概率转移矩阵(Probabilistic Transfer Matrix,PTM)方法是一种能够在门级比较精确地估计差错对电路可靠性影响的方法,但目前其实现方法只能适用于较小规模的电路.本文引入了电路划分的思想,先把电路分割成一组适宜用原始PTM方法直接计...概率转移矩阵(Probabilistic Transfer Matrix,PTM)方法是一种能够在门级比较精确地估计差错对电路可靠性影响的方法,但目前其实现方法只能适用于较小规模的电路.本文引入了电路划分的思想,先把电路分割成一组适宜用原始PTM方法直接计算其可靠度的模块,然后计算出这些模块的可靠度,再依据串行可靠度模型,将所有模块可靠度合成为整个电路的可靠度.本文用实验的方法通过对74系列电路的分析得到了合适的电路分割参数,即分割宽度,再进一步对ISCAS85基准电路进行了可靠度的计算,结果表明新方法可以适用于更大规模的无冗余组合电路.通过与依据美军标MIL-HDBK-217所算得的可靠度的比较,验证了本文所提出的方法的合理性.展开更多
Aiming at the problemthat the traditional short-circuit current calculationmethod is not applicable to Distributed Generation(DG)accessing the distribution network,the paper proposes a short-circuit current partitioni...Aiming at the problemthat the traditional short-circuit current calculationmethod is not applicable to Distributed Generation(DG)accessing the distribution network,the paper proposes a short-circuit current partitioning calculation method considering the degree of voltage drop at the grid-connected point of DG.Firstly,the output characteristics of DG in the process of low voltage ride through are analyzed,and the equivalent output model of DG in the fault state is obtained.Secondly,by studying the network voltage distribution law after fault in distribution networks under different DG penetration rates,the degree of voltage drop at the grid-connected point of DG is used as a partition index to partition the distribution network.Then,iterative computation is performed within each partition,and data are transferred between partitions through split nodes to realize the fast partition calculation of short-circuit current for high proportion DG access to distribution network,which solves the problems of long iteration time and large calculation error of traditional short-circuit current.Finally,a 62-node real distribution network model containing a high proportion of DG access is constructed onMATLAB/Simulink,and the simulation verifies the effectiveness of the short-circuit current partitioning calculation method proposed in the paper,and its calculation speed is improved by 48.35%compared with the global iteration method.展开更多
The incidence chromatic number of G is the least number of colors such that G has an incidence coloring. It is proved that the incidence chromatic number of Cn^p, the p-th power of the circuit graph, is 2p ＋ 1 if and...The incidence chromatic number of G is the least number of colors such that G has an incidence coloring. It is proved that the incidence chromatic number of Cn^p, the p-th power of the circuit graph, is 2p ＋ 1 if and only if n = k（2p ＋ 1）, for other cases： its incidence chromatic number is at most 2p ＋ [r/k] ＋ 2, where n = k（p ＋ 1） ＋ r, k is a positive integer. This upper bound is tight for some cases.展开更多
In this paper, a sufficient condition to partition a travel into circuits of length at least 3 is provided， In particular, a necessary and sufficient condition to partition a planar travel into such circuits, which c...In this paper, a sufficient condition to partition a travel into circuits of length at least 3 is provided， In particular, a necessary and sufficient condition to partition a planar travel into such circuits, which can he verified in polynomial time, is provided，展开更多
文摘概率转移矩阵(Probabilistic Transfer Matrix,PTM)方法是一种能够在门级比较精确地估计差错对电路可靠性影响的方法,但目前其实现方法只能适用于较小规模的电路.本文引入了电路划分的思想,先把电路分割成一组适宜用原始PTM方法直接计算其可靠度的模块,然后计算出这些模块的可靠度,再依据串行可靠度模型,将所有模块可靠度合成为整个电路的可靠度.本文用实验的方法通过对74系列电路的分析得到了合适的电路分割参数,即分割宽度,再进一步对ISCAS85基准电路进行了可靠度的计算,结果表明新方法可以适用于更大规模的无冗余组合电路.通过与依据美军标MIL-HDBK-217所算得的可靠度的比较,验证了本文所提出的方法的合理性.
基金funded by the National Natural Science Foundation of China(52077004)Anhui Electric Power Company of the State Grid(52120021N00L).
文摘Aiming at the problemthat the traditional short-circuit current calculationmethod is not applicable to Distributed Generation(DG)accessing the distribution network,the paper proposes a short-circuit current partitioning calculation method considering the degree of voltage drop at the grid-connected point of DG.Firstly,the output characteristics of DG in the process of low voltage ride through are analyzed,and the equivalent output model of DG in the fault state is obtained.Secondly,by studying the network voltage distribution law after fault in distribution networks under different DG penetration rates,the degree of voltage drop at the grid-connected point of DG is used as a partition index to partition the distribution network.Then,iterative computation is performed within each partition,and data are transferred between partitions through split nodes to realize the fast partition calculation of short-circuit current for high proportion DG access to distribution network,which solves the problems of long iteration time and large calculation error of traditional short-circuit current.Finally,a 62-node real distribution network model containing a high proportion of DG access is constructed onMATLAB/Simulink,and the simulation verifies the effectiveness of the short-circuit current partitioning calculation method proposed in the paper,and its calculation speed is improved by 48.35%compared with the global iteration method.
基金Supported by NSFC(10201022,10571124,10726008)Supported by SRCPBMCE(KM200610028002)Supported by BNSF(1012003)
文摘The incidence chromatic number of G is the least number of colors such that G has an incidence coloring. It is proved that the incidence chromatic number of Cn^p, the p-th power of the circuit graph, is 2p ＋ 1 if and only if n = k（2p ＋ 1）, for other cases： its incidence chromatic number is at most 2p ＋ [r/k] ＋ 2, where n = k（p ＋ 1） ＋ r, k is a positive integer. This upper bound is tight for some cases.
基金Supported by National Natural Science Foundation of China(19831080)
文摘In this paper, a sufficient condition to partition a travel into circuits of length at least 3 is provided， In particular, a necessary and sufficient condition to partition a planar travel into such circuits, which can he verified in polynomial time, is provided，
