Optimizing power converter PCB design for lower EMI

Abstract

Purpose

The purpose of this paper is to develop a novel technique for the pre-design of a printed circuit board (PCB) of a DC-DC power converters where the placement of electric components can cancel the electromagnetic emissions through subtractive coupling and in this sense to minimize the stray magnetic and electric fields at a specific location. For this work the location of interest is a current transducer used for control purposes positioned in the center of a DC-DC Cuk converter board as a constrain.

Design/methodology/approach

The methodology of design is based on the development of an interface software platform through MatLab script coding which interconnects the solution of a numerical analysis software and an optimization technique. The numerical analysis software is based on finite element calculations where quasi-static field analysis are performed to calculate the radiated electric and magnetic fields. The optimization technique is conducted by genetic algorithms (GAs).

Findings

The results for the proposed procedure for PCB design show a significant reduction in radiated electromagnetic (EM) field at the susceptible device in the PCB. Even when the optimization procedure is applied only for the sensor center, the field reduction is extended for a wide region around the sensor. The proposed technique not only reduces the fundamental field component but also all the harmonic contents for the electromagnetic field. It is demonstrated that it is possible to cancel the emissions by means of varying the location and orientation of the passive elements avoiding the utilization of electromagnetic interference filters and complex modulations.

Originality/value

The novelty of the design procedure falls in the fitness function programming where an interface software platform is built through MatLab scripting to connect a 3D-FE analysis and the GA. The finite element analysis address the radiated EM calculation while the GA focus in the minimization of it. This computational platform has the flexibility to be easily adapted for the PCB design of any power electronic converter where the radiated EM compliance is required as well as extended to perform emissions minimization outside or/and inside the PCB.

Citation

Berzoy, A., Mohamed, A.A.S. and Mohammed, O. (2015), "Optimizing power converter PCB design for lower EMI", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 34 No. 5, pp. 1364-1380. https://doi.org/10.1108/COMPEL-02-2015-0082