Coupling Losses Characteristics of Large Superconducting Conductors for Electric Power Applications Affected by Internal Transverse Electromagnetic-Forces

绞合导线的股间耦合损耗可以根据其应用情况而变得更大。这是一个需要考虑的问题。至于这些损失，最近进行了许多调查。但对于其中的大多数，估计了在变化的横向磁场下的损耗。根据他们的说法，损耗在很大程度上取决于表面条件和绞合电缆的结构。在实际应用的情况下，导体通常有传输电流，因此导体中的线束受到电磁力的作用。损失可以通过力量来改变。但这些损耗的变化特征还不清楚。本研究的目的是开发一种系统，能够在横向磁场作用下测量所有有传输电流的绞合导线的股间耦合损耗，并在较宽的频率范围内测量这些损耗，并阐明这些损耗与对绞线的电磁力的关系。这一新的测量系统使我们能够在0.1-300赫兹的波纹场的宽频率范围内测量传输电流为20-30kA、横向磁场为3.22T的大型导体的耦合损耗。利用该系统测得偏置横向磁场下的耦合损耗为1.5T，传输电流下的耦合损耗为20kA。测量数据表明，对于大型螺旋器件极向场线圈(LHD)的IS导体，耦合损耗在电磁力为0.9 Mpa的低频范围内变化很小。

The inter-strand coupling losses of stranded conductors can become larger according to circumstances of their applications. It is a problem to be considered. As for those losses many investigations have been made recently. But for the most of them the losses under the changing transverse magnetic field are estimated. According to them, the losses much depend upon the surface conditions and the structures of the stranded-cables. Under the circumstances of their real applications, the conductors usually have transport current, and consequently the strands in the conductors are subjected to the electromagnetic-forces. The losses can be changed by the forces. But the characteristic of these changes in the losses is not yet made clear.The purpose of this study is to develop the system which can measure the inter-strand coupling losses itself in the stranded conductors above all cable-in-conduit (CIC) conductors with transport current under the transverse magnetic field, and that in a wide frequency range, and to elucidate the dependence of these losses on the electromagnetic-force to the strands. This new measuring system enables us to measure the coupling loss of large scale conductors with transport current of 20-30kA and the transverse magnetic field of 3.22T bias in the wide frequency range of the superposed ripple field of 0.1-300Hz. By this system the coupling losses are measured to the extent of 1.5T in the bias transverse magnetic field, and 20kA in the transport current. The data of the measurements show that the change of the coupling loss is only a little in the low frequency range to the extent of the electromagnetic-force of 0.9MPa in the case of IS-conductor of the poloidal field coil for Large Helical Device (LHD).