三相交流系统中的短路电流第4部分:短路电流计算示例

[中文适用范围]： 本部分国际电工委员会技术报告旨在为在50 Hz或60 Hz三相交流系统中应用IEC 60909-0进行短路电流计算提供帮助。本文件不包括额外的要求，但提供了在正序、负序和零序系统中对电气设备建模的支持（第4条），以及在低压系统（第5条）、带有异步电动机的中压系统（第6条）以及带有辅助网络（向大量中压异步电动机和低压电动机组供电）的发电厂单元（第7条）中进行计算的实践执行。第5、6和7条中的三个示例与IEC TR 60909-4:2000中的示例相似，但已根据替换它的IEC 60909-0进行了修订。第8条中的示例是新的，反映了IEC 60909-0:2016中第6.8条的引入。第9条给出了测试网络的电路图和数据，以及根据IEC 60909-0进行的计算结果，提供了将用于计算短路电流的数字程序找到的结果与在具有发电厂单元、发电机、异步电动机和线路的四个不同电压等级（380 kV、110 kV、30 kV和10 kV）的高压网络中给出的 Ik"、ip、Ib、Ik、Ik1和ip1结果进行比较的可能性。 [外文原描述]： IEC TR 60909-4:2021 which is a Technical Report, is intended to give help for the application of IEC 60909-0 for the calculation of short-circuit currents in 50 Hz or 60 Hz three-phase AC systems. This document does not include additional requirements but gives support for the modelling of electrical equipment in the positive-sequence, the negative-sequence and the zero-sequence system (Clause 4), the practical execution of calculations in a low-voltage system (Clause 5), a medium-voltage system with asynchronous motors (Clause 6) and a power station unit with its auxiliary network feeding a large number of medium-voltage asynchronous motors and low-voltage motor groups (Clause 7). The three examples given in Clauses 5, 6 and 7 are similar to those given in IEC TR 60909-4:2000 but they are revised in accordance with IEC 60909-0, which replaces it. The example given in Clause 8 is new and mirrors the introduction of the new 6.8 of IEC 60909-0:2016. Clause 9 gives the circuit diagram and the data of a test network and the results for a calculation carried out in accordance with IEC 60909-0, to offer the possibility for a comparison between the results found with a digital program for the calculation of short-circuit currents and the given results for and in a high-voltage network with power station units, generators, asynchronous motors and lines in four different voltage levels 380 kV, 110 kV, 30 kV and 10 kV. This second edition cancels and replaces the first edition published in 2000. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) adaption to IEC 60909-0:2016; b) addition of an example for the calculation of short-circuit currents of wind power station units; c) correction of errors.