基于虚拟仪器技术的工频X线机单元电路实验系统的设计

为了提高工频X线机电路实验教学的开放性和解决实验设备费用高、易损坏、更新慢等问题，研究并开发一套教学使用的工频X线机单元电路实验仿真系统，可以完成工频X线机电路实验课程的基本教学任务。结合工频X线机电路实验教学课程的需求，以工频X线机典型的单元电路为例，采用电路仿真软件Multisim仿真实验电路，虚拟仪器开发软件LabVIEW进行实验系统界面设计，并利用接口技术实现二者之间的通信联结，完成工频X线机单元电路实验系统的构建。设计完成后的实验系统能够仿真实际X线机单元电路的工作过程，学生可以在理论学习的基础上，利用此套系统进行X线机整流电路、限时电路、空间电荷补偿电路、容量保护电路、旋转阳极启动、延时及保护电路的实验。测试结果表明，该实验系统可以完成工频X线机单元电路实验课程中的电路参数测量、电路信号测试及参数显示任务，通过与真实单元电路实验箱的对比，证明了实验结果可以反映出真实的X线机球管电气特性。该实验系统有效地增加了学生的动手实践机会，可扩展性强，有利于探究性电路实验的进行，因此，将虚拟仪器技术用于设计和实现工频X线机单元电路实验系统是一种非常有效的方式，既解决了实验设备不足的问题，也为其他医学影像设备电路实验仪器的设计和研制提供新的思路。

Designing elemental circuit experimental system of power frequency X-ray machine based on virtual instrument technology

In order to improve the openness of the experimental teaching of power frequency X-ray machine circuit, and to solve the problems of high cost, easy damage and slow update of experimental equipment, research and development of a set of power frequency X-ray machine elemental circuit experiment simulation system for teaching, it can be completed the basic teaching tasks of the power frequency X-ray machine circuit experiment course. Combined with the requirements of the experimental teaching course of the power frequency X-ray machine circuit, taking the typical elemental circuit of the power frequency X-ray machine as an example, the circuit simulation software Multisim simulation experiment circuit, the virtual instrument development software LabVIEW is used to design the experimental system interface, and the interface technology is utilized. The communication connection between the two is realized, and the construction of the experimental system of the power frequency X-ray machine elemental circuit is completed. After the design is completed, the experimental system can simulate the working process of the actual X-ray machine elemental circuit. Students can use this system to carry out X-ray machine rectifier circuit, time-limited circuit, space charge compensation circuit and capacity protection circuit on the basis of theoretical study. Experiments with rotating anode start-up, delay, and protection circuits. The test results show that the experimental system can complete the circuit parameter measurement, circuit signal test and parameter display task in the power frequency X-ray machine unit circuit experiment course. By comparing with the real elemental circuit experiment box, it is proved that the experimental results can reflect the actual X-ray machine tube electrical characteristics. The experimental system effectively increases the hands-on practice opportunities of students, and is highly scalable, which is conducive to the exploratory circuit experiment. Therefore, the virtual instrument technology is used to design and implement the power frequency X-ray machine elemental circuit experiment system. A very effective way not only solves the problem of insufficient experimental equipment, but also provides a new idea for the design and development of other medical imaging equipment circuit experimental instruments.