Page 290 - Mathematical Models and Algorithms for Power System Optimization

282 Chapter 7

Seen from this example, the latter method is much simpler than the former one. When
determining coefficient b, it is not required to do a lot of work to combine the similar terms,
only applying Eq. (7.121). As a result, the latter method is adopted as worthy.

7.9 Conclusion

The study in this chapter establishes an accurate model of the load disturbance, improves the
estimation and forecast accuracy of the load disturbance, and provides a reliable basis for
designing the new load frequency controller. The hierarchical estimators are utilized not only to
minimize the estimated amount of calculations but also to create conditions for centralized and
decentralized coordinated control of large-scale power systems. The compensation controller
can effectively control the load disturbance. The combination of the compensation controller
and the integral feedback controller can make up for their own defects and improve the control
performance, in which the follow-up control reflects the actual control process. The three
model transformation methods (including the eigenvalue method, the logarithmic matrix
expansion method and the successive approximation method) proposed in this chapter prove to
be the effective methods by the practical results and have shown that they are applicable to set
up the hierarchical estimator and compensation controller.

The following is calculation formulation (N¼194, m¼20):
N
X
1
M ¼ Z k
N
k¼1
N
X
1
2
S ¼ ð Z k μÞ 2
N
k¼1
N τ
X Z k μ Z k + τ μ
1
^ ρ ¼ ,τ ¼ 0,1,⋯,m
τ
N S S
k¼1
8
^ ρ ,l ¼ 1
>
1
>
>
> l 1
X
^
>
> ϕ ^ ρ
> ^ ρ
< l l 1, j l j
^
ϕ ¼ j¼1 ,l ¼ 2,3,⋯,m
ll
>
>
l 1
> X
> ^
1
> ϕ ^ ρ
> l 1, j j
>
:
j¼1
where
^
^
^ ^
ϕ ¼ ϕ l 1, j ϕ ϕ l 1,l j , j ¼ 1,2,⋯,l 1
lj
ll