Electrification plays an important role in the transformation of the mobility industry and offers great opportunities in all vehicle segments. In order to ensure a fast and broad acceptance of electric mobility, the rapid market introduction of new e-vehicles is an important process. From an EMC point of view, the integration of electric drive systems in today's automobiles is a major challenge. The electric drive system consists of a high-voltage power source, a frequency converter, an electric motor and shielded or unshielded high-power cables.

Because of the limit values to be met, the EMC challenges in the development of electric drive systems are high and so the measures to comply with the requirements are also diverse.

One of the measures often used is the application of cable sleeves made from ferrite or nanocrystalline. These are rings or sleeves made of a material that has special magnetic properties. If such a sleeve is placed over a cable, the radiation of high-frequency energy ("EMC interference") from the cable can be reduced. In order to be successful with such simple EMC measures, certain prerequisites must be observed, which are shown and explained in this application note. The brief theoretical explanation of the functional principle and the most important influencing parameters is supplemented by practical measurements.

Content:

• Technical background of EMC in automotive
• Important parameters for sleeve application
• Measurement results
• Measurement setup according to CISPR 25 and influencing variables
• Cable as antenna
• Recommendations for specific measures

Download: ANP115