【作者】 丁家峰；

【导师】 罗安； 曹建；

【作者基本信息】 中南大学 ， 控制理论与控制工程， 2012， 博士

【摘要】 油中溶解气体是表征运行充油型电气设备早期潜伏性故障的重要特征量之一,油中溶解气体在线监测技术在充油型电气设备运行状态的在线评估及剩余寿命的预测领域具有良好的应用前景。固体氧化物燃料电池(solid oxide fuel cell,简称SOFC)具有灵敏度高、检测气体种类丰富及使用寿命长等优点,其在变压器油中溶解气体检测领域具有巨大的应用潜力。论文从SOFC的多组份气体检测理论分析、SOFC气体传感器的研制、SOFC变压器油中溶解气体在线监测系统设计及应用四个方面着手,系统地研究了油中溶解气体的SOFC检测原理及技术。主要研究内容如下：1.提出了适用于多组份气体的SOFC检测理论。通过热力学和动力学理论的分析证明了SOFC对H2, CO, CH4, C2H6, C2H4和C2H2等故障气体具有线性响应特性,但对N2无响应。设计了结合色谱分离的SOFC多组份气体实验方案,实验结果验证了理论分析的正确性。2.构建了SOFC气体检测器的应用模型。综合考虑检测过程中的各种损耗因素,通过改进SOFC发电模型,建立了SOFC气体检测的应用模型。详细分析了模型中的热力学和动力学参数,发现恒定的温度是热力学稳定的重要条件、动力学极化损耗随待测气体浓度的变化而变化,而欧姆损耗仅取决于材料本身。3.研制了管状SOFC气体传感器。通过气体燃烧损耗的流体力学分析,优化了通道结构设计和流速控制。设计了基于PID控制算法的双路温度控制系统,该设计既能保证管状SOFC传感器温度稳定在700±1℃,又使色谱柱温度稳定在70±0.1℃。实验结果表明：SOFC气体传感器较其它传感器精度高、寿命长、需要的载气种类少。4.研制了基于SOFC的变压器油中溶解气体在线监测系统。设计了基于高分子膜油气分离和多柱联用气体分离的预处理单元,使脱气的最高效率可以达到每小时一次；设计了基于ARM加CPLD的主控制单元,不仅保证了测量精度、通讯的可靠性,而且实现了开关量的实时控制；设计了当地控制台、当地手动检测和计算机自动检测流程为一体的综合嵌入式软件系统,为系统的运行提供了高可靠的、人性化的及便捷的多功能操作模式；提出了一种结合平滑滤波和增加斜率检索法的自动寻峰算法,保证了数据处理的正确性。最后,模拟实验验证了系统对设备故障诊断的正确性。5.将基于SOFC的变压器油中溶解气体在线监测系统应用于某500kV三相一体变压器。通过采用高性能连接材料和精密齿轮泵,保证了油路的可靠性,避免了油流带电现象的发生；通过机械和电气的优化设计保证了设备长期运行的可靠性以及数据融合的灵活性；挂网运行数据结果显示：该变压器油中溶解气体在线监测系统运行稳定,测量数据精度高,为电气设备的安全运行提供了强有力的保障。更多还原

【Abstract】 Gases dissolved in transformer oil are important characteristic values which reflect the types of incipient faults of oil-immersed power apparatus, and on-line monitoring of dissolved gases has fine application prospects in the application to on-line evaluation of the running state of oil-immersed power apparatus and on-line forecast of their residual lives. As a new type of fuel cell, solid oxide fuel cell (SOFC) has some advantages including high sensitivity, response to kinds of gases, and long service life, which make it has great application potential in the field of dissolved gases evaluation. This dissertation investigates systematically the detection mechanism and technology of gases dissolved in transformer oil based on SOFC. The main researches as follows:1. Detection theory of SOFC about multicomponent gases has been put forward. Thermodynamics and kinetics analyses show that SOFC has linear response to some fault gases, such as H2, CO, CH4, C2H6, C2H4and C2H2, but not to N2. Combined with chromatographic separation, SOFC multicomponent gases experimental scheme has been designed, from which the correctness of the theoretical analyses is test.2. Application model of SOFC gas detector has been built. This model is an improved one of SOFC power model. Through the analyses of thermodynamics and kinetics parameters of it, constant temperature is found to be very important for thermodynamic stability. Results of the analyses still indicate that polarization loss is a parameter which varies with the change of gas concentration, and ohmic loss is affected only by the materials and construction.3. A tubular SOFC gas sensor has been developed. Its channel structure and flow control have been optimized through the analysis of gas combustion loss and hydrodynamic. A dual temperature control system bas been designed, which can ensure the temperature of tubular SOFC sensor and chromatographic column to be stable at700±1℃and70±0.1℃.The experiment results show that the SOFC gas sensor has advantages of high precision, long service life and less carrier gas kinds need.4. An on-line monitoring system for gases dissolved in transformer oil based on SOFC has been developed. In this system, the pretreatment unit based on polymer membrane gas\oil separation and multicolumn gas separation makes the peak degassing efficiency reach once per hour; the main control unit based on ARM and CPLD will ensure the measuring accuracy, communication reliability and realtime control of the system as well. And the integrated embedded software system, which includes local console,local manual detection and computer automatic detection, offers high reliability, humanization and convenient multifunctional operate mode for the system. At last, an automatic peak-seeking algorithm combined with median filtering and increasing slope retrieval method has been put forth, which ensures the correctness of data processing.At last, fault simulation tests verify the accuracy of this system on fault diagnosis.5. The designed on-line monitoring system for gases dissolved in transformer oil based on SOFC has been applied in a500kV integrated three-phase transformer. By adopting of high performance connections materials, precision gear pump and the optimized design of mechanic and electric, the oil electrification phenomenon can be avoided and the long running reliability of equipment, the flexibility of data fusion can be guaranteed. Running results show that this system runs stably, measures accurately. So it can ensure the safe running of the transformer.更多还原