Evaluation Of Medium Voltage Distribution Network Structure Based On Theories Of Complex Networks

With the deepening transformed to power grids, the theory of the medium voltage distribution network planning has been further developed and rich. Determination of network structure determines the most essential things of the medium voltage distribution network. It has great significance to provide safe and high quality supply service. Therefore, the choice of network structure has been an urgent solution Problem of the medium voltage distribution network planning. It has been an problem to choose a high-security, high power quality, modern high-tech and other performance medium voltage distribution network structure to meet the development needs of the times, to meet modern building requirements, which must be solved.In the reality, it is constrained by the regional economic development, the load density, the geographical environment, the corridor limits, the line of cable, the distribution automation, the distributed power access, the resistance of serious natural disasters, the financial constraints and many other factors to select the network structure. In order to solve the structure selection problem of the medium voltage distribution network, we do the following:(1) The collection of the typical voltage distribution network structure is established, and the characteristics, natures, scopes of each network structure are summarized with the cable of the city, the distribution automation of distributed power networks, the actual situation of the access point trends.(2) The factors affecting network structure selection are studied. The differentiated design theory of the medium voltage distribution network is proposed on the basis of the summary of the main affecting factors, which concludes the scene design, design principles, designed aim, etc. It provides the necessary premise for a reasonable choice of the network structure.(3) Based on the complex network theory, a new index for the reliability evaluation of the network structure - invulnerability is obtained, and the invulnerability model for medium voltage distribution network structure is established. Finally, an assessment of invulnerability for the typical network structure is achieved.(4) In constraints of the differentiated design, the economy, invulnerability and other indexes are successfully calculated, and incorporated into evaluation index system. The optimal network structure consistent with the development of the times and the regional reality is achieved, through quantitative assessment of network structure by combining analytic hierarchy process method and fuzzy comprehensive evaluation method.