
Fundamentals of AC–DC–AC Converters Control and Applications 16-11
Based this equation, the direction and velocity of the line current vector changes depends on
• Values of input chokes L
•
L
ine voltage vector U
Lxy
• Line current vector I
Lxy
• Value of the DC-link voltage U
dc
• Switching states of the VSR S
1xy
Command current I
Lxyc
is in phase with line voltage vector U
Lxy
and it lies on the axis x. e dier-
ence
b
etween
a
ctual
c
urrent
I
Lxy
and commanded I
Lxyc
is dened by Equation 16.8 and is illustrated in
F
igure
1
6.9.
Full
c
urrent
c
ontrol
i
s
p
ossible
w
hen
t
he
c
urrent
i
s
k
ept
i
n
d
esired
e
rror
a
rea
(
16.9).
C
ritical
o
peration
o
f
t
he
V
SR
i
s
w
hen ...