浅谈高层建筑供配电系统设计
摘要：随着城市规模的不断发展，高层建筑越来越多，因此，高层建筑电气设计就成为设计者不得不面对的问题。本文结合工程实例，介绍了高层建筑电气设计中一些比较典型且具有普遍意义的问题，结合某工程的实际做法阐述了问题的解决方法。
关键词：高层建筑；电气设计；配电；负荷计算 1工程概况
本项目商业综合大楼，总建筑面积为405570m2，地上建筑面积272330m2，地下建筑面积133240m2,主体高度99m。项目组成为：办公楼两座，建筑面积为70800m2，28层，标准层高为3.2m。 2 负荷计算
1）负荷特点:用电负荷大,远大于《全国民用建筑工程设计术措施》中大120W/m2的指标,尤其是餐饮的用电负荷更大，而且不同类型、不同饮食文化背景的餐饮差别也很大。
2）负荷的不确定性大，因为商业地产往往根据市场租的需求，不断调整商铺的性质，使得负荷在动态变化之中。
3）目前的规范和技术措施没有对商业项目中不同类别商铺的参数指进行细化，工程设计中的负荷计算缺少据，大多数情况只能靠设计人员凭借以往工程经验进行计算。
负荷参数的选择：针对以上遇到的问题，进行负荷计算时，首先与开发商销售部门进行良好的沟通，确定各层的业态形式商铺面积和性质，这是电气负荷计算的基础依据；其次确定商铺内单位面积参数指标也很重要且复杂，因为规范中没有明确的指标可以参考；而且不同城市间的经济发展水平不均衡，用电指标也不同；便在同一城市不同区域的消费群体也有差异。
3）需要系数的选择：参数确定后，需要进行负荷计算。一般采用需要系数法，计算过程不再赘述。需要探讨的是需要系数的选择，这在现行规范、手册及《统一技术措施》中也没有明确的要求，根据多年的设计体会认为，在配电最末端商铺内户箱或层配电箱计算时Kx一般取1，在各回路干线计算时取0.7～0.8，在变电所各配电变压器计算时取0.4～0.6。 3变电所设置
根据负荷计算结果，本工程的变压器总安装容量为43400Kv.A，经与供电公司反复协商，分别在本工程的北、中和南三段设置3个变电所为三段建筑供电，1#变电所设6台2500Kv.A变压器,承担北段供电；2#变电所设4台1600Kv.A变压器,加6台2000Kv.A变压器,承担中段的供电，另外还有5台10Kv.A高压冷水机组（合计4000Kv.A）；3#变电所设2台2000Kv.A加2台1000Kv.A变压器，承担南段A、B两座办公楼供电。本工程配置两处10Kv电源引入点，每处为两路10Kv线路,根据供电公司对10Kv电源容量的规定：每路最大负荷为11000Kv.A左右，两路即为22000Kv.A，设计1#、3#变电所合用一处10Kv,电源进线，总容量为21000Kv.A；2#变电所内变压器和10Kv,冷水机组共用一处10Kv电源进线，总容量为22400Kv.A。在变电所平面布置的设计中，除了满足规范要求以外，还需要考虑高压柜、变压器和低压柜按供电顺序布置，尤其是低压配电柜馈出电缆
的走向顺畅，值班人员巡视方便等问题如不认真考虑，会造成施工时电缆交叉多、绕远路、浪费建筑面积以及巡视不方便等问题。 4较小消防负荷的供配电
在大型商业项目设计中经常会遇到消防用电设备负荷较小且分布较分散，若均由变电所馈出，会使得变电所低压柜馈出很多小电流回路，对断路器分断能力和导体的动、热稳定带来一定的影响。根据GB50045-1995《高层民用建筑设计防火规范》规定“消防用电设备应采用专用的供电回路，其配电设备应设有明显标志”。对供电回路的条文解释系指“从低压总配电室（包括分配电室）至最末一级配电箱，与一般配电线路均应严格分开”。在本设计中，采用了增加一级配电的方法，即从变电所不同母线段上分别馈出一条消防专用回路，在适当位置设置两台配电柜，再由此配电柜放射式配至末端双电源互投箱，这样既满足了规范对专用供电回路的要求，又避免在变电所级馈出许多小电流回路。 5断路器及导体的选择
由于商业地产项目房间用途的不确定性，在选择断路器和导体时必须考虑一定的裕量以满足调整造成的负荷变化。根据这一特点，在设计中较多地使用了插接母线供电，既可以满足大载流量的要求，又使供配电灵活性加大，在每层竖井中均预留备用插接箱，以便在变化时，可根据上下层负荷的变化，进行调整。例如：某竖井一段母线负责1～3层供电，当1层由于变化容量增大，而3层容量减小时，就可使用1层的备用插接箱把3层富裕的容量配给1层使用。在变电所这级配电中，选择断路器时要选整定值可调整的断路器，以便在末端负荷变化时调整整定值；在母线和互感器的选择上一般按断路器框架值来选。例如：某段干线设备容量530Kv，Kx取0.7，计算电流为704A，选择断路器框架值为1000A，整定值为800A；电流互感器为1000/50；母线载流量为1000A，此路最大可满足1000A电流的负荷使用要求，即便有调整，配电开关及线路也可不必作大的变动。 6层配电箱的设置
根据各层防火分区的划分，分别在各层编号为A～K竖井内设置层照明配电箱为各商铺供电,各商铺的供电采用一对一放射式供电。需要指出的是由于各层的业态比较复杂各层的防火分区上、下层不对应，使得有的竖井在负责本防火分区供电的同时，还要负责相邻的防火分区的供电。在设计时，采用了就近原则，同时也考虑到整条干线负担的负荷情况，尽量使各个竖井内负荷比较平衡。 7公共区域配电箱的设置
考虑到商业的公共区域将来需要二次装修，必须预留电源。此处的设计需要考虑以下几点：①电量预留多少的问题，其中照明用电可根据GB50034-2004 《建筑照明设计标准》表6.1.3及其6.1.8条，商业建筑照明功率密度值计算，高档超市营业厅为20W/m2，根据“装饰性灯具总功率50%计入照明密度计算值”的规定，采用的预留标准为40W/m2。②为方便装修设计，在每个防火分区内设置了公共区域照明配电箱和应急照明配电箱，以便明确装修设计的电气配电分界点。
③将楼梯间、储藏间等不需要做装修的部位，单独设置配电回路或配电箱，尽量不从公共区域预留精装用电的配电箱内馈出。 ④公共区域照明的控制，大部分采用两种方式，即C—BUS系统或BA系统控制，利用C—BUS的优点是控制比较灵活，可按每一路馈出控制，也可调光控制；缺点是造价较高。利用BA系统控制优点是造价低，控制简单；缺点是由于交流接触器为三相，控制时可能会三路同时开或者同时关，在装修设计时需将各接触
器馈出回路岔开供电，避免造成故障时大面积停电。 8户配电箱的设计 在商业地产设计中，往往只为商铺设计一个电表箱，而出线回路由用户根据自己的需要进行二次设计，但是商铺内风机盘管的供电很难解决，无法进行空调系统的整体调试。本工程的做法是在电表箱内增加一个断路器为风机盘管供电，另一路为用户二次设计时使用，如下图所示。 用户配电箱设计图
9配电柜/箱与配电回路的编号
大型项目往往低压配电柜/箱很多，低压馈出回路就更多，往往会出现柜/箱编号及线路编号重复的问题，造成在设计图中查找及将来维护检修的困难。本工程有3个10Kv变电所，20台变压器，上百台低压馈出柜，馈出回路更多。按照国际电工委员会（IEC）及中国国标的要求：①所有的配电编号要简单明了，不能太箱和线路编号不重复。②编号要简单明了，不能太长。③区分负荷性质和类型。④规律明显便于查找，能使看图者一目了然。根据以上要求及地上、地下建筑防火分区和业态形式的不同情况，采用了两种略有差别的方式。地下部分基本为车库，用途比较单一，防火分区也比较整齐，按防火分区编号，如AL—BL—1/1、AP与APE等各字母及数字含义：AL代表照明配电箱（AP代表动力配电箱，APE代表应急动力配电箱）；BI代表地下一层；1/1代表I防火分区1号箱。地上部分比较复杂，防火分区比较多，且上、下层防火分区不对应，按竖井编号较好，如AL—1—A1、AP和APE等字母及数字含义：1代表一层；A1代表A号竖井馈出的1号配电箱。低压馈出回路的编号采用了如：W3—6—AL—1—A1，W3—6)表示此回路由3号变压器所供电的6号配电柜馈出，AL—1—A1表示本回路所接的第一个配电箱为AL—1—A1等，以此类推。 10结束语
随着商业设计项目越来越复杂，需要设计人员不断地提高设计水平，精心设计，作出精品。以上仅是在商业设计中的点滴经验总结，希望能和广大设计人员交流
Power supply system of high-rise building design
Abstract: With the continuous development of city size, more and more high-rise buildings, therefore, high-rise building electrical design to the designers had to face. In this paper, an engineering example, describes the electrical design of high-rise buildings and some of the more typical issues of universal significance, combined with the actual practice of an engineering solution to the problem described.
Key words: high-rise building; electrical design; distribution; load calculation 1 Project Overview
The commercial complex project, with a total construction area of 405570m2, on the ground floor area of 272330m2, underground construction area of 133240m2, the main height of 99m. Project components are: two office buildings, construction area is 70800m2, 28 layers, the standard story is 3.2m. 2 Load Calculation
1) Load characteristics: electric load, much larger than the \civil engineering technical measures\Large 120W/m2 indicators, especially in the electricity load more food, and different types of food and beverage catering different cultural backgrounds also high.
2) the uncertainty of a large load, because the commercial real estate rents are often based on market demand, and constantly adjust the nature of the shops, making the load in the dynamic changes.
3) There is no specification and technical measures in the different types of commercial projects refer to the detailed parameters of the shops, engineering design load calculation in the lack of data, in most cases to rely on staff with previous experience in engineering design calculations.
Load the selection of parameters: for the above problems, the load calculation, the first developer of sales and good communication, to determine the form of layers of the forms and nature of floor area, which is calculated on the basis of electrical load basis; followed to determine parameter index within the unit area of shops is also very important and complex because there is no clear indicator of the specification can refer to; and different levels of economic development between cities is not balanced, power indices are also different; will be in the same city, different regions have different consumer groups .
3) the need to factor in the choice: parameters determined, the need for load calculation. Need to factor commonly used method, the calculation will not repeat them. Need to explore is the need for coefficient selection, which in the current specifications, manuals and the \design experience that most end shops in the distribution or level within the household distribution box with case Kx generally take a while, in the calculation of the loop route to take 0.7 to 0.8, the distribution transformers in the substation calculations take 0.4 to 0.6. 3 substations set
Load calculation based on the results of this project the total installed capacity of transformer 43400Kv.A, after repeated consultations with the power company,
respectively, in the project in northern, central and southern three sections set the three buildings into three power substations, 1 # set 6 sets 2500Kv.A transformer substation, take the northern section of power supply; 2 # 4 1600Kv.A transformer substations located, plus 6 sets 2000Kv.A transformers, take the middle of the power supply, in addition to 5 Taiwan 10Kv.A high-pressure water chillers (total 4000Kv.A); 3 # substation located 2 units plus 2 units 1000Kv.A 2000Kv.A transformers, take the southern section of A, B two office supply. 10Kv power configuration of this project into two points, each at the two 10Kv lines, the power company under the provisions of 10Kv power capacity: maximum load per channel is about to 11000Kv.A, two is the 22000Kv.A, design # 1 , 3 # combination of a substation 10Kv, power line, with a total capacity of 21000Kv.A; 2 # substation transformers and 10Kv, 10Kv chillers sharing a power line, with a total capacity of 22400Kv.A. The design of the substation layout, in addition to meeting regulatory requirements, it also need to consider the high-pressure cabinets, transformers and low voltage power supply cabinet by order of arrangement, especially in low voltage distribution cabinet to feed the cable smooth and easy inspection duty problems are not seriously consider the construction of the cable crossing will cause more long detour, a waste of floor space, and convenient inspections and other issues. 4 small fire load power supply
In the design of large commercial projects often encounter small fire load of electrical equipment and more dispersed distribution, if fed by a substation, a substation will be fed a lot of low-voltage low-current counter circuit breaking capacity circuit breaker and conductor of the dynamic and thermal stability in a certain extent. According to GB50045-1995 \protection design of tall buildings,\rule \be used in Fire Equipment dedicated power supply circuit, the power distribution equipment shall be provided with clear signs.\Interpretation of the provisions of the power supply circuit means \room) to last a distribution box, and the general distribution lines should be strictly separated.\different from the substation bus segments, respectively, a fire fed a special circuit, set in place two distribution cabinets, distribution cabinets and then the resulting radial allocated to the end of the dual power to vote each box, so that not only meets the specification requirements for dedicated power supply circuit, but also to avoid feeding the substation level of many small current loop.
5, the choice of circuit breaker and conductor
Commercial real estate projects use the room as the uncertainty in the choice of circuit breakers and conductors must be considered in a certain margin to meet the needs caused by adjustment of the load changes. According to this characteristic, increased use in the design of the plug bus-powered, not only meet the requirements of large carrying capacity, and also allows the flexibility to increase supply and distribution, are reserved in each shaft in the plug-box backup in order to change, according to changes in upper and lower load, to adjust. For example: a bus is responsible for a shaft 1 to 3 layers of power, when a layer due to the change in capacity increases, while the 3-layer capacity is reduced, you can use a spare plug box layer off the 3-layer 1 layer capacity rationing . This level distribution in the substation, select the circuit breaker to choose the setting
外文文献及翻译--浅谈高层建筑供配电系统设计
