超导磁共振主磁体励磁测控系统设计与开发

医用超导磁共振主磁体在励磁过程中出现的交流损耗和传导漏热等情况,是超导磁体失超的根本原因；为了控制和保证励磁过程的稳定性、可靠性和安全性,开发和完善励磁的测控系统就显得格外重要；设计并开发了基于LabVIEW平台的超导磁共振主磁体励磁测控系统；系统数据通过在虚拟仪器平台上调用动态链接库文件(DLL),控制泰克公司KE2700系列集成式采集卡采集得到；传感器选择根据相应功能需要配置；操作台仪器控制、数据采集程序和人机界面由LabVIEW编写；搭配保护电路,保护超导线圈,降低失超损失；实现数据采集、参数控制、失超保护、匀场测试等功能。系统满足设计开发目的,平台搭建稳定可靠；功能相对完善,具体操作简易,交互界面友好,后期修改和功能扩展灵活；经工程实际运行测试验证,提高了研究和工作效率,达到设计要求,有实际应用价值。

Design and Development of a Magnetic Field Ramping Control and Measurement System for Superconducting MRI

AC loss and conduction heat leakage are the main cause of magnetic quench during magnetic field ramping for superconducting MRI systems. In order to maintain the stability and safety of field ramping process, it is important to have a well-designed field ramping control and measurement system. In this study, a field ramping control and measurement system was designed and developed using the LabVIEW platform. System data were acquired through using dynamic linked library, DLL-controlled Tektronix KE2700 system. The selection of transducers was based on required system functionality and specification. System control platform, data acquisition program and user interface (UI) was developed on workstation using LabVIEW with easy modification of acquisition parameters through UI. Quench protection resistance can protect the superconducting coil from loss of energy, and loss of superconductivity. System met the design requirement, and the established platform was stable and reliable, with relatively complete functionality. System is easy to operate, with user-friendly interface, and easy for future expansion and debugging. After detailed engineering test and practice, it was shown that the system design and application requirement can be met, and system design goals were achieved. With its improved efficiency, this study has great value in actual application for superconducting magnets.