农电管理毕业论文.docVIP

110kV降压变电所电气一次系统设计（110/35/10kV，进出线数2/7/9） 摘 要 变电所是电力系统的重要组成部分，其作用在于变换电压、汇集和分配电能，因此，变电所安全可靠运行与国民经济的发展密切相关。随着电力系统装机容量和供电地域的不断扩大，同时电能质量、供电可靠性、运行经济性的要求也越来越高。随着现代文明的发展与进步，社会生产和生活对电能供应的质量和管理提出了越来越高的要求。供电系统的核心部分是变电所。因此，设计和建造一个安全、经济的变电所，是极为重要的。本次设计建设一座110kV降压变电所，首先，根据主接线的经济可靠、运行灵活的要求选择各个电压等级的接线方式，在技术方面和经济方面进行比较，选取灵活的最优接线方式。其次进行短路电流计算，根据各短路点计算出各点短路稳态电流和短路冲击电流，从三相短路计算中得到当短路发生在各电压等级的工作母线时，其短路稳态电流和冲击电流的值。然后，根据各电压等级的额定电压和最大持续工作电流进行设备选择和校验。最后进行配电装置设计和总平面布置，防雷保护的设计。 关键词：变电所；电气主接线；电气设备；防雷接地；配电装置 A DESIGN OF ELETRIC MAIN SYSTEM FOR 110kV STEP-DOWN SUBSTATION （110/35/10kV, the number of inlet and outlet 2/7/9） Abstract Substation is?an important part of?the power system, its?role is to?transform?voltage, collection and?distribution of electric energy, therefore, safe?and reliable operation of　substation?and?national economic development are closely related．With the regional power system and electricity installed capacity continues to expand at the same time power quality, supply reliability, operational economy demands increasingly high. Along with the electric power system installed capacity and power supply area continues to expand, at the same time, power quality, power supply reliability, economic operation requirements are also getting higher and higher .The core of the city power supply system is the substation. Therefore, the design and construction of?a safe,?economical?substation,?it is extremely important.?The?design and construction?of a?110kV substation?step-down, first of all, according to the main terminal?of the?economic and reliable operation?and flexible?asked to　select?various voltage levels of?wiring, technical and?economic aspects in the comparison, select the optimal flexible wiring. Second, the short-circuit?current calculation, according to the　short circuit short-circuit steady-state were calculated for each point of the impact of　current and short circuit current,?calculated?from the?three-phase short circuit obtained when the?voltage level?in?the work?of