavelet modulation （WM） for single-phase inverter control technology is presented.Inverter modulation behavior is modeled as a non-uniform sampling and reconstruction process, this is realized through a multi-resolution analysis（MRA） which is constructed by basis functions of a combined Haar wavelet.Experimental results show that,compared with sinusoidal pulse width modulation （SPWM） inverter, the frequency spectrum of output harmonic is spread to a wide frequency band from integral multiples of switch frequency, which is helpful to reduce system electric magnetic inference （EMI）.