Parametrization of electromechanical systems must acknowledge Newton and Maxwell
DOI:
https://doi.org/10.5540/03.2021.008.01.0459Palavras-chave:
Lagrangian, Energy, Co-energy, Electromechanical system, Galvanometer.Resumo
Electromechanical systems are an interesting type of coupled systems. They are com- posed by two subsystems with different nature: mechanical and electromagnetic. The subsystems interact. To represent the dynamics of a coupled system, it is necessary to properly characterize their interaction. The dynamics of an electromechanical system is given by an initial value prob- lem (IVP) comprising a set of coupled differential equations involving, necessarily, mechanical and electromagnetic variables. Despite the ubiquity of electromechanical systems, a few authors do not parametrize them properly. Frequently, by some artífice, strange to the problem, the coupled system is uncoupled disregarding the electromagnetic subsystem. Hence, the uncoupled system has a different dynamics, resulting a reduced IVP with only a mechanical equation. This paper discusses this uncoupling using as example a galvanometer, a well-known measuring device. To analyze the effects of the decoupling, numerical simulations of the two IVP, complete and reduced, are performed.
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