摘要
目前电网广泛使用的微机母线保护装置都是通过引入隔离刀闸辅助接点来实现母线保护的自适应运行,该方法虽然直接有效但仍存在多种缺陷。文章提出了一种母线保护运行方式自适应判别的新方案,首先利用电流瞬时值来检出有电流支路,再利用递归算法对检出的支路进行排列组合,直至算出两段平衡的小差(即与该段母线相连的各支路电流构成的差动回路,其中包括与该段母线相关联的母联开关和分段开关支路)为止,然后对两段小差不断进行平衡校验并对各种情况分别进行判别。该方案对微机平台的运算能力及保护装置电流测量精度的要求很高,通过该方案可最大限度地降低母线保护装置对刀闸辅助接点的依赖,从而提高母线保护装置运行的可靠性。
At present to realize the adaptive operation of busbar protection, the auxiliary contacts of disconnecting switches are led into the widely used microcomputer based busbar protections as the main criteria. This method is effective but there are still some defects in it. A new scheme to adaptively judge the operation mode of busbar protection is proposed. In this method firstly using the instantaneous current values to detect the current-carrying branches, then the permutation and combination of the detected current-carrying branches are carried out by recursive algorithm, until two balanced differential networks which are constituted by each current-carrying branches connected to the busbar and contain the bus-tie circuit breakers incident with that sections of busbar and the branches containing the disconnected switches are obtained, finally the balance check of the two balanced differential networks are unceasingly carried out and the different situations are judged respectively. The proposed scheme requires high operational capability of microcomputer and high current measuring accuracy of the protection. With this scheme the dependence of busbar protection on auxiliary contacts' states can be reduced utter mostly, therefore the operation reliability of busbar protection is improved.
出处
《电网技术》
EI
CSCD
北大核心
2005年第7期60-64,共5页
Power System Technology
