![Infineon XDPP1100 Скачать руководство пользователя страница 111](http://html1.mh-extra.com/html/infineon/xdpp1100/xdpp1100_technical-reference-manual_2055193111.webp)
User Manual
111 of 562
V 1.0
2021-08-25
XDPP1100 technical reference manual
Digital power controller
Compensator
•
Integral term output, I_term
•
Voltage FF term, ff_duty
The implementation of the post-filter is illustrated in
Figure 50
Post-filter block diagram
The post-filter creates the second high-frequency pole, f
p2
, in the compensator transfer function. The pole
location (i.e., LPF BW) is defined by the filter coefficient K
FP2
, which is programmable through register
pid_kfp2_index_1ph
.
Similarly to the pre-filter, K
FP2
_index uses exponent mantissa format to provide an extended range using fewer
total bits. The upper three bits of K
FP2
_index represent the exponent and the lower three bits represent the
mantissa. The integer and real number representations of K
FP2
are computed as given in Equations (6.21) to
(6.24). Note that K
FP2
_index is clamped to 55, internally corresponding to a maximum exponent of 6.
𝐾
𝐹𝑃2
_𝑒𝑥𝑝 = 𝑀𝐼𝑁(6, 𝐾
𝐹𝑃2
_𝑖𝑛𝑑𝑒𝑥[5: 3])
(6.21)
𝐾
𝐹𝑃2
_𝑚𝑎𝑛 = (𝐾
𝐹𝑃2
_𝑖𝑛𝑑𝑒𝑥[5: 3] > 6)? 7: 𝐾
𝐹𝑃2
_𝑖𝑛𝑑𝑒𝑥[2: 0]
(6.22)
𝐾
𝐹𝑃2
= (8 + 𝐾
𝐹𝑃2
_𝑚𝑎𝑛) ∗ 2
𝐾
𝐹𝑃2
_𝑒𝑥𝑝
(6.23)
𝐾
𝐹𝑃2
_𝑟𝑒𝑎𝑙 = 𝐾
𝐹𝑃2
∗ 2
−13
(6.24)
The location of the second high-frequency pole can be computed as provided in Equation (6.25), using the
previously computed real number representation for K
FP2
.
𝑓𝑝2 = (
1
2𝜋𝑇
𝑆𝐴𝑀𝑃𝐿𝐸
) (
𝐾
𝐹𝑃2
_𝑟𝑒𝑎𝑙
1−𝐾
𝐹𝑃2
_𝑟𝑒𝑎𝑙
) , 𝑇
𝑆𝐴𝑀𝑃𝐿𝐸
= 50 𝑀𝐻𝑧
(6.25)
The corresponding integer and real number representations of K
FP2
for each K
FP2
_index value are the same as for
K
FP1
provided in
in the pre-filter
. Correspondingly, the post-filter BW as a function of
parameter K
FP2
_index is the same as shown in
6.1.4
Input/output clamping of the compensation filter
The input and the output of the PID filter can be clamped. The input clamp is user-programmable through
register
vsp_verrn_clamp_thresh
, as discussed in
, and it limits the maximum error seen by the
compensation filter.
Clamp
D
Q
pd_term
S8.16
S5.29
K
FP2
U-3.13
S1.20
S1.20
S3.20
S3.16
U0.16
S1.15
+
+
+
+
-
1
0
D
Q
0
1
C
C
C
pid_force_duty
pcmc_mode
pid_en_force_duty
i_term
S1.16
ff_duty
U0.10
+
duty cycle
U0.16/S1.15
K
FP2
U-3.13
S2.53
S1.20