采用混沌振子和新相态判别法的局部放电检测

Partial discharge detection using chaotic oscillator and novel phase state identification method

为了降低信号检测的信噪比,利用新型混沌振子作为检测工具,采用Lyapunov指数法分析动力学特性,通过提升临界混沌阈值精度减少在覆盖初始相位差方面混沌振子的使用数量。利用系统周期特点,提出新相态判别法并设计仿真电路,实现相态的自动识别并记录间歇混沌状态周期,最后对指数衰减振荡型局部放电信号进行检测仿真。仿真结果表明,新型混沌振子动力学特性丰富,抗噪性能优越,能够实现更低的信噪比检测,新相态判别法不受过渡过程的影响,具有普适性和电路可实现性,二者结合可以检测超高频毫伏级的变压器局部放电信号。

In order to reduce the SNR of signal detection,a novel chaotic attractor was used as a detection tool.Lyapunov exponent method was used to analyze the dynamic characteristics.The number of chaotic oscillators used in covering the initial phase difference was reduced by increasing the accuracy of the critical chaotic state threshold.A novel phase state identification method was proposed and designed in circuit simulation.It can realize the automatically identify phase states by using the period characteristics of the system.The period of intermittent chaotic state was recorded.Finally,the detection and simulation of the partial discharge signal with exponential attenuation oscillation were carried out.The simulation results show that the novel chaotic attractor has rich dynamic characteristics and superior anti-noise performance.It can achieve lower SNR detection.Unaffected by the transition process,the novel phase state identification method is applicable to any chaotic oscillator and has the feasibility of circuit implementation.A combination of the novel attractor and new method can realize detection of ultra-high frequency millivolt-level partial discharge signals of transformer.