摘 要
本设计是某高层行政中心的建筑电气设计,建筑物高33米,地下一层,其主要有车库、消防控制室、变配电室、柴油发电机房和几个较大的会议室。地上九层,主要为各部门办公室、会议室、接待室等。
由于建筑电气的设计涉及的范围很广,本次毕业设计仅对大楼电气设计的部分主要内容进行设计,主要包括供配电系统设计、柴油发电机房设计、大楼部分照明设计、部分动力设计、防雷接地设计。
在对大楼进行设计前,先收集了相关的资料和参阅了相关的规范。在负荷统计过程利用了需要系数法、单位指标法等方法,再计算出各回路的计算电流,选取各级开关电器的型号,然后再按一定折扣选择导线的截面和母线的截面,接着计算出高、低压侧的短路电流,最后完成各种开关电器、电缆和母线的校验。在进行照明设计时,先对了一个房间计算了其需要的灯具数目,确定了灯具间的间距,以此来对其他房间进行布置灯具。在进行防雷接地设计时,先确定了其防雷等级,再对屋顶进行了避雷带的设计和负一层接地设计。最后介绍了一些电气安全的相关问题。
关键字:负荷计算,短路电流,照明
ABSTRACT
This Project is the electricity design for a government building. This building is 46.2m high, and the area is about 20000m2. It has one layer underground, which has a garage, and some conference rooms. There are same rooms for power distribution, fire control, diesel generating set and so on.
The electricity design for a building involves many subjects, so I only design the main parts of the electricity design for the government building. I design the systems of the power distribution, the arrangement plan of the room of diesel generating set, the grading, the dynamic force of the building and the grounding for lightening.
Before I design the electricity for the government building, I read many standards of the electricity design and all of the information of the government building. I make use of the demand coefficient method and use the unit index sign method to statistics the load. I compute the load current of each circuit and select the levels of all switches, then press certain discount choice to select the sectional area of each wire and bus bar. Later, I compute the short-circuit currents of the high-tension lines and the low lines. I also check the reliabilities of some switches, wires and bus bars to assurance the safety of the system. When designing the system of the grading, I choose a room to know the distance of two lamps. Then, I calculate the number of the lamp in the room. Last, I check the illumination of the room. When designing the system of the grading of the building, I define the level of grounding for lightening of the building. Then I design the lightning conductor of the roof and the ground wire. In the last part of the passage, I introduce some knowledge about the safety of the electricity.
Key words: loading calculate, short-circuit current, illuminate
目 录
中文摘要Ⅰ
英文摘要Ⅱ
1绪论1
1.1 工程概况1
1.2本设计主要设计内容2
2负荷分级和主接线图3
2.1负荷分级的意义3
2.2负荷分级的规定3
2.3本工程的负荷分级3
2.4主接线方案4
2.1.1对主接线的基本要求4
2.1.2 不同等级的负荷对电源的要求4
2.1.3主接线图5
3负荷计算7
3.1负荷计算的意义7
3.2.负荷计算的方法7
3.3本工程的负荷计算7
4无功功率补偿10
4.1无功功率补偿的意义10
4.2.无功功率补偿的方法10
4.3各台变压器补偿容量的计算10
5线缆的选择12
5.1线路选择条件分析12
5.2本工程配电线缆的选择13
6 变压器的选择14
6.1变压器选择的一般原则14
6.2本工程选用的变压器14
7 柴油发电机房的设计16
5.1柴油发电机容量的确定16
5.2柴油发电机房的布置16
8 短路电流的计算19
8.1计算短路电流的意义19
8.2几个重要的短路参数20
8.3短路各元件阻抗的计算方法20
8.4几个回路的短路电流计算21
8.4.1高压侧短路电流的计算21
8.4.2负一层照明回路短路电流计算22
8.4.3生活电梯短路回路电流计算23
8.4.4生活水泵短路回路电流计算25
9电器的选择和线路动热稳定校验27
9.1高压母线动热稳定的校验27
9.2高压进线电缆的选择与校验28
9.3断路器的校验28
9.4隔离开关的校验29
9.5几个低压线路热稳定的校验29
9.6电流互感器的校验29
9.7生活电梯回路电压损失计算30
10照明设计32
10.1照明设计的基本要求32
10.2照度计算32
10.3照明平面图34
11防雷接地设计35
11.1防雷分级35
11.2防雷措施35
11.3接地措施36
12电气安全37
12.1电气安全问题的提出37
12.2低压系统的接地形式37
13结论41
参考文献42