【作者】 王凤阳；

【导师】 彭秀艳；

【作者基本信息】 哈尔滨工程大学 ， 控制理论与控制工程， 2003， 硕士

【摘要】 变电站是输变电系统的重要环节，其自动化实现了对变电站内的主要设备和输、配电线路的自动监控和保护，以及与控制中心通信等综合性的功能。因此，数据采集作为变电站自动化系统信息来源的主要手段，具有十分重要的研究价值。另外，为了保证生产、生活的顺利进行，对于电力系统中的故障必须能够及时发现和切除。 论文对变电站数据采集进行研究，采用高速数字信号处理器完成交流采样工作。对于电力系统这种实时性要求较高的场合，采用DSP对信号进行处理既能获得较好的实时性，又能降低成本。 小波分析是近年来发展起来的一种用于处理非平稳信号的分析方法。小波变换具有良好的时频局部性，具有变焦距的特点，对故障信号中的奇异点能够准确识别，是论文中应用的主要分析方法。 小波方法要在实时系统中得到应用，需要较快的计算速度，论文中对快速小波变换也有说明，并给出了一种快速算法，与常见的Mallat算法具有同样的效率。 对于电力系统故障信号的分析，本文应用Lipschitz指数对奇异点进行识别，并在论文中给出了仿真计算例子。对于采集到的信号中含有的噪声，论文中用一个实例说明了去噪的方法及效果。更多还原

【Abstract】 Substation is very important in power transmission and transformation system. Substation automation has some functions such as supervisory control and protection for main equipment and transmission or transformation line, as well as communication with control center. So, as the main ways of information source in substation automation, data acquisition has a very important value to study. On the other side, it should be find and remove the fault in time in the power system in order to guarantee the smooth manufacturing and life.In this paper, data acquisition methods in substation have been studied. DSP was adapted to complete AC sampling. In the case of power system, real time performance is needed. DSP has a lower cost and good real time performance.Wavelet analysis is a kind of method to process non-stationary signal in these years. Having good time-frequency localization character, and correctly identifying singularity point in fault signal, Wavelet is the main analysis method in this paper.Fast wavelet transform was explained in order to applying wavelet methods in real time system. A kind of fast algorithm was given in this paper and it has the same efficiency as Mallat algorithm.In this paper, Lipschitz exponent method was applied to identify the singularity in power system fault signal analysis and a simulation example was given in the last chapter. A de-noise example was list to explain how to remove noise from signal.更多还原