金属氧化物限压器冷却结构设计及其三维温度场仿真分析

Cooling Structure Design of Metal Oxide Voltage Limiter and Simulation Study of Its Three Dimensional Temperature Field

电力系统发生短路故障时,巨大的短路能量注入到金属氧化物限压器(metal oxide voltage limiter,MOV)上,导致其温度快速升高。为保证MOV的可靠运行,延长其使用寿命,需要尽快散热降温。因此,MOV冷却结构的设计和了解MOV的温度分布非常重要。为此,提出了一种新型MOV冷却结构,并基于传热学的理论建立了MOV三维温度场有限元法计算模型。用有限元计算软件ANSYS系统地计算分析了MOV冷却通道的直径、条数和分布等几何量对于通风道内传热特性的影响。结果表明:这种新型冷却结构的MOV要比传统MOV的散热能力更好,MOV散热能力随冷却通道直径不同而变化,通道直径存在约10 mm的最优值,此时冷却结构散热效果较好,4条冷却通道比2条冷却通道具有更好的散热效果。

During the short-circuit fault in power system,a huge short-circuit energy will inject into metal oxide voltage limiter（MO） mandrel,leading to the rapid temperature rise of MOV.To ensure the reliable running of MOV and to extend its service life,MOV needs to cool as soon as possible.Therefore,MOV cooling structure with the excellent cooling efficiency and the knowledge for the temperature distributions of MOV mandrel are of essential importance.We proposed a new cooling structure of MOV,and established a finite element model of MOV 3D temperature field based on the theory of heat transfer.For the proposed cooling structure of MOV and the calculation model,the systematical calculations and analyses of the influences of the diameter,numbers and distributions of the cooling channel on the heat transfer were performed using the finite element software ANSYS.It is shown that the efficiency of the cooling structure can be changed by changing its diameter,there is an optimum diameter of 10 mm,where the good cooling efficiency is obtained,and the efficiency of cooling structure with the four channels is superior to that with the two channels.