Research On Sizing And Locating Of Distributed Generationsin Distribution Network

With the rising of people’s living standards,the demand for electricity is increasing as well.In order to ensure the needs of power supply,energy sector’s requirements of the quality and reliability of electricity power supply are getting higher and higher.During recent years,the proportion of thermal power is relatively reduced.Development of nuclear power received a certain limit as a result of its high risk.Distributed power is gradually rising because of its unique characteristics in the situation as gradual increasing of electricity consumption.The accessing of the distributed power supply caused a series of serious effects on the power loss and voltage limits of the grid,and greatly increased the short circuit capacity.However,for the underdeveloped areas,especially remote areas such as agriculture and animal husbandry and mountainous areas,the development of centralized supply and demand network requires a huge investment and construction cycle,and distributed power generation technology can make up for such difficulties.Therefore,the distributed power supply installation location,capacity and power grid structure should be fully planned to consider,so that the distributed power supply will play a positive role.Reasonable planning and designing of distributed power supply is now particularly important to effectively improve the utilization of distributed power supply and improve the safety and stability of the power grid.This thesis introduced several common distributed power generation technologies,including solar photovoltaic cells,wind power generation,fuel cells and micro-gas turbines,it also introduced their working principles,advantages and disadvantages.This thesis also analyzed the influence of distributed power supply on power grid power system,relay protection,power quality and so on.Finally,according to the requirements and impact of different aspects of the distributed power supply,accessing to the grid capacity requirements were described.Based on the distributed power supply and load characteristics,the influence evaluation method of the distributed power receiving capacity was studied from the aspects of the carrying capacity of the distribution network,the short circuit current and the voltage level,and the related mathematical model have been established.And then a mathematical model and a tidal current calculation method was established for different generator models.A new optimization objective function was proposed,and three kinds of decision indexes were proposed to determine the location of the distributed power supply for the influence of the voltage level,the power level and the short circuit current level of the distributed power supply.In addition,the weight coefficient index was introduced,and its detailed specification was processed to ensure the accuracy and practicability of the optimization result.According to the mathematical model of Chapter 3,the simulation model of Tanghui substation in Jinzhai area was established,and the acceptance of 35 kV,10kV and 380 / 220 V was analyzed respectively.Based on the analysis results,using the above access principle and method,the distributed power supply access location and capacity were analyzed.The simulation results has a certain applicability.Finally,for the characteristics of the region,this thesis provided access to distributed power measures effective advice.