| With the gradual formation of the electricity market, the customers' demands for supply of power have become much greater than ever before. The most important way to supply the reliable, high-grade, appropriate-priced electric energy is to employ the distribution system automation (DSA). To display sufficiently the functions of DSA, improve security and economical efficiency of the running of distribution system, and achieve a sound analysis as well as an accurate decision-making process, at first, it's necessary to master the running state of distribution system and supply the reliable, overall and real-time running module to the other application software. In this paper, a concept of running state analysis of distribution system is defined, and the modern mathematic analytical methods and artificial intelligent theories are used to study especially the running state of distribution system. The chief research work of this paper is as follows:1. On the basis of state estimation of distribution system in possession, according to the characters of distribution system, a new algorithm of the fast decoupling asymmetrical three-phased state estimation for distribution system on phase coordinates is proposed and the decoupling compensation modeling which is used for asymmetrical three-phased load flow is introduced in this paper. According to the characters of iterate equation, the equation of asymmetrical three-phased state estimation can be decoupled strictly on phase coordinates, and with the rotation transformation added, the real and image part of normal equation can also be strictly decoupled. The algorithm will not only save the advantages of equivalent current measurement varying algorithm, but also improve its disadvantages, so it has better application in the future.2. Bad data detection and identification is one of the chief functions in the running state analysis of the distribution system. Because of the indeterminacy of measure data in distribution system, a new method for identifying bad data-transitive closure method is proposed by using the modern fuzzy theory. It uses the standardresidual rN and the difference △z of measure values between adjacent sampling houras two kinds of eigenvalues to do fuzzy and clustering analysis. With the calibration formulation, the similarity coefficients which describe the extent of measure values belonging to bad data can be calculated, and the fuzzy equivalent matrices can be obtained via square method, then the bad data can be identified via λ cut matrices. Theexample proves this method effective and feasible.3. On the basis of fault location in distribution system in possession, two kinds of methods of fault location in distribution system are proposed in this paper: a unified matrix algorithm for fault location and a refined genetic algorithm for the fault location in distribution system. Because of the disadvantages of traditional unified matrix algorithm, the first one uses the directed graph to describe distribution system, and in this way it can avoid matrices multiplication and normalization. The second one creates a new evaluation function, and set up a new and more suitable mathematic modeling for distribution system, it not only avoids misjudge, but also has more powerful fault-tolerance.4. On the basis of reconfiguration algorithms of distribution system in possession, a new reconfiguration algorithm based on dynamic particle swarm optimization (DPSO) is proposed in this paper. It adopts the voltage stability of distribution system as the object function, and uses the improved particle swarm optimization algorithm which can trace dynamically the environment's change to make the real-time dynamically reconfiguration of distribution system, and proposes a new coded form which divides the particle module according to the topological structure of distribution system, and then avoids the convergence precociously via the community characters of DPSO. Finally, it is compared with the genetic algorithm, the result of which sh...
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