换流变压器谐波损耗的计算与分析

换流变压器是高压直流输电系统的重要设备,准确计算换流变压器的谐波损耗,具有十分重要的意义。笔者在分析换流变压器结构与性能特点的基础上,利用Magnet建立时谐场简化计算模型,通过有限元方法对换流变压器绕组和金属结构件中产生的谐波损耗进行了仿真计算,得到了在高次谐波电流下谐波损耗的数值并与测量结果和IEC 61378-2—2001法所计算的结果进行了比较。结果表明:仿真的结果与IEC61378-2—2001法所计算的结果相比更接近实测值,能够满足工程设计要求。在此基础上,对加铜屏结构下的谐波损耗值与未加铜屏时的结果进行了对比和讨论。

Calculation and Analysis of Harmonic Loss in Converter Transformer

Based on analysis of structure and characteristics of converter transformers,a simplified calculation model of time-harmonic field is established by means of the software Magnet.The harmonic losses in windings and metal structural components of a converter transformer are calculated with finite element method,thus the values of harmonic losses under higher-order harmonic current are obtained and compared with measured data and calculated values from the method in IEC 61378-2—2001.The results show that: compared with the values from IEC 61378-2—2001,the simulation ones are more close to the measured data,and meet the requirement of engineering design.Moreover,the harmonic losses of the metal structural components with and without copper shield structure are compared and discussed.