地下交叉互联高压电缆分布式护层电流传感系统的时滞控制方法  

Time Delay Control Method for Distributed Sheath Current Sensing System of Underground Cross-Bonding High Voltage Cable

作　　者：周莎莎 王航 杨斌 夏湛然 周承科 Zhou Shasha;Wang Hang;Yang Bin;Xia Zhanran;Zhou Chengke(Hubei Engineering Research Center for Safety Monitoring of New Energy and Power Grid Equipment Hubei University of Technology,Wuhan 430068 China;Wuhan Power Supply CompanyHubei Power Supply Company State Grid,Wuhan 430024 China;Glasgow Caledonian University,Glasgow UKG40BA)

机构地区：[1]湖北工业大学新能源及电网装备安全监测湖北省工程研究中心,武汉430068 [2]国网湖北省电力公司武汉供电公司,武汉430024 [3]格拉斯哥卡里多尼亚大学,格拉斯哥G40BA

出　　处：《电工技术学报》2024年第4期1234-1244,共11页Transactions of China Electrotechnical Society

基　　金：湖北省电力公司科技项目(SGTYHT/21-JS-223);湖北工业大学科研启动基金项目(HSQD2020020)资助。

摘　　要：交叉互联高压电缆系统中的分布式护层电流检测对于护层接地故障诊断至关重要。为解决地下高压电缆不依赖外部时标的分布式护层电流传感时间同步问题,该文基于交叉互联高压电缆护层间的耦合关系,采用并联Smith预估补偿器提升时滞补偿效率,获取残差最小的时间偏置补偿时滞量,提出多护层电流传感器时滞误差的递归最小二乘跟踪方法,以电容电流短时不变为稳定判据,对实际测量时分布式护层电流传感器之间的时延进行估计和控制。该方法在220 kV高铁牵引变压器一次侧高压电缆分布式护层电流传感系统上进行了试验验证,验证结果表明,该方法收敛至最小残差值点,平均残差为0.30 A,准确时滞量为3.93 s,能实现分布式护层电流传感的时间同步。Underground HV(High Voltage)cable is the backbone of modern urban power systems.In the last decades,the sheath-to-ground fault is becoming one of the main modes contributing to the single-phase grounding fault.Sheath current sensing is widely adopted in field tests to detect the sheath-to-ground fault.However,the synchronization of distributed sheath current sensing based on GPS(Global Position System)or Beidou is unstable because the time transfer tag is usually unavailable in underground cable tunnels.Therefore,a time delay control method based on the Smith predictor compensator and recursive least squares method(RLSM)is proposed using the capacitive current as a reference of the measured sheath current in the same sheath loop.Firstly,the architecture of the distributed sheath current sensing in HV cross-boned cable systems is introduced,and the formulation of the measured sheath current in the same sheath loop with time delay is deduced.Secondly,the electromagnetic coupling relationship between the sheath current and load current is modeled,and the phasor difference of the measured sheath current in the same sheath loop without time delay is formulated as the reference of the RLSM.Thirdly,the parallel Smith predictor is proposed to compensate for the time delay error of the adjacent sheath current detection points in the same sheath loop.Finally,a recursive least square tracking method for the time delay error of the multi-sheath current sensor is proposed to obtain the time delay with the minimum residual.The proposed method is verified by field tests of a 220 kV cross-boned cable supplying the high-speed traction transformer.The results show that the waveform of capacitive current,which is the reference of RLSM,inosculates well with the difference of the measured sheath current in the same sheath loop after using the proposed method.The maximum difference is 0.297 A,and the minimum difference is 0.002 A.Moreover,the reference standard for time delay estimation is the average residual of the three loops,and t

关 键 词：高压电缆 交叉互联 护层电流 在线监测 时滞控制 

分 类 号：TM274[一般工业技术—材料科学与工程]