Analysis of radiated emission due to the wire-wound type power inductor in high voltage DC to DC converter

Nowadays, the parts of eco-friendly vehicles such as hybrid and electric car are being developed very quickly. In particular, braking and steering system for the eco-friendly vehicles are being more important. This is because existing internal combustion engines require engine power for braking and steering, but eco-friendly cars do not have engines or are not in constant operation. Therefore, actuators and electronic controllers that enable braking and steering without an engine are used. However, electronic controllers for controlling actuators cause many EMC problems. In this paper, the radiated noise generated from the DC-DC converter that converts the vehicle 12V battery within the ECU, an electronic control system, was analyzed through 3D EM analysis. In the process of switching the vehicle battery voltage, the DC-DC converter generates a large amount of EMI noise, which causes problems such as reduced sensitivity of the vehicle's radio reception. In this paper, a 3D analysis model was established for the switching noise radiation of a DC-DC converter according to the mounting conditions of a high-voltage wire-wound type power inductor, and a design method for reducing radiation noise was presented through this.