Spatial division multiplexing enabled elastic optical networks(SDM-EONs) are the potential implementation form of future optical transport networks, because it can curve the physical limitation of achievable transmiss...Spatial division multiplexing enabled elastic optical networks(SDM-EONs) are the potential implementation form of future optical transport networks, because it can curve the physical limitation of achievable transmission capacity in single-mode fiber and single-core fiber. However, spectrum fragmentation issue becomes more serious in SDM-EONs compared with simple elastic optical networks(EONs) with single mode fiber or single core fiber. In this paper, multicore virtual concatenation(MCVC) scheme is first proposed considering inter-core crosstalk to solve the spectrum fragmentation issue in SDM-EONs. Simulation results show that the proposed MCVC scheme can achieve better performance compared with the baseline scheme, i.e., single-core virtual concatenation(SCVC) scheme, in terms of blocking probability and spectrum utilization.展开更多
【目的】干式空心电抗器(dry-type air-core reactor,DAR)在运行中易发生匝间短路故障,该类故障具有隐蔽性强、难以实时察觉的特点,对电网的安全稳定运行构成严重威胁。工程中广泛采用的基于磁感应强度幅值的检测方法存在局限性,其对内...【目的】干式空心电抗器(dry-type air-core reactor,DAR)在运行中易发生匝间短路故障,该类故障具有隐蔽性强、难以实时察觉的特点,对电网的安全稳定运行构成严重威胁。工程中广泛采用的基于磁感应强度幅值的检测方法存在局限性,其对内层绕组匝间短路的响应不灵敏,且在多台DAR并列运行时,邻近设备产生的磁场干扰会显著影响检测准确性。为提升故障识别能力并实现早期预警,本文提出一种基于磁场方向角(magnetic field direction angle,MFDA)的DAR匝间短路检测方法。【方法】基于有限元仿真技术,模拟了单相DAR在正常运行及不同位置发生匝间短路时的周围磁场分布;通过在DAR周围设置多个监测点,采集磁感应强度数据,分析了故障发生前后磁感应强度的变化规律;依据磁场叠加原理,计算并分析了三相DAR中故障相附近各监测点MFDA的时序变化规律;对比单台与多台DAR并列运行的MFDA数据,量化评估了邻近正常运行DAR对故障检测的干扰程度,并优化了监测点的布局。【结果】仿真结果表明,单相DAR发生匝间短路后,其周围的磁感应强度幅值和方向均发生了显著变化;与基于幅值的检测方法相比,MFDA对匝间短路表现出更高的响应灵敏度,能够准确捕捉故障所引起的电磁特性变化;通过分析故障发生前后各监测点MFDA的时序变化并设定故障判定阈值,可实现单相DAR匝间短路的诊断;对于三相DAR并列运行场景,在故障相附近、正常相对称中垂线上设置监测点,可有效减少邻近DAR的磁场干扰,结合MFDA时序特征与故障判定阈值,仍能实现短路故障诊断。【结论】提出的基于MFDA的检测方法能够有效弥补磁感应强度幅值检测法在灵敏度和抗干扰能力方面的不足,为DAR运行状态的实时监测与故障预警提供了一种可靠的技术手段。该方法基于仿真研究,展现出良好的工程应用潜力,对提升电网设备运维水平、保障电力系统安全稳定运行具有实际应用价值。展开更多
基金supported in part by NSFC project (61571058, 61601052)
文摘Spatial division multiplexing enabled elastic optical networks(SDM-EONs) are the potential implementation form of future optical transport networks, because it can curve the physical limitation of achievable transmission capacity in single-mode fiber and single-core fiber. However, spectrum fragmentation issue becomes more serious in SDM-EONs compared with simple elastic optical networks(EONs) with single mode fiber or single core fiber. In this paper, multicore virtual concatenation(MCVC) scheme is first proposed considering inter-core crosstalk to solve the spectrum fragmentation issue in SDM-EONs. Simulation results show that the proposed MCVC scheme can achieve better performance compared with the baseline scheme, i.e., single-core virtual concatenation(SCVC) scheme, in terms of blocking probability and spectrum utilization.
文摘【目的】干式空心电抗器(dry-type air-core reactor,DAR)在运行中易发生匝间短路故障,该类故障具有隐蔽性强、难以实时察觉的特点,对电网的安全稳定运行构成严重威胁。工程中广泛采用的基于磁感应强度幅值的检测方法存在局限性,其对内层绕组匝间短路的响应不灵敏,且在多台DAR并列运行时,邻近设备产生的磁场干扰会显著影响检测准确性。为提升故障识别能力并实现早期预警,本文提出一种基于磁场方向角(magnetic field direction angle,MFDA)的DAR匝间短路检测方法。【方法】基于有限元仿真技术,模拟了单相DAR在正常运行及不同位置发生匝间短路时的周围磁场分布;通过在DAR周围设置多个监测点,采集磁感应强度数据,分析了故障发生前后磁感应强度的变化规律;依据磁场叠加原理,计算并分析了三相DAR中故障相附近各监测点MFDA的时序变化规律;对比单台与多台DAR并列运行的MFDA数据,量化评估了邻近正常运行DAR对故障检测的干扰程度,并优化了监测点的布局。【结果】仿真结果表明,单相DAR发生匝间短路后,其周围的磁感应强度幅值和方向均发生了显著变化;与基于幅值的检测方法相比,MFDA对匝间短路表现出更高的响应灵敏度,能够准确捕捉故障所引起的电磁特性变化;通过分析故障发生前后各监测点MFDA的时序变化并设定故障判定阈值,可实现单相DAR匝间短路的诊断;对于三相DAR并列运行场景,在故障相附近、正常相对称中垂线上设置监测点,可有效减少邻近DAR的磁场干扰,结合MFDA时序特征与故障判定阈值,仍能实现短路故障诊断。【结论】提出的基于MFDA的检测方法能够有效弥补磁感应强度幅值检测法在灵敏度和抗干扰能力方面的不足,为DAR运行状态的实时监测与故障预警提供了一种可靠的技术手段。该方法基于仿真研究,展现出良好的工程应用潜力,对提升电网设备运维水平、保障电力系统安全稳定运行具有实际应用价值。
