摘要:随着经济的迅速发展，科学技术的不断进步促使社会中各行各业都在不断地发展壮大，电能已成为工业生产的主要能源和动力，做好工厂供电设计对于发展工业生产、实现工业现代化，具有十分重要的意义。本化纤厂35kv降压变电所电气设计，一是要能够满足化纤厂的工业生产和化纤厂生活用电的需要，二是要保证为本化纤厂安全，可靠的供电，技术先进和经济合理，并且同时要做好一些节能措施。

　　　 这次的设计题目某化纤厂35kv降压变电所电气设计。此设计根据某化纤厂实际的供电电源及实际用电负荷，并且适当的考虑到本厂未来生产一定的发展空间，同时要满足工厂供电的基本要求，首先，进行了对各车间计算负荷及无功补偿；确定出了各变电所的位置及个变电所变压器台数、容量和型号。其次，进行了短路电流的计算，选择和校验了各线路导线截面和变电所高低压设备选择和校验。最后，对各车间变电所及总降变电所进行继电保护整定计算及配置，且配置接地装置及防雷保护装置，同时绘制出设计的电气设计图样，完成了化纤厂降压变电所电气的设计。

关键词: 负荷计算; 短路电流计算;  无功补偿;  变压器选择;  接地装置

ABSTRACT:With the rapid development of economy, the constant progress of science and technology society in all walks of life is in constant development, electricity has become the main energy and power of industrial production, completes the factory power supply design for the development of industrial production, to achieve industrial modernization, have very important significance. This chemical fiber factory of 35 kv step-down substation electrical design, firstly can be able to meet the industrial production and the chemical fiber factory of  life needs,Secondly to ensure safe and reliable power supply as well as the advanced technology and reasonable economy, and energy saving measures.

　　　This design topic is a chemical fiber factory 35 kv step-down substation electrical design characteristic.This design according to the actual power supply of a certain characteristic and actual electricity load, And due consideration to the future development space in our  chemical fiber factory , to meet the basic requirement of the factory power supply at the same time, First of all, the computational load of each workshop and reactive power compensation; determine the location of each substation and a substation transformer sets, capacity and model.the computational load of each workshop and reactive power compensation;The location of the substation and the number, the capacity and the type of the transformer are confirmed, Secondly, for the calculation of short-circuit current; Select and check each line section and high and low voltage substation equipment selection and calibration.Finally, the configuration of substation relay protection devices, lightning protection and grounding device, at the same time, draw out the design of the electrical drawings, complete the  chemical fiber factory step-down substation electrical design.

Keywords: load calculation; Short circuit current calculation; reactive power  compensation ;   Transformer selection;   grounding device