An iterative procedure for equivalent source representation of focusing magnetic fields in TWT

Purpose – This paper aims to present a new iterative procedure for the 3D representation of focusing magnetic fields in TWTs generated by PPMs, by using equivalent sources and optimisation algorithms.Design/methodology/approach – In the integrated optimisation strategy general models for magnetic sources are employed and local and global inverse problems are iteratively solved for the minimization of the representation error.Findings – The results obtained show that the target accuracy is reached with a low computational effort, employing a minimum number of equivalent sources.Practical implications – The procedure is robust and converges for all the examined magnetic field configurations.Originality/value – Different from other approaches, the procedure presented here can be directly applied to a variety of different models for magnetic sources.