【作者】 邹杰慧；

【导师】 颜运昌；

【作者基本信息】 湖南大学 ， 机械电子工程， 2004， 硕士

【摘要】 以油中溶解气体为特征量对变压器进行故障诊断是一种使用广泛而十分有效的方法。本文深入分析了以油中溶解气体为特征量诊断变压器内部故障的原理，并对目前使用最广泛的三比值诊断法进行了分析。三比值诊断法虽然具有较高的准确率，但是，当比值恰好在编码区间的边界处时，它就可能发生误判和错判。这是阈值诊断法无法避免的缺陷。 针对这个问题，本文研究了三比值模糊化编码诊断法，发现其虽然模糊了编码的界限，但是实质上仍然存在阈值的问题，并不能够从根本上解决此问题。本文通过研究，提出了一种全新的模糊诊断模型——模糊综合评判诊断法，并结合变压器实际情况，详细阐述了如何通过模糊化编码获得权向量C；如何确定关系矩阵R以及如何选取模糊算子。 本课题是湖南电力试验研究所状态检修中心“变压器状态监测与诊断”项目的子课题，课题的目的是要建立一套专家诊断系统，因此本文对模糊专家系统的原理和实现方法进行了研究。结合实际，对知识库和推理机的设计，数据库结构的设计等进行了深入的研究。最后，根据模糊综合评判诊断模型，本文以Visual C++6.0为开发工具，在Windows2000平台上开发设计出了一套变压器故障诊断模糊专家系统。 最后，本文根据历史数据和实际的故障情况，对本推理模型及专家系统进行了验证。证明了本模型能够发扬三比值法的优点，弥补三比值法的不足，进一步提高诊断的准确率。同时本系统具有界面友好，易于操作和维护，运行快捷、准确等特点。更多还原

【Abstract】 It is a widely used and quit efficient method to use gas dissolved in oil as character to diagnose transformer fault. This article has deeply analyzed the principle of using gas dissolved in oil as character to diagnose transformer fault, and analyzed the three ratio method to diagnose power transformer which is currently widely used. Three-ratio method has high exactness rate, but it may bring about errors or mistakes if the ratio is just at the boundary of the coding-zone. This is the unavoidable fault of valve diagnosis.This article has researched on the Three-ratio method fuzzy coding diagnosis focusing on the problem, finding that although it fuzzy the boundary of coding-zone, it has still the valve problem and can’t solve it perfectly.A new diagnosis model-fuzzy synthesis diagnosis was developed in thisarticle. With the actual condition of transformer, this article has mentioned how to calculate the vector C, to set the relation matrix R, and to select fuzzy calculation factor.This work is a part of "transformer condition monitoring" of condition monitoring center in Hunan Electric Power Test & Research Institute, its goal is to establish a suitable expert diagnosis system. Considering the actual condition, deeply research on the design of knowledge base, consequence-unit, the structure of database and the principle and realization of fuzzy expert diagnosis system has researched.Based on fuzzy synthesis judgement diagnosis model, this article has developed a set of transformers fault diagnosis fuzzy expert system base on the platform of Windows2000 with Visual C++ 6.0 as kit.According to history data and actual faults, this article has tested this model, Proving that this model can develop the advantage of Three-ratio method, make up the shortage of Three-ratio method, increase the exactness rate of diagnosis. At the same time this system has many good characteristics such as the friend interface, easy operation and maintenance, calculating fast and accurate and so on..更多还原