电热耦合模型应用于干式油气套管径向温度分布计算及其试验研究

Experimental Study on Electro-Thermal Coupling Model Applied in Computation of Radial Temperature Distribution of RIP Oil-Gas Bushing Condenser

550 kV电容干式油气套管芯体温度场分布与套管长期安全稳定运行有直接关系,因此在该型套管样机试制过程中应对芯体内部径向温度分布进行研究。通过建立套管芯体电热耦合理论模型得到在线性材料条件下套管芯体径向温度分布规律,并运用电热耦合有限元模型在材料非线性条件下对理论模型进行推广,最后对套管芯体局部温度点开展试验测量研究。结果表明:550kV电容干式油气套管温度最高点位于中心导杆附近其值约为95℃;在材料非线性条件下得到套管径向温度值低于线性条件下的计算结果;额定载流量下套管芯体热击穿电压值为538kV,高于套管最高工作相电压。

Due to the direct impact of temperature distribution of 550kV resin impregnated paper （RIP） oil-gas bushing condensers on the long-term secure and stable operation of the bushings, the radial temperature distribution within the bushing condenser must be researched for the trial-manufacture of the prototype of RIP oil-gas condenser bushing. By means of establishing an electro-thermal coupling model of the bushing condenser, the radial temperature distribution law of the bushing condenser under linear material condition is derived; then applying finite element model of electro-thermal coupling the established theoretical model of radial temperature distribution is extended to the nonlinear material condition; finally experimental haeasurement of local temperature points of bushing condenser is performed. Measured results show that the highest temperature of 550kV RIP oil-gas bushing appears near center conductor and the temperature is about 95 ~C; the calculated radial temperature of the bushing under nonlinear material condition is lower than that under linear material condition; the thermal breakdown voltage of bushing condenser under rated current is 538kV, which is higher than the maximum operation phase voltage of the bushing.