关于电网供电电能质量优化检测研究

Research on Power Quality Optimal Detection of Power System

在电网电能质量的检测中,电力系统谐波是一项重要的检测内容,如何准确检测出谐波频率、幅值和暂态发生的时间是检测的难点.为解决上述问题,提出一种新的改进S变换算法。改进S变换是在原S变换的基础上,用频率的对数代替原函数的频率,并增加一个参数调节时频分辨率,从而提高检测精度。为了验证改进S变换算法的有效性,通过理论分析和MATLAB进行仿真,能够有效检测出频率、幅值以及时间等信息,将获得的结果与理论值和基于原始S变换的结果进行对比,表明改进S变换在电力系统谐波检测中具有很好的时频分辨率,且检测值更加准确。

In the detection of power quality of the power system, the harmonic of power system is an important part, and how to accurately detect the harmonic frequency, amplitude and transient time is the difficulty of detection, a new modified S - transform is proposed. The modified S transform is on the basis of the original S transform, and is established by replacing the frequency with the logarithm of the frequency in the original Gaussian window function and a parameter is added to adjust the time -frequency resolution,thus the detection precision is improved. In order to verify the effectiveness of the modified S transform, through theoretical analysis and MATLAB simulation, the characteristic information such as the harmonic frequency, amplitude, and the starting and ending time in the transient state can be effectively extracted, and it is shown that the modified transform has better time - frequency resolution and more accurate readings in transient harmonic detection than the original S transform.