0195136047.pdf

PROBLEMS 825

ea

ea

Constant field

or permanent

magnet

Constant field

or permanent

magnet

(a)

Electronic instrument

such as dc millivoltmeter

with high impedance

vo RL

ωm

ωm

ia Ra La

ei

(b)

Ra La

JL, BL

ia

Figure P16.2.26

G(s)

H(s)

Loop 3

Loop 2

Loop 1

R(s)

(a)

+ C(s)

+

G 1 G 2 G 3 C

H 1

R

(b)

+

−

H 2

H 3

+

+

−

Figure P16.2.27

16.2.32Verify the error-response conclusions listed in
Table 16.2.2.
16.2.33(a) Determine the system type, the steady-state
error for a unit-step reference function, and
the closed-loop time constant for the speed-
control system of Figure P16.2.33(a), which
uses proportional control.
(b) Determine the system type, the steady-state

error for a unit-step reference function, and

the damping ratio for the speed-control sys-

tem of Figure P16.2.33(b), which uses integral

control.

(c) Add proportional control to the system of part

(b) by replacingKi/swithKp+Ki/s, and

find the new damping ratio.

*16.2.34Consider the speed-control system shown in