【作者】 李茂亮；

【导师】 王牣；

【作者基本信息】 西南交通大学 ， 电力系统及其自动化， 2012， 硕士

【摘要】 牵引变电所既有保护配置是“一对一”的独立配置,虽然其可靠性较高,但是也存在着硬件配置冗余、二次接线复杂、投资成本大、信息不能实时共享、运行与维护成本高以及缺乏整体协调与功能优化的不足。随着智能变电所技术的日益完善,高速以太网通信技术的发展,计算机软硬件性能的不断提升以及IEC61850标准的颁布实施,集中式保护开始得到了国内外大批学者的关注。集中式保护简化了牵引变电所二次接线、实现了全所数据的实时共享、避免了硬件重复配置、减少了安装保护装置及设备所需的空间。因此,具有明显优势的集中式保护将是未来牵引变电所微机保护的发展方向之一。本文首先分析了智能变电所、IEC61850标准以及通信网络技术对集中式保护的影响,然后将牵引变电所既有保护配置与集中式保护进行对比,阐述了集中式保护的原理及优越性。同时,分析了实现集中式保护功能的一些技术难点,例如对报文传输时延进行了分析,采用了基于标签的关键报文优先传输方法,保证了关键报文传输的实时性和可靠性。基于现有牵引变电所通信网络的星形、环型和总线型网络拓扑结构,提出了混合式双冗余星形组网方案,并对该组网方案的设计思路、优势及可靠性进行了详细说明。通过相关数据计算,对集中式保护硬件设备进行选型,主要包括电子式电压(电流)互感器、合并单元、光纤以太网、交换机以及集中式保护装置的处理器(CPU)等。基于集中式保护的原理及硬件基础,划分了集中式保护的软件任务,包括采样处理任务、保护任务、通信任务。在保护任务中,给出了牵引变电所5个保护的程序流程图。基于Windows操作系统多线程多任务并行运行的特点,对集中式保护软件进行了开发,保护算法选用的是傅立叶算法,同时给出了采样数据异常的处理方法,使用WinPcap对IEC61850-9-2报文进行捕包,采样值数据经傅立叶算法计算后,传送到集中式保护装置中,经保护程序包进行逻辑判断,给出闭锁、告警或跳闸等出口动作指令。构建了一个软件测试平台,在实验室内通过合并单元与智能操作箱向保护软件发送数据,对所编写的软件进行测试验证,测试结果表明捕包程序能够正确捕获报文、保护软件正常运行与故障测试时均能给出正确逻辑判定结果。从硬件可靠性与软件可靠性两方面对集中式保护系统进行可靠性计算与评估。分析计算结果,同时给出提升集中式保护系统可靠性的一些策略。更多还原

【Abstract】 The protective configuration of Traction substation is "one for one" independent configuration of high reliability. But it has some disadvantages including hardware configuration redundancy, complicated secondary wiring, large investment cost, lack of real time information sharing, high cost for operation and maintenance and inadequate overall coordination and the optimization of function. Centralized protection has begun to attract the attention of Chinese scholars as improvements are made in intelligent substation technology, High-speed Ethernet communications technology, the performance of computer hardware and the adoption of IEC61850standard. Centralized protection has simplified Traction substation Secondary wiring, realized real time data sharing, avoided repeated configuration of hardware and reduced the space needed for the installation of protection devices and equipments. In consideration of its advantages, Centralized protection will be the main trend for the development of Microcomputer protection in Traction substation.First the impact of intelligent substation, IEC61850standard and telecommunication network technology to Centralized protection is analyzed, and then made a comparison between the protective configuration of Traction substation and Centralized protection and construed the superiority of Centralized protection in theory and application. Moreover, the author has conducted research on the technical difficulties of centralized protection, like message transmission delay, and then adopted label-mark key message priority transmission method to ensure real time and reliable transmission of key information. Based on the existing network topology shaped in stars-type, rings-type and Bus-type, the author has proposed the Hybrid dual redundant stars-type network scheme, and made detailed explanation on its design, advantages and reliability. Through computation, the author can select the model for the hardware of centralized protection, including electronic voltage (current) transformer、merging unit、Optical Ethernet exchange board, and the CPU of centralized protection device.In view of its theoretical basis and hardware performance, the software tasks of centralized protection such as sample processing, protection and communication are well formulated. In the task of protection, five programming flowcharts are given. Since Windows operation system is featured in parallel running of multi-thread and multi-tasks, the author has developed the software of centralized protection software by adopting in fourier algorithm, and presented ways to deal with unusual sample data. The IEC61850-9-2message is capture packets by WinPcap, computed in fourier algorithm, and then delivered to the protective devices of centralized protection device. The protective package will make logical judgements and send orders like atresia、alarm or tripping operation. A platform for software test is builted which can send data through merging unit and the intelligent operation box and test and verify the software. The result shows that capture packets procedures can capture message correctly and make correct logical judgement when protection software is normally operating or is having a fault testing.From hardware reliability and software reliability to calculation and assess the centralized protection system reliability. At the same time, analysis the calculation result, and some measures to improve the centralized protection system reliability are given.更多还原