三相负荷不平衡的问题对住宅建筑配电的影响

Impact of Unbalanced Three-phase Load on Power Distribution of Residential Building

结合某高层住宅工程实例,介绍了动力配电箱采用需要系数法进行负荷计算的4种情况,并进行了对比分析。提出未调整三相负载平衡的配电方案相比调整三相负荷平衡的方案,会使动力配电箱的进线电缆截面大一级,增加了配电系统投资成本;在三相负载不平衡的情况下,需要系数的选择方法对选择保护开关没有影响,电气设计人员可直接按照三相配电计算所连接户数的方法选择需要系数。

Combining by a residential building project as an example,this paper introduced four load calculation schemes of power distributing cabinet by using the demand coefficient,and compared the four load calculation schemes.It is pointed out that compared with the adjusting three-phase load balancing distribution schemes,the unadjusted threephase load balancing distribution schemes should increase the inlet cable section of power distributing cabinet and the investment cost of distribution system. In the case of unbalanced three-phase load,the selection schemes of demand coefficient has no affect on the selection of protection switch. According to the three-phase distribution,the electrical designers can select the demand coefficient by calculating the total number of connected users.