Passive low-pass filters are widely used to prevent the spread of high-frequency noise within sensitive electronic systems. Usually, for specific applications, such filters have high performance and reliability requirements. However, harsh operating conditions can cause a significant reduction in filter performance. This paper presents an actual case of a filter failure and describes measurements and simulations to evaluate its performance. Measurements were made to evaluate the condition of the filter compared to the functional one. Numerical simulations, based on the measurements, were attempted to serve as a tool to identify the reason for the degradation. The described approach can be a promising tool for finding the discovery of a possible cause of degradation.

The new continuously emerging technologies, over the last years, increase the complexity of electromagnetic environments as more electronic devices are implemented in modern applications such as e.g., vehicles, aircrafts, etc. The already applied electromagnetic compatibility standards, however, struggle to keep up with these new age technologies and do not always account for characteristics met in real dynamic environments as required by the EMC directive. Therefore, potential harmful electromagnetic interference sources cannot always be identified and overcome. For detection of such threats, deeper investigation towards actual environments and existing cases is necessary. Risk-based EMC analysis can help distinguish critical cases in a common real electromagnetic environment as it deviates from the fixed standardized conditions. In this paper, a real case of a scooter, acting as a victim is represented via a simple model and macroscaled parameters to identify and determine significant induced values caused by a coupling of an unknown source. Experiments as well as simulations validate the macro-parameter concept of the applied case and allow to perform a simplified study of its behavior when exposed to a complex electromagnetic environment without the necessity to run expensive and lengthy measurements. Even though the expected precision of such a test is expected to be relatively low, it is sufficient to be incorporated in the macro-parameter-based model focused on rough-butusable EMI estimations within a complex environment rather than exact-but-wrong solutions obtained in a perfectly clean laboratory setup.