水力机组振动监测中的信号预处理

Signal Pretreatment of Hydraulic Power Unit Vibration Monitor

水力机组振动复杂 ,信号呈现出非线性、非平稳性。因此 ,振动信号的预处理在水力机组振动监测中非常重要。小波变换由于其良好的时域、频域局部化特征、尺度变化特征和方向特征 ,在众多学科领域取得了广泛的应用。文章针对小波变换应用于水轮机的振动监测进行了研究 ,并利用其多尺度多分辨率的特点对监测信号进行分解 ,然后按照一定规则对各尺度系数处理后进行重构 ,通过对仿真数据的计算 ,达到了较好的效果。

It is very important for the signal pretreatment of hydraulic power vibration monitor because the situation of vibration is complicated, and the signal appears non-linear and non-stable character. Small wave changing method possesses upstanding character of time-frequency field localizing, scale changing and direction, and obtains extensive application in numerous scientific region. The paper makes investigation of adopting the small wave changing method in the vibration monitor process, and using its multi-scale and multi-resolution character to decompose the monitor signal, then treating with each scale coefficient according to definite rule and reconstructing, through calculating the emulation data and obtains favorable effect.