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This paper addresses and compares the modeling of typical EMI filters used in three-phase power equipment obtained through two different approaches, namely, physical and behavioral. Firstly, an innovative physical EMI filter modeling procedure is presented, which relies on an analytical formulation in terms of chain-parameters matrices and allows for an easy evaluation of its attenuation characteristics. The considered procedure builds an overall filter model by combining simple components models, requiring the determination of only a limited number of parasitic elements. Furthermore, the latter can be easily estimated without the need to build any prototype, avoiding the costly trial-and-error design procedures currently applied in the industrial context. Additionally, the considered physical model is tailored for high-power filters, built with thick wires, while most of the physical models available in the literature are aimed at small-sized filters built on printed circuit boards. The procedure is validated step by step, discussing the accuracy of each component model and its impact on overall accuracy compared to the actual measurements of the final assembled filter. Secondly, a behavioral modeling procedure is presented, which is based on external measurements performed on the filter prototype and provides an equivalent circuit model. Specifically, it extends to three-phase filters a circuit model previously developed for the single-phase case. Lastly, a critical comparison between the proposed physical and behavioral models is presented, highlighting the strengths and limitations of both and suggesting optimal uses for each. [ABSTRACT FROM AUTHOR]

Automation in the manufacturing of electronic products and devices has been increasingly implemented in the last decades, to cope with the growing demand for mass emerging products. However, some niches still exhibit a large room for improvement. Considering flexible electronics production, this work addresses the assembly of film coverlays, which is still conducted manually, mainly due to the technological challenges related to the manipulation of film-based components and the removal of the film protecting the adhesive layer, along with the extreme variability of their shape and dimension. These issues result in stressful and troublesome tasks for the operator, besides preventing the full digitalization of the production process. A multifunctional gripper is presented as the core device to enable assembly automation. The study concerns the full gripper development, from the analysis of requirements and concept definition to design, prototyping and testing. The device was tested installed on a robot arm, demonstrating full reliability for the completion of all assembly process tasks. Moreover, the assessment of positioning performance confirms the fulfilment of process requirements, still providing insights for slight improvements. The gripper represents a scalable solution for the automated assembly of film-based coverlays, ready for validation in industrial settings. [ABSTRACT FROM AUTHOR]

DC smart grids are a promising solution for the efficient integration of renewable energy sources and loads. Still, their widespread adoption is hindered by significant challenges related to fault response, identification, and clearance. The traditional DC fault analysis method is a useful tool for straightforwardly understanding the behaviour of fault current contributions from DC converters in LVDC networks during a fault. However, when a system with multiple converters and non-negligible fault impedance need to be considered, its accuracy is severely limited due to the assumptions included in the problem solution, thus leading to the following: (a) the dependency of the results' reliability on fault impedance values and/or other converter fault current contributions; (b) the inaccuracy of the diode current estimation; and (c) the inaccuracy of the conductor joule integral. Thus, these results' data may be unreliable for designing protection systems for one converter or for an entire network. In order to overcome these issues, this paper proposes an innovative, simple numerical approach to DC fault current evaluation, which can be adopted when the number of converters become significant, or the network is complex. This method arises from the primary interest in solving the circuit to extract the indicators (current peak value and time, joule integral, etc.) necessary for designing circuit protections. This approach proved to grant two main advantages over traditional methods: (a) it provides accurate results, with no need to introduce any specific assumption; (b) it can be structured to manage an arbitrary number of converters; and (c) it reduces the computational processing times and resources necessary to simulate an entire DC network in comparison to other circuit solution software. [ABSTRACT FROM AUTHOR]