基于分布式光纤测温技术的超导电缆 局部失超检测和保护方法

现有失超保护方法大多只能检测出整体失超故障,而不能有效反映局部失超故障。为此,根据超导电缆发生局部失超后,导体层沿线温度波形出现波峰特征,提出了一种基于分布式光纤测温技术的超导电缆局部失超检测和保护方法。该方法利用光纤测温系统测量超导电缆导体层沿线温度,使用高斯滤波进行测温数据的消噪处理,通过多分辨形态学梯度(MMG)辨识沿线温度波形中波峰的上下边沿,进而计算确定局部失超发热区域。最后根据发热区域的大小和温升情况,进行告警和跳闸。仿真结果表明,所提出的方法具有良好的抗噪性能,可准确检测和判断失超发热区域和失超故障严重程度,有效保证超导电缆运行安全。

A local quench detection and protection method for a superconducting cable based on distributed optical fiber temperature measurement technology

Most existing quench protection methods can only detect the overall quench fault, and cannot effectively reflect the local quench fault. Therefore, given the peak characteristics of the temperature waveform along the conductor layer after the local quench of the superconducting cable, a local quench detection and protection method for a superconducting cable based on distributed optical fiber temperature measurement technology is proposed. The method uses a fiber optic system to measure the temperature along the conductor layer of the superconducting cable, a Gaussian filter to filter out the noise in temperature data, and identifies the upper and lower edges of the wave peaks in the temperature waveform by a multi-resolution Morphological Gradient (MMG). Then the local quench heat-generating zones are calculated and determined. Finally, alarm and tripping are carried out according to the size and temperature rise of the quench heat-generating zones. Simulation results show that the proposed method has good anti-noise performance, can accurately detect and judge the quench heat-generating zones and quench fault severity, and effectively ensure the operational safety of the superconducting cable. This work is supported by National Natural Science Foundation of China (No. 51677080) and Science and Technology Project of Shenzhen Power Supply Bureau Co., Ltd. (No. 090000KK52170171).