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Many physical systems contain elements with distributed and lumped parameters; this paper proposes modeling these systems using a bond graph approach. A junction structure is proposed in which the relationships between the distributed and lumped parameter elements are indicated; from this structure, the state space mathematical model of the system is obtained. Thus, a symmetry between the graphical model and the mathematical model is determined. Traditionally, the distributed parameters in the bond graph approach have been modeled by fields. However, when these fields may be subject to external disturbances or parametric uncertainties, their analysis is complicated to carry out because all the information is in a compact form. Therefore, this paper presents a methodology for changing a field in an element model; these fields can be storage fields in an integral or derivative causality assignment or dissipation fields in both cases for any number of field ports. Likewise, there is another symmetry in bond graph from a model with fields to a model with elements. As a case study, a wind turbine containing fields and elements in bond graph is modeled. The state space mathematical model of the turbine is obtained from the bond graph structure of the model with fields in bond graph. Another model of the turbine in bond graph with elements only, applying the field decomposition procedure to elements, is presented. Thus, an external disturbance is introduced into the turbine model with elements showing the objective of obtaining this symmetrical model of the turbine. Simulation results of bond graphs with fields and elements are obtained by checking the symmetry of the models. Likewise, the behavior under conditions of an external disturbance applied to the turbine is presented.