摘要
为了更好地检测绕组变形,该文提出了一种用伪随机M序列激励的试验方法(M序列法)。采用伪随机M序列信号源来激励绕组,用递推最小二乘算法等直接从同时采集的激励和响应信号中获取绕组传递函数的解析表达式,利用传递函数的系数、所包含的零极点来描述绕组状态,进而通过分析他们的变化来判断绕组机械结构变化。研制了综合M序列法和频率响应分析法的绕组变形检测装置,并在饼式绕组上设置了三种模拟绕组变形的故障,对M序列法和频响法进行了试验对比。结果表明:二法在公共频段的频率响应吻合且统计特征相当,说明它们具有同等的精度;M序列法获得的传递函数系数和零极点变化能反映绕组变形,从零极点分布图中可直观地观察到一些故障类型和故障位置的信息,试验验证了M序列法用于辨识绕组变形的可行性。现场实验研究显示,二法在公共频段的频率响应吻合,传递函数的零极点和频响曲线的峰谷存在差异。该方法的研究验证了其可行性,相对频响法有优势,为进一步的实际应用奠定了基础。
In order to detect winding deformation better, a test method to by using pseudorandom binary M-Sequence excitation signals was proposed in this paper. The pseudorandom M-Sequence source was used to excite the winding, and the excitation signal and the corresponding response from the winding were combined to obtain the analytic expression of the winding＇s transfer function by using a Recursive Least Square method. The coefficients, poles, and zeros of the transfer function can be used to describe the winding status, and mechanical changes in the winding can be therefore detected. A detecting instrument for winding deformation synthetically based on the M-Sequence method and Frequency Response Analysis （FRA） was developed. Three kinds of the artificial failures aimed to simulate winding deformation were set in a pie-type winding. Comparative experiments between the M-Sequence method and FRA were carried out. Results show that frequency response and statistical characteristics of the M-Sequence method are consistent with those of FRA in the common frequency band, which proves that the two methods have the same accuracy in terms of frequency response. Transfer function coefficients obtained by the M-Sequence method as well as changes in the map of the poles and/or zeros can also indicate winding deformation. The experiments confirm that the M-Sequence method is a feasible approach for identifying winding deformation. Moreover, the on-site experiment shows that frequency responses obtained through the two methods are coincident in the common frequency band, while differences exist between the poles/zeros obtained by transfer function and peaks/troughs in the frequency response curve obtained by FRA. The presented study of this new method verifies its feasibility, demonstrates that it has some advantages over FRA and lays the foundation for further practical applications.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2016年第20期5678-5687,5745,共10页
Proceedings of the CSEE
关键词
绕组变形
M序列
频率响应分析
传递函数
winding deformation
M-Sequences
frequency response analysis （FRA）
transfer function
