摘要:针对单相桥式逆变器的三种SPWM载波控制方式进行了理论分析,采用单倍频调制实现简单,有效抑制了谐波和减少了开关损耗,提高了输出效率。在此基础上对单极性、双极性和单极性倍频单相SPWM逆变电路输出电压含有的低次谐波进行了仿真计算,提出了有效的谐波抑制策略,重点介绍了滤波器的设计,并根据需求设计了LC滤波器,并就逆变电路加滤波系统进行了Matalab仿真验证,最后介绍了利用DSP实现单倍频SPWM的方法并设计了一个逆变器,实验结果证明,该方案正确可行,输出波形良好。 关键词:逆变器;谐波抑制;滤波设计;DSP Abstract: In this paper, three kinds of SPWM carrier control mode of the single phase bridge inverter were analyzed in theory, using double frequency unipolar modulation will be able to restrain the harmonics, reduce the switching loss and improve the efficiency of the output obviously. on the basis of this, a simulation of voltage output with the lowest harmonic content for a single phase of unipolar, bipolar and double frequency unipolar SPWM inversion circuit were made. The effective harmonic suppression strategies were presented. According to demand, a design of the LC filter was done, and then the inverter circuit with filtering system carried on the simulation analysis by Matalab. Finally, the use of DSP to achieve double frequency unipolar SPWM method and design an inverter, the experimental results show that the scheme is correct and feasible, and the output waveform is fine. Key words: inverter power; harmonic suppression; filter design; DSP
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