新一代±800 kV/8 GW特高压直流换流阀用饱和电抗器温升试验及比对分析

Temperature Rise Test and Comparative Analysis of Saturable Reactors for New Generation of±800 kV/8 GW UHVDC Converter Valve

为研究特高压直流输电工程换流阀用饱和电抗器的温升特性,掌握内部铁芯温度分布规律,分析了现有换流阀用饱和电抗器损耗及铁芯温升计算模型,提出了基于预埋光纤温度传感器的特高压直流换流阀用饱和电抗器温升试验方法,实现了对电抗器内部全部铁芯的直接温度测量。依托新一代±800 kV/8 GW特高压直流工程,设计了高频电源等效铁芯损耗加载以及合成回路阀组件运行试验加载2种试验条件,分别测量了4种型号的换流阀饱和电抗器关键点温度,比对分析了铁芯温度分布特性。试验结果表明,2种试验加载方式下,饱和电抗器内部靠近进出水口位置铁芯温度低于其他位置的铁芯温度,各型号饱和电抗器温升特性规律基本一致;在换流阀运行条件下,各电抗器铁芯最高温度均小于90℃,外壳表面温度均小于75℃,满足工程要求。

In order to study the temperature rise characteristic of the saturable reactor for UHVDC converter valve and obtain the temperature distribution laws of the cores inside,this paper analyzes the calculation models of saturable reactor loss and core temperature rise on the basis of existing researches.A temperature rise test mothed for saturable reactors is proposed on the basis of embedded optical fibre temperature sensors,by which the temperature of all the cores inside could be measured directly.Two test conditions are designed considering the newgeneration of±800 kV/8 GW UHVDC transmission project,including the equivalent core loss loading method by high frequency power source and valve section operating test loading method by synthetic test circuit.The temperature of the key points of four kinds of UHVDC valve reactors are measured and the temperature distribution characteristics of cores inside are analyzed comparatively.The results showthat,under two test conditions,the temperature of the cores close to cooling water inlet and outlet are lower than others in one valve saturable reactor,and the temperature rise characteristics of each type of saturable reactor are basically consistent.Under operating condition,the core temperature of each type of valve reactor is lower than 90℃and the case temperature is lower than 75℃,which can meet the requirements of UHVDC project.