
16-26 Power Electronics and Motor Drives
where
M K T K T K CU T CU CU K T
z PU IU PU IU PU dcc IU dcc dcc PU U
( )ω ω ω= + −
+ −
2 2 4 2
2 2
TT
IU dcc UT
T CU T
+
( )
ω
6
2
ω is the frequency domain
Hence, proportional gain K
PU
and integral time constant T
IU
of the DC-link voltage controller can be
calculated as follows:
K
C
T
U
PU
UT
dcc
=
2
(16.53)
T T
IU UT
= 4
(16.54)
Please take into consideration that value of the DC-link voltage lter time constant T
U
has to be deter-
mined. eoretically, it could be equal to one sampling period T
S
. However, in practice the low-pass
lter in DC-link voltage loop is needed. erefore, for further consideration, T
U
= 0.003