摘要
为了便于接地网故障诊断,建立了接地网的分块模型,定义了块及其原形、不确定支路组及其原形、块的投影和节点分区等概念;在此基础上,提出了一种基于分块模型的分块故障诊断方法,根据接地网中拟需诊断的支路分布确定接地网中参与诊断的块及其投影和分区;基于面向各个节点分区的测试数据,采用线性最小二乘法求解出各个块内的本征支路电阻,确定各块中明晰支路电阻,并采用二分法求出不确定支路电阻的取值范围。提出的方法能够将大规模的接地网拆分成若干个小规模子网络进行求解,不仅可以提高计算效率,还可减少各个不同块间测试数据的交叉干扰的影响,且避免了已往方法求解本征支路电阻的非线性迭代过程。对陕西渭南330 kV变电站内的38条支路的实验接地网进行实验验证的结果表明,所建议的方法是可行的;在对接地网进行局部故障诊断时,只需对相关部分进行测试即可,能够减少测试工作量,有效提高故障诊断效率。
For fault diagnosis,concepts of blocks and their prototypes,uncertain-branch groups and their prototypes,projection of blocks and part of touchable nodes are defined,and a new approach of diagnosing the fault of grounding grids by blocks is put forward.According to the desired fault diagnosis area,the blocks together with their projections and the parts of touchable nodes,which participate in the diagnosis,are determined.According to tested data of the corresponding parts,the resistances of intrinsic branches in a block can be determined by a linear least square method,by which the resistances of clear branches in the block can be worked out.The ranges of resistances of uncertain-branches in the block are also evaluated by a dichotomy algorithm.With the proposed approach,a grounding grid can be divided into several small-scale sub-grids.As a result,the efficiency is improved and the cross-interferences are reduced.An experimental grounding grid with thirty-eighty branches is used as an example.The results of fault diagnosis show that the proposed approaches are feasible,and only a few tests are needed to meet the requirements of diagnosing a certain part of the grounding grid.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2011年第5期1194-1202,共9页
High Voltage Engineering
基金
新世纪优秀人才支持计划(NCET050875)~~
关键词
接地网
故障诊断
分块诊断
线性最小二乘法
区测试
二分法
grounding grids
corrosion diagnosis
diagnosis within a block
linear least square method
test within a part
dichotomy algorithm
