摘要
对低压动力电缆选择计算中容易忽视的要点进行了探讨、分析,指出了导体阻抗计算中直流电阻和交流电阻的关系,强调了应根据电气保护校核电缆截面;以炼化企业常用的交流聚乙烯绝缘电缆为例,给出了电缆导体最高允许温度、建议的实际工作温度;同时介绍了一种短路时导体假设计算温度的计算方式,并通过计算,给出了低压回路动力电缆短路时导体假设计算温度和电阻值的变化趋势。
This paper discusses and analyzes the key points which may be easily ignored in the selection and calculation of low-voltage power cable,points out the relation between DC resistance and AC resistance in the calculation of conductor impedance,and emphasizes that the cable cross-section shall be verified by electrical protection.Taking the widely used XLPE insulated cable as an example,this paper specifies the maximum conductor temperatures and the recommended actual working temperature.This paper also introduces a calculation method for the assumed temperature in case of short circuit of conductor,and gives the trends of the calculated assumed temperature of conductor and the relevant resistances in case of short circuit of low-voltage power cables.
作者
李玲
Li Ling(SINOPEC Engineering Incorporation,Beijing,100101)
出处
《石油化工设计》
CAS
2023年第2期10-14,20,I0001,共7页
Petrochemical Design
关键词
电缆和导体
导体的直流电阻和交流电阻
导体最高允许温度
导体实际工作温度
导体短路时假设温度的计算
导体短路时的电阻值
低压回路末端短路电流
cable and conductor
DC resistance and AC resistance of conductor
maximum allowable temperature of conductor
actual working temperature of conductor
calculation of assumed temperature in case of short circuit of conductor
resistance when the conductor is short circuited
short circuit current at the end of low-voltage circuit
