# EMI reduction method of CISPR 36 pre-compliance testing using affordable rubber-based materials

## TL;DR

This paper introduces a cost-effective method using rubber-based materials to reduce electromagnetic interference in electric vehicles during pre-compliance testing.

## Contribution

The novelty lies in using affordable rubber-based materials for EMI shielding in electric vehicle modules during pre-compliance testing under CISPR 36 standards.

## Key findings

- Rubber-based materials reduced EMI emissions with shielding effectiveness between 37.362 dB and 37.742 dB for single layers.
- Combining two layers of materials achieved shielding effectiveness between 74.874 dB and 75.479 dB.
- The method is effective across several frequency ranges, particularly those regulated by CISPR 36.

## Abstract

Electric motor performance is greatly affected by emissions from the automotive drive system (drivetrain), necessitating research to mitigate electromagnetic interference (EMI). This study proposes a set of methods that employs simple and inexpensive rubber-based materials as shielding to reduce EMI in electric vehicle modules and further explores suitable materials to reduce emissions. The effectiveness of three different rubber compositions as shielding EMI, focusing on the frequency ranges regulated in the CISPR 36 standard, is investigated as pre-compliance testing in radial and transversal orientations of the measurement antenna. The study shows that using these methods together, the rubber-based materials under test can reduce EMI emissions by shielding effectiveness (SE) from 37.742 dB to 37.362 dB for single layer and 74.874 dB to 75.479 dB for combination of 2 layers with up to 50 % probability across several frequency ranges, especially the frequencies regulated in the CISPR 36 standard.

A realistic method to provide a reasonably cost-effective solution to reduce EMI, particularly for electric cars in the pre-compliance stage, using simple and inexpensive materials, mainly rubber-based materials,

EMI mitigation method using organic material as an absorber for pre-compliance testing in the frequency range of the CISPR 36 standard,

Method to determine the best combination of materials to reduce the emissions that arise from the electrical module of the DUT.

Image, graphical abstract