基于分层匹配和最长公共子序列的SCD文件比较算法

IEC61850通信已经在电力系统中广泛使用，其中变电站通信系统使用SCD文件进行描述.SCD文件是XML格式的层次化结构，不适合直接用文本按行对比来分析差异.同时由于SCD文件层次结构多，使用纯结构化的比较方法，会导致比较结果冗长，执行效率低.本文基于SCD文件的特征，提出了分层匹配的半结构化半文本比较思路.先按照智能电子设备、连接接入点、逻辑设备等层次结构，提取关键属性名，进行对齐匹配.之后在逻辑设备范围内，针对逻辑节点的内容，采用最长公共子序列的匹配算法对比局部文本内容，该算法可去除仅调整顺序不影响实体内容的无效差异，比较速度快，比较结果准确直观.

SCD File Comparison Algorithm Based on Hierarchy Match and Longest Common Subsequence

IEC61850 communication has been widely used in electric power system,and SCD file is adopted to describe the Substation Communication System.Hierarchical structure of the SCD file is an XML format,making it not suitable for direct text comparison methods.Meanwhile,the levels of SCD file hierarchy are too many for pure structured comparison methods,which make them lack of time and space efficiency.Based on characteristics of the SCD file,this paper proposes a hierarchical combined approach of structured match and text comparison.Firstly,we abstract critical attribute names with hierarchy information of IED/AccessPoint/LDevice and compare the hierarchy correspondently with structured comparison method which is based on critical attributes.Secondly,we compare the content of LNode with what is based on longest common subsequence algorithm.This combined method could remove invalid differences arising by sequence modification,and could complete the comparison much faster with more accurate and straight forward comparison results.