Energy analysis of an electromagnetic loudspeaker

Natasha Hirschfeldt, Roberta Lima, Rubens Sampaio


An electromechanical system is composed by two subsystems with distinct origins:  one of a mechanical nature and another of electromagnetic nature. The energies in the system  have also different origins. Some of them are mechanical, as kinetic and potential, and others  are electromagnetic, as magnetic and electrical. For a proper description of an electromechanical  system dynamics it is not sufficient to describe each subsystem separately. Coupling terms must be  considered in the system dynamics. These terms characterize the mutual influence between the two  subsystems and the interplay of the energies of the system. The objective of this paper is to analyze  from an energetic point of view an electromechanical system. This paper shows how the dynamics  of an electromechanical system can be constructed by the definition of the energies that are present  in the system and their interplay using the Lagrangian method. To exemplify, an electromagnetic  loudspeaker will be analyzed. Its dynamics will be constructed and numerical integrated in order  to make an energetic analysis.  


Lagrangian; energy; co-energy; electromechanical; transducer.

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