坚强智能电网高压电缆芯暂态温度实时监测方法研究

Research on Real Time Monitoring Method of High Voltage Cable Core Transient Temperature in Strong Smart Grid

为了准确监测智能电网高压电缆芯暂态温度,研究坚强智能电网高压电缆芯暂态温度实时监测方法。依据背向拉曼效应中代表温度的反斯托克斯光与斯托克斯光比值,基于光频域反射(OFDR)的电缆芯暂态温度检测结构建立高压电缆芯暂态热路模型,并依据电缆各截面等温、电缆芯厚度与电缆芯热阻值受热阻系数影响等模型假设条件简化该模型,利用频域分析法计算电缆芯暂态温度。实验表明:高压电缆芯的温度可通过线芯电流和电缆绝缘层温度综合展现;该方法监测温度数值与实际温度数值误差为±0.1;不同电磁干扰下该方法监测温度曲线与实际温度曲线相差不大,受电磁干扰影响较小;滤波前后,该方法均可准确监测温度变化情况,具备较好电缆芯温度监测效果。

In order to accurately monitor the transient temperature of high-voltage cable core in smart grid,a real-time monitoring method of high-voltage cable core transient temperature in strong smart grid is studied.According to the ratio of anti Stokes light and Stokes light representing temperature in back Raman effect,the transient thermal circuit model of high voltage cable core is established based on the optical frequency domain reflection(OFDR) transient temperature detection structure.The model is simplified according to the assumptions of isothermal temperature of each section of the cable,the influence of thermal resistance coefficient on the thickness of cable core and thermal resistance of cable core.The transient temperature of cable core is calculated.The experimental results show that the temperature of the high-voltage cable core can be displayed by the core current and the cable insulation temperature;the error between the measured temperature value and the actual temperature value is less than ±0.1.Under different electromagnetic interference,the temperature curve monitored by this method has little difference with the actual temperature curve,and is less affected by electromagnetic interference.before and after filtering,the method can always accurately monitor the temperature change,and has good monitoring effect on cable core temperature.