Regenerative
Torque T applied to servo motor [N•m]
power
(1)
T
1
(2)
T
2
(3)
T
3
(4), (8)
T
, T
4
(5)
T
5
(6)
T
6
(7)
T
7
*1 Load torque converted into equivalent value on servo motor shaft TL can be calculated with the following formula. T
g)) × ΔS} / (2000 × π × η)
*2 Load moment of inertia converted into equivalent value on servo motor shaft JL can be calculated with the following formula. J
J
+ J
J
is the load moment of inertia of the moving part, J
L2
L3
L1
moment of inertia of the coupling. J
0.0078 × (L
/ 10)) / 32} × (D
B
From the calculation results in (1) to (8), find the absolute value (Es) of the sum total of negative energies.
■Losses of servo motor and servo amplifier in regenerative mode
The following table lists the efficiencies and other data of the servo motor and servo amplifier in the regenerative mode.
Servo amplifier
MR-J5W2-22G_
MR-J5W2-44G_
MR-J5W2-77G_
MR-J5W2-1010G_
MR-J5W3-222G_
MR-J5W3-444G_
Inverse efficiency (η
m
torque is generated at rated speed. Efficiency varies with the speed and generated torque. Because the characteristics of the
electrolytic capacitor change with time, allow inverse efficiency of approximately 10 % higher than those shown above.
Capacitor charging (Ec): Energy charged into the electrolytic capacitor in the servo amplifier
6 OPTIONS AND PERIPHERAL EQUIPMENT
182
6.2 Regenerative option
(J
/η + J
) • N
1
L
M
•
+ T
=
L
4
9.55 • 10
t
psa1
= T
L
-(J
• η + J
) • N
1
L
M
•
+ T
=
L
4
9.55 • 10
t
psd1
= 0
8
(J
/η + J
) • N
1
L
M
•
+ T
=
L
4
9.55 • 10
t
psa2
= T
L
-(J
• η + J
) • N
1
L
M
•
+ T
=
L
4
9.55 • 10
t
psd2
and J
can be calculated with the following formulas. J
L1
L2
4
/ 10)
B
): Efficiency including some efficiencies of the servo motor and servo amplifier when rated (regenerative)
*1*2
Energy E [J]
0.1047
E
=
1
E
= 0.1047 • N • T
2
0.1047
E
=
3
E
, E
= 0 (No regeneration)
4
8
0.1047
E
=
5
E
= 0.1047 • N • T
6
0.1047
E
=
7
is the load moment of inertia of the ball screw, and J
L2
Inverse efficiency [%]
85
90
90
90
85
90
• N • T
• t
1
psa1
2
• t
2
1
• N • T
• t
3
psd1
2
• N • T
• t
5
psa2
2
• t
6
3
• N • T
• t
7
psd2
2
= W
× (ΔS / (20 × π))
L1
L
Capacitor charging [J]
17
21
44
44
21
31
= {(F
+ (μ × W
×
L
C
L
= J
+
L
L1
is the load
L3
2
J
= {(π ×
L2