Strict EMC requirements for an automotive electronic component force designers to solve EMC issues as early in the design phase as possible, preferably in the concept phase. EMC solutions also need to be optimized, in order to achieve best cost to design electronic component. EMC measurements are performed on electronic component prototypes to check EMC performance of a design. Thesis presents simulation models and algorithms that enable designers to estimate electromagnetic radiated emissions of an automotive electronic component virtual concept. Analyses of electromagnetic radiated emissions and quicker solutions seeking to reduce the emission levels are also possible with presented simulation models.
The model to estimate electromagnetic radiated emissions from an automotive electronic component’s cable harness was built based on a test setup used in measurements. The model requires cable harness common-mode current distribution in frequency domain. The common-mode current is calculated with the model to estimate amplitude and phase of common-mode current on a cable harness of an electronic component. The model calculates amplitude and phase of common-mode current by using simulation results from electromagnetic radiated emissions system simulation in time or frequency domain. Simulation include simulated real parts of electronic device e.g. printed circuit board, connectors, integrated circuit, cable harness, load simulators etc. Thesis is focused on automotive electronic components, where source of emissions originate from a digital part of integrated circuit. In order to be able to transform the results simulated in time domain to frequency domain, we have also built an EMI receiver model. The model takes into consideration the properties of EMI receiver used in emission measurements. We have upgraded the EMI receiver model to also calculate the phase spectrum of the emissions.
Both models, model to estimate amplitude and phase of common-mode current on a cable harness and model to estimate electromagnetic radiated emissions from an automotive electronic component’s cable harness, were verified in two EMC laboratories accredited according to standard ISO/IEC 17025. We have compared the results obtained in both laboratories with results from simulations.
In the last part of the thesis we present step-by-step modelling of electromagnetic radiated emissions on test electronic component intended for sensor applications in automotive industry. Electronic component uses CMOS integrated circuit, which is the major source of electromagnetic emissions. We have designed two versions of integrated circuit with synchronous digital parts. REF version of IC, where all gates switch simultaneously and SCT version of IC, where gate switching is distributed evenly in one clock period. We have built simulation models in time and frequency domain to simulate conducted emissions of integrated circuits. Simulation results were compared with the measurements. We have also built simulation models in time and frequency domain to simulate radiated emissions from automotive electronic component with integrated circuit. We have compared simulation results with measurements. Deviation between simulations and measurements were discussed.
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