光伏发电超高次谐波发射特性及影响因素分析

由电力电子装置广泛应用带来的超高次谐波问题近年来引起关注,但光伏发电超高次谐波发射特性的研究仍不够充分。本文首先以采用双极性调制的典型电压源型逆变器为例分析其产生的谐波幅值及分布规律,确定了产生超高次谐波的直接影响因素:开关频率、调制比、直流侧电压;然后重点分析了滤波器参数、控制器参数、MPPT控制以及不同功率水平对超高次谐波的间接影响,给出了LCL滤波器参数选择依据;基于某光伏系统的实测数据,对光伏发电超高次谐波主要频率分布范围及总体含量进行量化分析。最后,基于Matlab/Simulink搭建了光伏发电系统的仿真模型对上述分析结果进行验证。

Analysis of Ultra-high Harmonic Emission Characteristics and Influence Factor of Photovoltaic Power Generation

In recent years,the issue of ultra-high harmonics due to wide application of power electronic devices has attracted attention,while,the study on the characteristics of ultra-high-harmonic emission of photovoltaic power generation is still insufficient.In this paper,its generated harmonic amplitude and distribution law are analyzed by the use of typical voltage source inverter using bipolar modulation as an example and such direct affecting factors generating ultra-high harmonics as switching frequency,modulation ratio and DC side voltage are defined.Then,the indirect influence of parameters of filter,controller,the control of MPPT and different power levels on the ultra-high harmonics is analyzed emphatically,and the basis for selecting LCL filter parameters is given.The main frequency distribution range and overall content of ultra-high harmonics of photovoltaic power generation is quantitatively analyzed on the basis of the actually measured data of certain photovoltaic system.Finally,a simulation model of photovoltaic power generation system is set up based on Matlab/Simulink to verify the above analysis results.