SYSTEM ANALYSIS THROUGH BOND GRAPH MODELING by ...

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Figure 3.2 shows a zero and a 1-junction and the implied meanings of the effort and
flow variables. The 0-junction of figure 3.2 shows five power bonds connected to the
junction, and the 1-junction of figure 3.2 shows three power bonds connected to the
junction to indicate that each junction may have an unlimited number of power bond
connections. The power bonds, on each of the junctions in figures 3.2, are arbitrarily
numbered to keep track of the conjugate variables associated with them.
It is clear from figure 3.2 that each type of junction conserves power in that power
into the junction is equal to the power out of the junction. By holding one of the
conjugate variables equal on all bonds connected to the junction, the other conjugate
variable must then sum to zero, i.e., incoming minus outgoing equals zero.
3.2.3 1-Port Elements
Bond graphs use five types of idealized 1-port elements. Two of these elements are
active and the remaining three are passive. The two active 1-port elements are the
idealized bond graph sources, consisting of an effort source and a flow source. Each of
these elements is shown in figure 3.3. Bond graph sinks are represented by reversing the
direction of the power arrow opposite that shown in figure 3.3.
Bond graphs use three types of idealized passive 1-port elements. Two of these
elements are energy storage elements and the other is a dissipative element. Each of
these elements exchanges power from one form to another in their own unique way.
These elements are considered to be passive, since they do not contain any sources of