Page 641 - Mechanical Engineers' Handbook (Volume 2)
P. 641
632 Controller Design
Figure 11 (Continued)(d) 2 0.8.
K
G d (12)
d
s 1
1
and
U 1 K d s
2
D K ( /K )s (1/K )s 1 (13)
u1
1
u1
u1
For a position loop
K
G d (14)
d
s( s 1)
1
and
U 1 K d 1
D K ( /K )s (1/K )s 1 (15)
2
u1
1
u1
u1
It is instructive to compare Eqs. (13) and (15) with Eqs. (2) and (4), respectively.
3 FREQUENCY COMPENSATION TO IMPROVE OVERALL PERFORMANCE
In Section 2, it is clear that open-loop dynamic characteristics impose profound limitations
upon closed-loop performance. However, it is often possible to extend these limitations by
