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随应用场合的不同而增大。这是一个需要考虑的问题。关于这些损失，最近进行了许多调查。但对于大多数的损失下的变化的横向磁场进行了估计。根据他们的说法，损耗很大程度上取决于表面条件和绞合电缆的结构。在其真实的应用环境中，导体通常具有传输电流，因此导体中的股线受到电磁力的作用。力可以改变损失。本研究的目的是研制一套能够测量横向磁场作用下有传输电流的绞合导线（包括所有CIC导线）的股间耦合损耗的测量系统，并在较宽的频率范围内，并阐明了这些损耗对绞线电磁力的依赖性。这种新的测量系统使我们能够在0.1- 300 Hz的叠加涟漪场的宽频率范围内测量传输电流为20- 30 kA、横向磁场为3.22T偏置的大尺寸导体的耦合损耗。在偏置横向磁场下测量到1.5T的耦合损耗，在输运电流下测量到20 kA的耦合损耗。测量结果表明，在电磁力为0.9MPa的范围内，大螺旋装置极向场线圈采用IS导体时，低频范围内耦合损耗的变化很小。

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).