电流互感器暂态特性试验用标准信号的参数估计

发布时间：2018-11-10 16:33

【摘要】：电流互感器的暂态特性是影响继保装置正确动作、攸关系统安全稳定的关键因素之一,对入网的电流互感器开展暂态特性试验或检测具有重要意义。为准确掌握试验用标准信号的信息,提出了相应的参数估计方法。在噪声允许的范围内,求标准信号的正极大值。结合暂态发生的时间信息,截取出暂态时段内的各个正极大值,再利用对数变换将其转换为直线函数,使用最小二乘法拟合得到直线的截距与斜率,分别对应暂态电流的幅值及时间常数。仿真结果表明:当标准信号的采样频率为6.4 kHz并伴有20 dB高斯白噪声时,所提方法能精确估计出暂态发生时刻,对暂态电流时间常数的估计精度高于暂态电流幅值,暂态电流时间常数的估计范围为80?210 ms。所得结论为开展电流互感器的暂态特性试验提供了参考依据。
[Abstract]:The transient characteristic of current transformer is one of the key factors that affect the correct operation of the relay device and the safety and stability of the system. It is of great significance to test or detect the transient characteristics of the current transformer entering the network. In order to accurately grasp the information of standard signals used in experiments, a corresponding parameter estimation method is proposed. The positive maximum of the standard signal is obtained within the range of noise. Combined with the time information of transient occurrence, the positive maximum in the transient period is obtained, and then the logarithmic transformation is used to transform it into a straight line function, and the intercept and slope of the line are obtained by using the least square method. The amplitude and time constant of transient current are respectively corresponding. The simulation results show that when the sampling frequency of the standard signal is 6.4 kHz with 20 dB Gao Si white noise, the proposed method can accurately estimate the transient occurrence time, and the estimation accuracy of the transient current time constant is higher than the transient current amplitude. The estimated range of transient current time constant is 80 ~ 210 ms. The conclusion provides a reference for the transient characteristic test of current transformer.
【作者单位】：中国电力科学研究院;国网湖北省电力公司电力科学研究院;
【基金】：国家电网公司科技项目(《提高特高压互感器可靠性技术研究》)(合同编号EPRIGYKJ[2012]4939号) Science and Technology Project of the State Grid Corporation of China(“Research to Improve the Reliability of UHV Instrument Transformer”)(No.EPRIGYKJ[2012]4939)
【分类号】：TM452

【相似文献】