母线槽工频阻抗的数值计算和测量

母线槽在建筑物的低压配电系统中常被用作配电干线,其工频阻抗参数的确定对这种配电系统的设计和运行分析具有重要意义。作研究了工程中常用的铁外壳母线槽的工频阻抗,提出用“等效相对磁导率”方法建立母线槽的近似线性仿真模型,基于该模型采用边界元方法的商业软件对其工频阻抗进行数值计算,并介绍了“等效相对磁导率”的确定方法;对两种实际母线槽的工频阻抗进行了数值计算和实验测量,证明了这种阻抗估算方法的可行性和有效性;应用这种阻抗估算方法分析了母线槽的有关参数对其阻抗的影响,并据此提出了一些母线槽的设计建议。

NUMERICAL CALCULATION AND MEASUREMENT OF POWER FREQUENCY IMPEDANCE FOR BUSBAR TRUNKING SYSTEMS

The power-frequency impedance of busbar trunking systems, which are often used as risers in buildings, is an important parameter in the design of distribution system and performance prediction. This paper deals with the impedance simulation and measurement of busbar trunking systems, where iron or galvanized iron material exists. A lin- ear numerical simulation model is developed in which the iron or galvanized iron trunking is approximated as"linear" mate- rial with a constant "equivalent relative permeability", which can be determined through magnetic field measurements. Based on the model, impedance simulation was carried out by use of a boundary element - method (BEM) software. The practicability and effectiveness of such simulation method is validated with laboratory measurements. The impedance im- pact of some busbar trunking parameters is investigated. Some busbar trunking design suggestions are also provided.