To investigate the optimal radial-arranged-position of the optical fiber in the cross-linked polyethylene (XLPE) power cable, the fibers were arranged into three positions, including segmental conductor center, the insulation shield surface, and the waterproof compound center, respectively, and temperatures were measured based on the Brillouin optical time-domain reflectometry (BOTDR) technology while the thermocouples were arranged at the same positions mentioned above for comparison, respectively. Four cases of cable temperature rising experiments under the laying environments of duct and water were carried out. The conductor temperatures were calculated using the temperatures measured by the fibers at the insulation shield surface and waterproof compound center, and the differences between the calculated values and the measured temperatures by thermocouples were analyzed and compared. Results show the temperature differences at different axial positions of fibers at the insulation shield surface or the waterproof compound center were less than 0.22 °C. These were much less than the differences in different axial positions of thermocouples, among which the maximum is 4.8 °C. The maximum temperature differences between the fibers and the thermocouples at the three positions mentioned above were 4.9 °C, 3.2 °C, and 3.7 °C, respectively. The maximum transient relative differences of the conductor temperature between the calculated and measured values do not exceed 7.6% and 7.1%, respectively. And the steady-state relative differences do not exceed 2.6% and 4.7%, respectively. The insulation shield surface and waterproof compound center are recommended as the optical fiber arranged-position for calculating the conductor temperature.

为了研究交联聚乙烯（XLPE）电力电缆中光纤的最佳径向布置位置，将光纤分别布置在三个位置，分别是分段导体中心，绝缘屏蔽表面和防水化合物中心。 ，温度是根据布里渊（Brillouin）光学时域反射仪（BOTDR）技术测量的，而热电偶分别布置在上述相同位置以进行比较。在导管和水的敷设环境下进行了4例电缆温升实验。导体温度是使用绝缘屏蔽层表面和防水化合物中心的纤维测得的温度计算得出的，分析比较了热电偶计算值与实测温度之间的差异。结果表明，绝缘屏蔽表面或防水化合物中心的纤维在不同轴向位置的温度差均小于0.22°C。这些远小于热电偶在不同轴向位置的差异，其中最大值为4.8°C。上述三个位置处的光纤和热电偶之间的最大温差分别为4.9°C，3.2°C和3.7°C。计算值和测量值之间导体温度的最大瞬时相对差分别不超过7.6％和7.1％。稳态相对差异分别不超过2.6％和4.7％。