An Improved Analysis of PPM Focusing Structures Including the Effect of Magnetic Saturation in the Iron Pole Pieces

Author

Santra, Mrityunjay ; Kumar, Lalit ; Balakrishnan, Jyothi

Author_Institution

Defence Res. & Dev. Organ., Microwave Tube Res. & Dev. Centre, Bangalore

Volume

56

Issue

5

fYear

2009

fDate

5/1/2009 12:00:00 AM

Firstpage

974

Lastpage

980

Abstract

In this paper, an improved analysis of the periodic permanent magnet (PPM) focusing structure for linear beam tubes is presented. An estimation of critical dimensions for the iron pole pieces to avoid magnetic saturation is made. The method is based on the permeance calculation of all possible flux paths using magnetic circuit theory. The analytically calculated axial magnetic field using the present approach is compared with measured and simulated results obtained by using the finite-element-method-based commercial software ANSYS. The agreement is very good.

Keywords

finite element analysis; magnetic circuits; microwave tubes; permanent magnets; ANSYS; PPM focusing structure; axial magnetic field; critical dimensions; finite element method; flux path; iron pole pieces; linear beam tube; magnetic circuit theory; magnetic saturation; periodic permanent magnet; permeance calculation; Analytical models; Iron; Magnetic analysis; Magnetic circuits; Magnetic field measurement; Magnetic flux; Periodic structures; Permanent magnets; Saturation magnetization; Software measurement; Focusing; magnetic circuits; permanent magnets; traveling-wave tubes (TWTs);

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/TED.2009.2015805

Filename

4804772