Solution 8.8.6
The transfer function of the motor is
G(s)=
K
(s+p
1
)(s+p
2
)
;;
Then the step response is
C(s)=
V
arm
K
s(s+ p
1
)(s+p
2
)
=
A
s
+
B
s+ p
1
+
C
s+ p
2
:
Then
A =
V
arm
K
(s+p
1
)(s+s +p
2
)
s=0
=
V
arm
K
p
1
p
2
:
Thus,
K =
Ap
1
p
2
V
arm
:
Thus, to nd the unit step response wehavetomultiply the steady output
A by the product of the poles and then divide bythearmature voltage.
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