摘  要

本次设计完成了35kV富蕴八钢球厂降压变电站电气部分设计的总过程，设计过程中遵循国家的法律、法规，按照国家标准及规范，明确设计的目的，根据本厂用电负荷，并适当考虑生产的发展，按安全可靠，技术先进，经济合理的要求，确定35kV富蕴八钢球厂变电所的位置与型式，通过负荷计算，确定主变压器台数及数量，进行短路电流计算，选择变电所的主接线及高、低压电气设备，选择配置继电保护装置，最后按要求完成毕业设计，并绘出设计图纸。本次设计建设一座35kV降压变电站，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并以CAD辅助设计软件绘制它接线图。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。最后，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，然后进行校验并计算出系统负荷以及短路电流的数据用来选择供电设备，并且注意系统的接地、防雷以及常见故障的排除等。

关键词：35kv；化纤厂；降压；变电站；电气主接线

ABSTRACT

This design has completed the general process of the design of the electrical part of the step-down substation of 35kV Fuyun eight Steel Ball Plant. In the design process, it follows the national laws and regulations, defines the purpose of the design in accordance with the national standards and norms, and according to the power load of the factory. Considering the development of production properly, according to the requirements of safety, reliability, advanced technology and economical and reasonable, the position and type of substation in 35kV Fuyun eight Steel Ball Plant are determined, and the number and number of main transformer stations are determined by load calculation, and the short circuit current is calculated. Select the main wiring and high and low voltage electrical equipment of the substation, choose to configure the relay protection device, and finally complete the graduation design according to the requirements, and Draw out the design drawings. This design and construction of a 35kV step-down substation, first of all, according to the economic reliability of the main connection, flexible operation requirements to select the connection mode of each voltage level, in technical and economic aspects to compare, The flexible optimal wiring mode is selected and the wiring diagram is drawn by CAD software. Secondly, the short-circuit current is calculated, the short-circuit steady-state current and the short-circuit impulse current are calculated according to each short-circuit point. From the calculation of the three-phase short-circuit, when the short-circuit occurs in the working bus of each voltage level, it is obtained. The value of short circuit steady current and impulse current. Finally, according to the rated voltage and maximum voltage of each voltage grade The system load and short circuit current data are calculated to select the power supply equipment, and attention is paid to the grounding, lightning protection and the elimination of common faults of the system, etc. The equipment is selected with large continuous working current, and then the data of the system load and short circuit current is calculated.

Key words: 35kV； chemical fiber factory； step-down； substation； electric main wiring