ÇUKUROVA UNIVERSITY INSTITUTE OF NATURAL AND APPLIED ...

4. MODELING OF PROPOSED DVR Mustafa İNCİ
Solving for Vo,
V
O
⎛ N
S
VS
D
N ⎟ ⎞
= 2 ⎜
(4.20)
⎝ P ⎠
2011),
It is also useful to express the ripple as a fraction of the output voltage(Hard,
∆V
V
O
O
1−
D
=
8LCf
2
(4.21)
In design, it is useful to rearrange the preceding equation to express required
capacitance in terms of specified voltage ripple(Hard, 2011):
1−
D
C = (4.22)
8L
2
( ∆V
/ V ) f
O
O
If the ripple is not large, the assumption of a constant output voltage is
reason-able and the preceding analysis is essentially valid(Hard, 2011).
Finally, the VA rating of the capacitor, denoted as , is (Li et al., 2001):
S = k V I
(4.23)
C
C
C
C
Where
1.2(Li et al., 2001).
k
C
is an optional safety coefficient, typically ranging from 1.0 to
4.3. Control System
The control system of a DVR plays an important role, with the requirements
of fast response and more accuracy. Many extraction and mitigation strategies is
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