A.A. Shvachko1, A.A. Potapov2, Z.N. Jihad3

1-3 Yuri Gagarin State Technical University of Saratov, (Saratov, Russia)

When designing focusing systems, it is important that the effect of technological deviations in the geometric parameters of magnets on the magnetic field is minimal. This is necessary because of the effect of such a change on positioning in the stability zone. Technological deviations of geometric parameters occur directly in the process of manufacturing the system and are often not incorporated in the design. Ignorance of the effect of deviations in the parameters of the magnets that occur during the manufacture of the magnetic system affects the performance of the device and the number of defective products. Reducing the number of defective products is possible by taking into account and laying down the possible influence of technological deviations on the parameters of the entire device as a whole at the design stage. The purpose of the work is to create a methodology for assessing the impact of technological deviations on the parameters of the passage of an electron beam, as well as a computer program that allows you to automate the process of research.

The article presents a mathematical model for assessing the effect of technological deviations in the geometric parameters of permanent magnets on the parameters of a traveling wave tube. The technique is proposed to be carried out as follows: assessment of the influence of technological deviations of the geometric parameters of the permanent magnets of a periodic magnetic focusing system on the magnetic coefficient describing the electron beam pulsations, and assessment of the magnetic field sensitivity by the corresponding geometric parameter of the annular magnet. A computer program is presented that implements the described methodology for assessing the impact of technological deviations. As output data, the program generates the following graphical data: a graph of the change in the magnetic field from the thickness of the magnet, a graph of the change in the magnetic parameter from the thickness of the magnet, a graph of the change in the sensitivity of the magnetic field to changes in the thickness, inner and outer diameters of the annular magnet. The program can also generate a summary table with the following data: values of variable thickness, inner and outer diameters, magnetic field on the magnet axis, changes in the magnetic parameter with a corresponding change in geometric parameters, sensitivity of the magnetic field to changes in thickness, inner and outer diameters.

The described technique makes it possible to evaluate the effect of technological deviations in the geometric parameters of permanent magnets in a periodic magnetic focusing system on the parameters of the electron beam pulsation, as well as on its stability. The written program allows you to automate the process of research and evaluation of the influence of deviations in a traveling wave tube with a periodic magnetic focusing system.

Shvachko A.A., Potapov A.A., Jihad Z.N. Electron beam stability under the influence of technological deviations: software. Radiotekhnika. 2022. V. 86. № 12. P. 111−119. DOI: https://doi.org/10.18127/j00338486-202212-10 (In Russian)

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