Cable Concept Selection for 600V Hybrid Heavy Duty Vehicle from an EMC Perspective

Abstract

It is important to minimize the emissions of electromagnetic fields to assure that the electrical equipment work properly. This thesis examines how to minimize electromagnetic fields with different cable types and placing of the cables. The cables are intended to be used in a hybrid heavy duty vehicle, for 600 V DC. Three different cable types was examined, one unshielded type, one shielded type and one type with two conductors with a common shield. The emissions of electric field from the cables were measured separately from the magnetic field emissions. The results of the measurements show that the electric field emissions are minimized by a shielded cable. The unshielded cables have a difference of 8 dBμV to the shielded cables at 0.15 MHz, and at 0.60 MHz is the difference increased to 18 dBμV. The magnetic field emissions are not affected by the cable type it is only affected by the placing of the cables. At 10 A is the magnetic field 28 μT when the cables are placed with 5 cm between them. When the cables have no distance between them the magnetic field is cancelled. Both the electric field and the magnetic field are minimized by a placing of the cables with no distance between them. If the cables are placed next to a grounded girder the electric field emissions is lowered with about 5 dBμV. If the girder is made of a material which conducts magnetic flux the magnetic field emissions is increased. The girder prevents the electromagnetic field to spread in four directions; it limits the emissions to three dimensions.