Two-Phase Optimal Planning For Substation Locating And Sizing

With the rapid development of expansion and reform of urban power systems inChina, urban power system planning has become an urgent task. It has become animportant process to acquire the substation location and size in urban power systemplanning. And the result of planning will affect network structure, the power supplyquality and the operation economic level in future.The target of the traditional substation planning is to seek for the lowest operationexpenses maintaining all the technical constrains. However, from the perspective ofengineering practice, the substation sites which are decided by the approach ofignoring geographical information usually lie in the region unsuitable for building upsubstations, such as lake, street, mall, and so on. Therefore, the planning result mustbe reconsidered. When the site number of regulation is large, adjustment of some siteswill change the associated load and service area of surrounding substations, and evenaffect the economy of the whole project. So obtaining the final project is noteconomic optimal result, accordingly decline the validity of traditional approach.Focusing on the insufficiency of the traditional method, a practical two-phaseoptimal approach for substation planning is proposed. Firstly, the initially substationplanning project is obtained without incorporating the geographical information;secondly, the surrounding geographical information is considered in detail, and thegeographical fitness is obtained using AHP. Then the global fitness of every project isevaluated associated with the economical fitness and finally the more reasonableproject is acquired. Some engineering examples indicate that the approach can meetthe practical planning requirements all the better.