User Manual
103 of 562
V 1.0
2021-08-25
XDPP1100 technical reference manual
Digital power controller
Compensator
Figure 49
PID computation block diagram
Similarly to the pre-filter, the PID parameters use an exponent mantissa format to provide an extended range
using fewer total bits:
•
The upper three bits of K
P
_index and K
I
_index represent the exponent and the lower three bits represent the
mantissa.
•
For K
D
_index, the upper four bits represent the exponent and the lower three bits represent the mantissa.
The integer and real number representations of K
P
are computed as provided in Equations (6.7) to (6.10).
𝐾
𝑃
_𝑒𝑥𝑝 = 𝐾
𝑃
_𝑖𝑛𝑑𝑒𝑥[5: 3]
(6.7)
𝐾
𝑃
_𝑚𝑎𝑛 = 𝐾
𝑃
_𝑖𝑛𝑑𝑒𝑥[2: 0]
(6.8)
𝐾
𝑃
= (8 + 𝐾
𝑃
_𝑚𝑎𝑛) ∗ 2
𝐾
𝑃
_𝑒𝑥𝑝
(6.9)
𝐾
𝑃
_𝑟𝑒𝑎𝑙 = 𝐾
𝑃
∗ 2
−16
(6.10)
provides the corresponding integer and real number representations of K
P
for each K
P
_index value.
Table 30
K
P
_index to K
P
, K
P
_real
K
P
_index
K
P
K
P
_real
0
8
0.0001
1
9
0.0001
2
10
0.0002
3
11
0.0002
4
12
0.0002
5
13
0.0002
6
14
0.0002
K
D
U1.11
U-5.16
pd_term
S8.16
S4.16
i_term
S7.16
+
+
d_term
p_term
Clamp
Clamp
K
P
U-15.26
K
I
verrn_filt
S9.3
verrn_slope
S8.6
Clamp
D
Q
S1.16
S1.16
S-6.29
S15.12
S1.16
LSB
accum
