Hiwin D1-N Series - Page 34

D1-N Series Servo Drive User Manual Operation Principles
3-10 HIWIN MIKROSYSTEM Corp.
MD17UE01-1906
Figure 3.6.1.1 Gain margin
(2) Phase margin
As figure 3.6.1.2, phase margin is the angle between the straight line passing through gain crossover
and the negative real axis of
)(
ω jG
-Plane.
Phase margin = PM =
°−∠ 180)(
g
jG ω
Figure 3.6.1.2 Phase margin
)
(
p
j
G
ω
0
p
ωω =
G
Re
G
j
Im
(
)
Plane
j
G
−
ω
Phase crossover
ω ←0
0
g
ωω
=
G
Re
G
j
Im
(
)
Plane
j
G
−
ω
Gain
crossover
ω ←0
1
-1
Phase margin