Page 138 - Modern Control of DC-Based Power Systems

102 Modern Control of DC-Based Power Systems

Figure 3.11 Pole positions as function of the value of the droop coefficients.

As an example Fig. 3.11 describes how the eigenvalues of this matrix
and then the eigenvalues of the system move by changing the value of the
droop coefficients. The following parameters have been used for the cal-
culation: (R 1 5 0:1Ω; R 2 5 0:2Ω; τ 1 5 0:2s; τ 2 5 0:3s;R d1 5 0:1 4 40Ω;
R d2 5 0:2 4 20ΩÞ.
Looking at the results, it is possible to see that the system always pre-
sents two real poles. While one pole moves in the direction of stability,
the second one moves closer and closer to the unstable region.

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