Use of a priori geometric information to improve the identification of the B-field measurement around a power electronic device
Résumé
Electromagnetic interference between power electronic systems often causes malfunctions. This problem of electromagnetic compatibility (EMC) has become an essential issue for their design. This work focuses on the near-field inductive coupling between two systems. In order to take it into account during the industrial design phase, a predictive method was proposed, based on the multipole expansion in spherical harmonics of the magnetic induction field measured around each system. The accuracy of the characterization depends on several factors such as the number of measurements, the position of the measuring points, the sensitivity of the measuring instruments, and so on. In addition to the measurements, a priori information on the device is often available, allowing us to improve the accuracy of the identification. In this work, the properties of the expansion in spherical harmonics are linked to the a priori information (particularly geometric) and it is shown how this information can be used to improve the identification problem. In practice, the a priori information is often accompanied by some bias, which also needs to be considered. The methods will be illustrated by a few examples, such as a smoothing inductance.