Study of High Stable Magnetic Field by Superconducting Transformer

超导变压器高稳定磁场研究

基本信息

批准号：
16560245
负责人：
OTABE Soji
金额：
$ 1.28万
依托单位：
Kyushu Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16560245/
关键词：
Superconducting Transformer DC mode Coupling Coefficient Time Constant

项目摘要

In 2004, DC transport current was tried to be induced by 500A class superconducting transformer. However, since the superconducting transformer was design to obtain high current, it was difficult to hold DC current for long time. In 2005, a new superconducting transformer was designed and fabricated in order to hold DC current for long time even though the magnitude of the current was small. The transport current induce in secondary winding was measured by the voltage at the low resistive shunt resistor inserted in the secondary winding. The current at the first winding of the superconducting transformer was controlled by PID method. For the result, the controlled time was extended to about 1 second. The control accuracy was within plus minus 0.4%. This value is far from 1 ppm which is required by NMR and MRI.In 2006, the accurate of current was tried to be improved by the knowledge obtained in previous studies. It is necessary to correctly measure the current induced in the secondary winding in order to obtain the stable current. Therefore, the magnetic field induced in the secondary windings was measured by a hole sensor and a pickup coil. The current of the first windings was controlled by the measured current of the secondary windings. As the result, the pickup method was better than the hole sensor method, and the more accurate control was established.In summary, the DC mode of the current induced in the secondary winding of the superconducting transformer is performed and confirmed. The methods to obtain stabilized magnetic field and current were proposed and performed. It is considered that these methods will be applied to many kinds of superconducting apparatuses. For example, the present knowledge will be applied to NMR and MRI facilities to obtain high stability magnetic field.

2004年，DC传输电流被500A类超导变压器诱导。但是，由于超导变压器的设计是为了获得高电流，因此很难长期保持直流电流。在2005年，设计和制造了一种新的超导变压器，以使直流电流长时间保持，即使电流的幅度很小。通过在二次绕组中插入的低电阻分流电阻器处的电压来测量次级绕组中的转运电流。超导变压器第一次绕组处的电流由PID方法控制。为了结果，受控时间扩展到大约1秒钟。控制精度在加上减去0.4％之内。该值远非NMR和MRI所要求的1 ppm。为了获得稳定电流，有必要正确测量次级绕组中引起的电流。因此，通过孔传感器和拾音器线圈测量了次级绕组中诱导的磁场。第一绕组的电流由次级绕组的测量电流控制。结果，拾取方法比孔传感器方法更好，并建立了更准确的控制。总而言之，在超导变压器的次级绕组中诱导的电流的直流模式进行了执行并确认。提出并执行获得稳定磁场和电流的方法。据认为，这些方法将应用于多种超导设备。例如，目前的知识将应用于NMR和MRI设施以获得高稳定性磁场。