随着国民经济的快速发展，各行各业对电能的需求日益增加，而变电站作为电网

随着国民经济的快速发展，各行各业对电能的需求日益增加，而变电站作为电网的重要组成部分，变电站的安全可靠运行与国民经济发展密切相关。本文设计了一个降压变电站，此变电站有三个电压等级：高压侧电压为110kV，有一回线路；中压侧电压为35kV，其中有一回联络线路；6kV线路主要为4台LF路供电。本文的主要工作：根据杭州市电力局提供的系统参数，计算短路电流，从而确定110kV、35kV、6kV以及所用电的主接线方式；通过负荷计算及供电范围确定了主变压器、所用变台数、容量及型号，同时也确定了一次设备的规格、型号等；变电站的二次系统按照无人值守的要求进行设计，变电站电气设备的保护装置主要采用杭州华光生产的CSR系列保护装置，使变电站能够实现“四遥”。通过对LF炉正常生产时产生的最大无功冲击的计算，为满足LF炉冲击性负荷的安全供电，本设计采用动态无功补偿，提高了电能质量，并达到节能的目的。

随着国民经济的快速发展，各行各业对电能的需求日益增加，而变电站作为电网的重要组成部分，变电站的安全可靠运行与国民经济发展密切相关。 本文设计了一个降压变电站，此变电站有三个电压等级：高压侧电压为110kV，有一回线路；中压侧电压为35kV，其中有一回联络线路；6kV线路主要为4台LF路供电。 本文的主要工作：根据杭州市电力局提供的系统参数，计算短路电流，从而确定110kV、35kV、6kV以及所用电的主接线方式；通过负荷计算及供电范围确定了主变压器、所用变台数、容量及型号，同时也确定了一次设备的规格、型号等；变电站的二次系统按照无人值守的要求进行设计，变电站电气设备的保护装置主要采用杭州华光生产的CSR系列保护装置， 使变电站能够实现“四遥”。 通过对LF炉正常生产时产生的最大无功冲击的计算，为满足LF炉冲击性负荷的安全供电，本设计采用动态无功补偿，提高了电能质量，并达到节能的目的。

With the rapid development of the national economy, the demand for electric energy in all walks of life is increasing. As an important part of power grid, the safe and reliable operation of substation is closely related to the development of national economy. In this paper, a step-down substation is designed, which has three voltage levels: the high-voltage side voltage is 110KV, there is a circuit line; the medium voltage side voltage is 35kV, in which there is a tie line; 6kV line mainly supplies power for four lf circuits. The main work of this paper: according to the system parameters provided by Hangzhou Electric Power Bureau, the short-circuit current is calculated, so as to determine the main wiring mode of 110kV, 35kV, 6kV and the power used; through the load calculation and power supply range, the number, capacity and model of the main transformer, used transformers are determined, and the specifications and models of the primary equipment are also determined; the secondary system of the substation is unattended The protection device of electrical equipment in substation mainly adopts CSR series protection device produced by Hangzhou Huaguang, which enables the substation to realize "four remote". According to the calculation of the maximum reactive power impact produced during the normal production of LF furnace, in order to meet the safety power supply of the impact load of LF furnace, the design adopts dynamic reactive power compensation to improve the power quality and achieve the purpose of energy saving.<br>