高速铁路牵引网电弧故障继电保护原理研究

It is very important for the operation safety of traction power system and even high-speed railway that a protective relay can isolate faulted equipment rapidly and reliably. Several mis-operation cases have been confirmed when an arc fault occurred on traction power network of high-speed railway. In view of the situation that this kind of fault may occur again, arc fault and its relay protection will be studied for the first time from the aspect of traction power network of high-speed railway in this project. The dynamic characteristic of fault arc will be studied. Then the dynamic model of fault arc will be established, based on which an integrated platform will be constructed to simulate traction power system, Multiple Units and fault arc. The arc fault characteristic and its transmission characteristic along the traction power network will be studied, and then the recognition features including waveform, harmonics, instantaneous power rate and moving trajectory will be analyzed. The existing protection elements of traction power network will be evaluated when arc fault occurs. With the algorithm to recognize arc fault features, novel relay protection criteria will be presented based on single-terminal information and multi-terminal information of feeding section. Finally, a new complete protection scheme will formed for the traction power network of high-speed railway. The study achievements of this project will significantly enhance the valid action rate of protective relay for high-speed railway traction power network, and will also produce remarkable economic value and social value.

继电保护快速可靠切除故障设备对于牵引供电系统乃至高速铁路的运行安全十分重要。针对现场运行中已出现的牵引网发生电弧故障但保护拒动的情况，本项目首次以高速铁路牵引网为背景研究电弧故障及其继电保护问题，研究牵引网环境下故障电弧的动态特性；建立牵引网故障电弧的动态模型，构建牵引供电系统－动车组－故障电弧综合仿真平台；研究牵引网电弧故障特性及其沿线传输特性，从波形、谐波、瞬时功率上升率、位移轨迹等方面出发研究电弧故障的识别特征；全面分析既有继电保护元件在电弧故障时的动作行为；研究电弧故障识别特征的提取算法，提出基于单端信息和供电臂多端信息的电弧故障保护原理，构建高速铁路牵引网完整保护方案。本项目的研究成果将从根本上提高高速铁路牵引网继电保护动作的正确率，能够产生显著的经济价值和社会效益。

由于列车带电闯分相、越区隔离开关误合、分相绝缘距离设置不合理等原因，高速铁路牵引网不同相之间会发生异相电弧短路故障，并可能进一步发展为接触网烧损等事故，造成巨大的损失。特别是在我国高速铁路规模大、里程长、密度高的背景下，电分相数量多、动车组速度快，导致异相电弧短路故障增加。随着高速铁路的进一步建设和发展，异相电弧短路故障带来的危害不容忽视。本课题深入研究了高速铁路牵引网电弧及其相关的继电保护问题，对高速铁路的安全可靠运行具有重要意义。.主要内容包括：.（1）在对牵引网电流分布推导的基础上，根据电分相电弧所处的磁场、气流场、温度场、重力场等多物理场分析，依据链式电弧模型构建三维坐标系下速度约束方程，进而求解了电弧的运动轨迹，揭示了起弧初相角和起弧位置对电弧发展演变趋势的影响。.（2）基于电弧理论研究牵引网故障电弧的能量逸散特性，建立电弧耗散功率与电弧运动速度的表征公式，构建拓展Habedank电弧自定义元件，建立牵引供电系统-动车组-故障电弧综合仿真平台。.（3）在推导AT牵引网和牵引变压器等值电路的基础上，分析过渡电阻、变压器参数等对端口阻抗特性及异相电弧短路故障特性的影响。从阻抗轨迹、波形特征、谐波含量、瞬时功率上升率、位移轨迹等方面确立电弧故障的故障特征。.（4）基于Hilbert变换的单相瞬时无功功率理论，提出一种直流功率增量保护原理，并提出了一种以供电臂为单元的网络化馈线保护方案。通过在各所亭配置距离保护，并用联跳信号和闭锁信号将同一供电臂的保护构成一个整体，兼顾保护的选择性和速动性。.（5）利用图论中邻接矩阵分析网络拓扑结构的优势，对高速铁路全并联AT牵引网的拓扑进行了详细地分析，建立了牵引供电系统的开关状态矩阵以此反映牵引网的运行方式，提出基于故障状态矩阵的故障测距思想，消除运行方式对故障测距的影响。