【作者】 王波；

【导师】 杨洪耕；

【作者基本信息】 四川大学 ， 电力系统及其自动化， 2006， 硕士

【摘要】 电力从它的诞生开始，就显示了作为一种重要能源的强大力量。在现代社会中，电力更成为了不可缺少的主要能源。然而随着各种电力电子设备，非线性负荷在电网中的广泛应用，电能质量的问题成为现在用户以及供电部门非常关注的问题之一。高质量的电能对于保证电网和电气设备安全、经济运行，提高产品质量和保障居民正常生活有着重要的意义。 为了提高和改善电能质量，必须对电能质量问题进行诊断、定位和分类。而如何准确快速的检测与定位电力系统波形畸变、扰动或故障的发生和恢复时刻成为电能质量扰动检测以及故障分析的首要问题。本文借鉴经验模态分解(EMD—Empirical Mode Decomposition)方法的思想提出一种电能质量扰动快速定位的新方法—三角模态检测方法。该方法通过在原始扰动信号上叠加一个三角模态分量来保留扰动信息进而定位扰动。同时，针对三角模态分量的特点，对所提方法进行简化和改进，使得所提方法能够更加简单、准确、快速地实现扰动定位。仿真结果验证了所提方法的有效性。 电力系统短时电压扰动被公认为是影响许多用电设备正常、安全运行的最严重的电能质量问题，因此对它的检测和识别具有重要的理论意义和现实意义。基于提出的三角模态检测方法，本文又提出了短时电压扰动检测的改进HHT方法。该方法是在对扰动信号进行三角模态准确定位的基础上，采用分段HHT方法对扰动信号进行分段基波幅值包络提取来实现扰动类型的识别。仿真结果表明该方法较HHT方法具有更高的检测效率。 同时，在对改进HHT方法的进一步研究中发现：Teager能量算子(TEO)更多还原

【Abstract】 Electric power shows powerful strength as a kind of important energy sources from its birth. In contemporary society, electric power even becomes an indispensable energy sources. However, with the widely use of various kinds of power electronics devices and nonlinear loads in power network, the problem of power quality becomes one of the problems which is paid attention for by customers and power supply department. High quality electric power has a fatal significance for guaranteeing electric devices’ safely and economically operation, improving products’ quality and guaranteeing normal life of the residents.To improve power quality, we have to diagnose, localize and classify the power quality problem. However, how to detect and localize waveform distortion and the start and end of disturbance or fault becomes the prime problem of the detection of power quality and the analysis of fault. In this paper, a new method based on the idea of EMD (Empirical Mode Decomposition) for the fast localization of power quality disturbances — Triangle Mode Method is presented. This method reserves the disturbance information of signals through superposing a triangle mode on the original signal to localize disturbance. And aiming at the characteristics of the triangle mode, an improved and simplified method of it is also presented, which makes the proposed method localize disturbance more simply, exactly and rapidly. Simulation results prove the effectiveness of the proposed method.Short-term voltage disturbances in power system are known as the most serious更多还原