Hyundai Mobis Leverages Feko for Enhanced EMC Analysis and Shielding Effectiveness Simulation

Hyundai MOBIS is a key affiliate of Hyundai Motor Group, specializing in the production of core automotive components. The company's extensive product range includes modules (chassis, cockpit, front-end-modules) and numerous automotive parts designed for customer convenience and safety. While Hyundai and Kia companies are the primary recipients of Hyundai MOBIS's modules, the company is also expanding its business to other auto manufacturers globally. Hyundai MOBIS is committed to developing new ultra-light materials to meet requirements for better fuel efficiency, performance, product appeal, reliability, and sustainability.

Hyundai MOBIS, a leading producer of core automotive components, was facing challenges in improving the efficiency and reducing the time taken in the electromagnetic compatibility (EMC) analysis process. The company uses shielding enclosures to protect against external fields and electromagnetic (EM) leakage from electronic products. However, the integrity of these enclosures was often compromised by apertures and slots used for visibility, ventilation, or access to interior components. These openings allowed exterior electric and magnetic fields to penetrate into the interior space, where they could couple to Printed Circuit Boards (PCBs), inducing currents and voltages on interior conductors. Therefore, it was crucial for Hyundai MOBIS to understand the EM shielding effectiveness of shielding enclosures in the presence of these apertures.

Hyundai MOBIS adopted a comprehensive approach to address the problem, analyzing it from a PCB level to a system level, including the shielding effectiveness for the current design of the Around View Monitor (AVM) housing. At the PCB level, simulations related to signal and power integrity were conducted once the AVM PCB design was available. The analysis of resonances, impedances, characteristic impedances, simultaneous switching noise, and DC IR drops helped identify power issues. Solutions were adopted to fix these issues to meet the required standards and regulations. Some of the solutions involved changing the value of capacitors or altering the structures of the ground planes to reduce loop inductances. A system level analysis was also carried out using FEKO® to analyze the effect of the material of the AVM housing on its shielding effectiveness. The workflow involved importing the near fields around the board into FEKO, creating an equivalent source for the PCB, and performing a 3D analysis and simulation of the shielding factor of the housing used for the AVM.

• The use of FEKO enabled Hyundai MOBIS to simulate the surface currents of the assembly consisting of equivalent source and AVM housing at several frequencies from 0.4 GHz to 4 GHz. This analysis provided a better understanding of the hotspots on the enclosure. Areas around the slots and the central mounting holes had higher current densities. By adjusting the width of the slots and connectors, these hotspots were reduced or even eliminated. Furthermore, the company was able to analyze the effect of each material on the shielding effectiveness and select the material providing the desired shielding factor against frequency. This comprehensive approach has significantly improved the EMC analysis process from 2D to 3D, enhancing the overall efficiency and effectiveness of the process.

• Hyundai MOBIS was able to save 33% of the simulation time by adopting a system level approach based on model decomposition and 3D analysis in FEKO.
• The company was able to maintain the accuracy of the simulation despite the reduction in time.
• The use of FEKO allowed Hyundai MOBIS to select the best composite material in terms of shielding effectiveness.