secondly, the modification function and resonance produced by running power capacitor increased the harmonic at the same time, which worsen the operation environment of itself . it is very important to analyze the reason of harmonic and conduct the valid measure to restrain its affect and guarantee the safely operation of power network . the author has present the point in this paper, based on the operation characteristic of modern power system, the author described the production and development of network harmonic with the consideration on the same kind of problem 本文以现代电力网络的运行特点为基础,结合近年来对所涉及的同类问题的思考,对系统谐波的产生、发展的一般规律进行较为全面的理论阐述;以大量事故案例分析谐波所带来的危害和影响;通过实地测试和对所得数据的分析研究,推导出一种应用matlab的fft的谐波分析方法,给出了该方法的程序流程框图及结果界面显示;在此基础上进一步探讨了利用现代通信网络建立电网谐波网络管理分析系统的总体构想和功能。