超导直流电缆的短路冲击特性分析

Research on electric-thermal characteristics of superconducting cable under short-circuit impact test

柔性直流输电应用场景逐渐丰富,超导直流输电作为一种新型输电技术,具有零电阻的优势,但直流网侧短路故障对超导电缆的冲击效应有待进一步研究。研究了Bi2223超导带材及其绕制的电缆短样在直流冲击作用下电阻、电压随电流的变化规律,总结出试样的短路冲击特性,并针对Bi2223带材与电缆的特性差异进行理论分析,得出电缆铜骨架结构能有效抑制直流冲击下的焦耳热生成,为超导直流电缆的优化设计和故障分析提供了理论依据。

The application scenarios of VSC-HVDC transmission are becoming more and more abundant. As a new type of power transmission technology, superconducting DC power transmission has an advantage of zero resistance, while the impact effect of grid short-circuit fault on superconducting cable in DC power system is pending further research. This paper studied the resistance and voltage changing of superconducting Bi2223 tape and its winding cable sample under the effect of DC impact and exposed the sample’s characteristics under short-circuit impact. Based on the theoretical analysis of the difference between the characteristics of Bi2223 tape and cable sample, it is concluded that the cable copper former can effectively inhibit the Joule heat generation under DC impact,providing a theoretical reference for the optimal design and fault analysis of the superconducting DC cable.