同通道敷设多回单芯电缆金属护套感应电压与环流计算模型研究

Research on Calculation Model of Induced Voltage and Circulating Current in Metallic Sheaths of Multiloop Single-core Cable Laying in the Same Cable Channel

随着城市电缆通道资源的日益紧缺,多回电缆同通道敷设成为电缆线路建设和运行必然面对的问题。目前尚缺乏对多回单芯电缆线路同通道敷设时金属护套感应电压与环流进行研究。根据单芯电缆交叉互联单元的等值电路,分析了单回路电缆金属护套感应电压与环流的计算模型。结合电缆敷设的实际情况,考虑了线芯电流不平衡、交叉互联单元内段长和敷设间距以及排列方式不同等因素的影响,推导出多回电缆同通道敷设时金属护套感应电压与环流的计算模型。

With the increasing shortage of cable channel resources in the cities, multi - circuit cables laying in the same cable channel is the inevitable problem in the construction and operation of cable lines. There is short of the researches on the calcu- lation model of induced voltage and circulating current in metallic sheaths for multi - circuit cables laying in the same cable channel at present. According to the equivalent circuit of single - core cable with cross - bonding connection unit, the calcula- tion model of induced voltage and circulating current in metallic sheaths is analyzed. In accordance with the actual situation of cable laying, the calculation model of induced voltage and circulating current in metallic sheaths of multi - loop cable laying in the same cable channel is deducted, considering the imbalance of conductor current and the influences of cross - bonding con- nection unit with different segment length, laying spacing and arrangement etc.