Editor's note: This product how-to describes how to use Synopsys' Saber platform for modeling and simulating physical systems and CST Studio Suite electromagnetic simulation software. Synopsys and CST recently launched a technology partnership to build a high-quality interface between Saber and CST Studio Suite. This article originally appeared in Elektronik automotive 12/2012, WEKA FACHMEDIEN GmbH.
Thomas Edison would be happy, but for automotive product development groups, the increasing electrification of automotive platforms presents all sorts of new EMC validation challenges. Driven by the growing number of electrical functions such as drive systems for hybrid vehicles or pure electrical drives, driver assistance systems, and advancements in consumer electronics, electrification of automotive platforms means teams have to validate each systems for electromagnetic compatibility (EMC) across the complete operating range to ensure full compliance with the required quality and safety criteria. In particular the noise emission of dedicated components or embedded control units (ECU) may adversely impact the vehicle's network or other components.
EMC specifications determined by EU framework directive 2007/46/EC or according to rule ECE-R10 require careful verification.1, 2 Verification tests span frequency ranges up to 2GHz or higher. To complicate matters, vehicle manufacturers often impose additional EMC constraints on the system designs. Identifying and resolving design malfunctions caused by EMC issues can consume significant resources and add cost intensive design iterations. Often, ECU implementation-specific problems are encountered that require answers to the following questions. Whether a lead frame has to be used or an ordinary circuit board? Which HF filter types are being deployed? What about the control unit construction and the positioning of the components within the ECU? Should the emission be analysed as narrowband or broadband?
In extreme cases, it may be necessary to change the physical design, the ECU architecture, or filter elements. Implementing these changes may be costly and require additional development time adding risk to platforms that are otherwise ready for production. Substantial changes may even delay the product launch. In order to minimize the risk associated with these issues, early detection is crucial. To achieve this goal, designers are employing simulation tools to develop virtual solutions. Simulation-based methodologies enable engineers to perform EMC analyses of the control unit early in the development process, even before the ECU is available for EMC testing.3
Typically, applying the EMC tests to automotive ECUs in actual hardware is time consuming. In addition, it's difficult to precisely reproduce the exact measurement conditions such as temperature or device parameter drift. Owing to the persistent miniaturization of automotive electronic components, direct measurements might not even be possible to perform. In such scenarios, simulation presents the only path to validate EMC performance.