谐波干扰下逆变器并联系统同步控制数字信号输出方法

摘要

In the presence of harmonics , the traditional synchronous control digital signal output method of har-monic frequency offset , waveform distortion , the output signal of poor synchronization of defects , therefore , the synchronous control of digital signal output , a new method of parallel inverter system was proposed .Harmonic inter-ference was suppressed by fractional Fourier method .Taking two inverters parallel system to supply the same load , for example , the working characteristics of parallel inverter system are studied .The parallel system of different in-verters obtains the phase error by sampling the signals shared in the synchronous bus , and synchronously controls the output of the sinusoidal reference digital signal according to the acquisition error .In the process of synchronous control, frequency control is added so that the frequency of different inverters is kept at the level of steady state fre -quency .The experimental results show that the proposed method can effectively guarantee the synchronization of digital signal output , and has strong practicability .%在谐波干扰下,传统同步控制数字信号输出方法存在谐波频率偏移、波形畸变大、输出信号同步性差的弊端.为此,提出一种新的逆变器并联系统同步控制数字信号输出方法.通过分数傅里叶方法实现谐波干扰抑制.以两个逆变器并联系统向相同的负载供电为例,对逆变器并联系统的工作特性进行研究.不同逆变器并联系统通过采样同步总线中共享的信号,求出相位误差,依据获取误差对正弦基准数字信号输出进行同步控制.在同步控制的过程中添加频率控制,使得不同逆变器的频率保持在稳态频率的水平.实验结果表明,所提方法能够有效保证数字信号输出的同步性,实用性强.