摘要
电气设备油中局部放电超声阵列定位是将阵列信号处理技术应用于局放超声检测中的一种新方法,其实质是通过相应的算法得到信号的方位信息,继而对局放源进行定位。研究表明,当超声传感器接收到直达信号时,可对局放源进行准确定位;当接收到混叠(多路径)信号时,会导致定位成功率和定位精度下降,甚至产生虚假定位。因此,有效识别超声直达波与混叠波信号是局放定位成功的关键。该文选取峰值因数、分形盒维数和李雅普指数作为局放超声直达波信号的特征参量;分别基于各特征量进行超声直达波识别的仿真研究,结果表明超声信号的混叠程度会对识别结果造成很大影响,利用BP人工神经网络,提出一种基于多特征量的电气设备油中局放超声直达波识别方法,仿真结果显示其识别成功率接近100%;最后在设定环境下进行油中局放超声直达波识别的实验研究,结果表明,采用单个特征量识别直达波和混叠波的成功率约为90%,基于多特征量的识别成功率为95%,验证了所提方法的有效性。
The ultrasonic array position of the partial discharge （PD） in oil is a new method to PD detection. Research suggested that, when the sensor received a direct signal, the PD could be accurately positioned; when the sensor received an aliasing signal, the success rates were reduced. Therefore, the effective identification of the ultrasonic direct and aliasing waves is key to PD positioning. First, peak factor, fractal box dimension and Lyapunov exponent are extracted as the characteristic parameters of the partial discharge （PD） ultrasonic direct wave in this paper; Second, simulation was done to identify the ultrasonic direct wave and superimposed wave using these characteristic parameters respectively, and the results show that the aliasing degree of ultrasonic signals has a significant impact on identification result; so a method based on BP artificial neural network is used to identify the direct wave which takes all characteristic quantities into consideration, the simulation results show the success rates are closed to 100%; Finally, the direct wave identification experiments are made in set environment, it indicates that the success rate of identification using single characteristic parameter is about 90% while the success rate is 95% using multi-characteristic parameters, which demonstrates the validity of this method.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2014年第3期478-485,共8页
Proceedings of the CSEE
基金
国家自然科学基金项目(51307060)
国家863高技术基金项目(2011AA05A121)~~
关键词
局部放电
超声直达波
混叠波
分形
混沌
partial discharge （PD）
ultrasonic direct wave
superimposed wave
fractal
chaos
