10kA高温超导电缆系统绝缘

System Insulation for 10kA High-temperature Superconducting Cable

为确定10kA直流高温超导电缆(10kA超导电缆)本体和测控系统绝缘水平,讨论了其本体结构特点和电场分布特点以及绝缘水平的影响因素;对Pt100型铂电阻温度传感器进行了耐压、耐流试验;构建了由模型电缆和模拟测控回路组成的系统并对其进行耐压试验。结果表明温度传感器在5kV情况下耐压情况良好,但较大电流容易导致其损坏;高压下普通密封转换端子外壳对温度传感器针脚放电并导致传感器损坏,需设计专用密封端子。研究认为10kA超导电缆本体绝缘设计需适当提高绝缘耐压水平,测控系统浮电位设计满足10kA超导电缆工作状态下的测控需要,但测控系统绝缘设计中需防止产生因高压产生的局部放电电流加载于测量回路,10kA超导电缆系统集成后进行的系统耐压测试表明其绝缘系统满足运行要求。

In order to determine the insulation level both for the 10kA DC high-temperature superconducting（HTS） cable（10kA superconducting cable）and measurement and control system,we discussed the characteristics of structural features,electric field distribution of 10kA HTS cable,and impact factors of the insulation level;and experimentally researched voltage withstands and the current for Pt100 platinum resistance temperature sensor.Moreover,we built a testing system compoed of a model cable and analog measurement,and tested the control loop system and withstand voltage.The results show that,the temperature sensor operates well under 5kV,but the larger current will lead to damage the sensor;discharge will occur under high voltage between the shell of common conversion terminal and pin-linked temperature sensor,and will lead to sensor damage;thus,it is necessary to design a special terminal.Higher level insulation is required in designing 10kA HTS cable noumenal insulation,the floating potential design should meet the insulation needs of monitoring,and the control system needs to prevent occurring of partial discharge.The voltage withstand test carried on the 10kA HTS cable system after the integration shows that the insulation system meets operational requirements.