基于解析小波变换的变压器绕组模态参数识别

电力变压器绕组的模态参数与绕组结构振动特性、动力特性优化设计及振动故障诊断密切相关，考虑到传统的模态识别方法在获取变压器绕组这类非线性系统参数时的局限性，在对某10 kV实体变压器绕组进行轴向激振实验的基础上，引入复小波变换法对测试得到的振动信号进行分析，同时使用Crazy Climber算法提取小波脊线，得到变压器绕组的前三阶固有频率及其对应的阻尼比。计算结果与目前通用的频域识别方法Poly Max法识别结果的良好吻合说明计算结果的正确性。此外，计算结果表明基于小波变换的模态参数识别方法具有较强的抗干扰性能力，适合于分析变压器绕组这类复杂结果的模态参数。

Modal Parameters Identification of Transformer Winding Based on Analytical Wavelet Transform

The modal parameters of power transformer winding are closely related to the vibration feature, optimal design of dynamic, feature vibration of winding structure. Consequently, it is of importance to accurately identify the modal parameter of power transformer winding. When considered the difficulty of obtaining the accurate results of modal parameters of power transformer winding, the axial excitation experiment of some 10kV power transformer is first made in the paper. The complex wavelet transformer is introduced and applied to analyze the measured vibration signal. The algorithm of Crazy Climber is selected to extract the wavelet ridge. Then the first three natural frequencies and its damping ratio are obtained successfully. The well agreement between the results calculated by the complex wavelet transformer and the results calculated by the frequency domain identification method of PolyMAX which is currently widely used is illustrated the effectiveness of the proposed method. Furthermore, it is shown that the proposed method has strong anti-interference feature and could be applied effectively to identify the modal parameters of transformer winding. Calculated results could provide theoretical foundation for the vibration analysis method to detect the winding condition.