Page 198 - Hybrid-Renewable Energy Systems in Microgrids

178 Hybrid-Renewable Energy Systems in Microgrids

Figure 9.8 Variation of imaginary part of the mechanical mode with respect to the
generator inertia.

Figure 9.9 Imaginary part of the electromechanical mode with respect to turbine inertia
with and without SDBR.

Change of turbine inertia, while keeping all other parameters constant, does not
cause significant variation for the electrical mode with or without SDBR as it is a
mechanical parameter as the generator inertia.

2.4.2 Generator parameters
To investigate the sensitivity analysis with respect to the generator parameters two
parameters are considered (Fig. 9.10).
Stator Resistance: The sensitivity of electrical mode with respect to the stator resis-
tance is the following:

∂ λ ∂ λ ∂ a ∂ λ ∂ a ∂ λ ∂ a
1 = 1 . 6,6 + 1 . 6,5 + 1 . 4,4
∂ R ∂ a ∂ R ∂ a ∂ R ∂ a ∂ R
ts 6,6 s 6,5 s 4,4 s
∂ λ ∂ a ∂ λ ∂ a ∂ λ ∂ a
∂λ ∂Rts=∂λ ∂a6,6.∂a6,6∂Rs+ + 1 . 4,7 + 1 . 5,6 + 1 . 7,4 (9.35)
1
1
∂λ ∂a6,5.∂a6,5∂Rs+∂λ ∂a4,4. ∂ a 4,7 ∂ R s ∂ a 5,6 ∂ R s ∂ a 7,4 ∂ R s
1
1
∂a4,4∂Rs+∂λ ∂a4,7.∂a4,7∂Rs
1
+∂λ ∂a5,6.∂a5,6∂Rs+∂λ ∂a7,
1
1
4.∂a7,4∂Rs