基于直角坐标系改进的杜瓦尔三角形充油电力设备故障诊断方法

Fault Diagnosis of Oil-Filled Power Equipment Based on an Improved Duval Triangle in Rectangular Coordinate System

中文关键词:充油电力设备  油中溶解气体分析  杜瓦尔三角形

keywords:oil-filled power equipment  dissolved gas analysis in oil  Duval triangle

中文摘要:溶解气体分析是充油电力设备内部故障诊断的核心技术。针对IEC 60599推荐的杜瓦尔三角形法存在坐标系复杂、直观性不足、变量冗余和计算复杂等问题，提出一种基于直角坐标系的改进杜瓦尔三角形法。该方法根据故障区域边界的几何特征，从3种气体百分含量中选取2个作为独立变量，构建等腰直角三角形诊断空间，在完全保留IEC 60599故障判据与诊断逻辑的基础上，将原有复杂的斜向边界转化为以水平线和垂直线为主的边界，且低能量故障区域位于坐标原点附近，符合工程使用习惯。诊断过程仅需基本比较运算，无需复杂坐标变换或几何计算，显著提升了人工判读的便捷性与可靠性，并且更加适配嵌入式与智能诊断系统。结果表明，该方法与传统杜瓦尔三角形法的诊断结果完全一致。

Abstract:Dissolved gas analysis is a core technology for diagnosing internal faults in oil-filled power equipment.However，the Duval Triangle method recommended by IEC 60599 has drawbacks such as a complex coordinate system，insufficient intuitiveness，redundant variables，and complicated calculations.To address these issues，this paper proposes an improved Duval Triangle method based on a rectangular coordinate system.According to the geometric characteristics of fault zone boundaries，the method selects two of the three gas percentage contents as independent variables to construct a diagnostic space in the form of an isosceles right triangle.While fully retaining the fault criteria and diagnostic logic specified in IEC 60599，it converts the original complex oblique boundaries into boundaries dominated by horizontal and vertical lines，with low-energy fault zones located near the coordinate origin，which is consistent with engineering practice.The diagnostic process only requires basic comparison operations without the need for complex coordinate transformations or geometric calculations，which significantly improves the convenience and reliability of manual interpretation and is more suitable for implementation in embedded and intelligent diagnostic systems.The diagnostic results of this method are completely consistent with those of the traditional Duval Triangle method.