Yaskawa SGDH Linear Sigma Series - Manual (Page 383)

12.2 Calculating the Required Capacity of Regenerative Resistors
12-7
12
12.2.2 Calculating the Regenerative Energy
This section shows the procedure for calculating the regenerative resistor capacity when acceleration and decel-
eration operation is as shown in the following diagram.
(1) Calculation Procedure
The procedure for calculating the regenerative capacity is as follows:
Note: 1. The “0.2” in the equation for calculating W
K
is the value for when the regenerative resis-
tor’s utilized load ratio is 20%.
2. The units for the various symbols are as follows:
Motor speed
Motor force
F
L
: Load force
t
D
0
0
Regenerative
force
V
M
: Motor speed
T
Step Item Symbol Equation
1 Calculate the kinetic energy of the linear ser-
vomotor. E
S E
S
= MV
M
2
/2
2 Calculate the energy consumed by friction
loss during the deceleration period. E
L
E
L
= V
M
F
L
t
D
/2
3 Calculate the energy lost from linear servo-
motor winding resistance. E
M
(Value calculated from “(2) Servo-
motor Winding Resistance Loss”
diagrams)
×
t
D
4 Calculate the SERVOPACK energy that can
be absorbed. E
C
Calculate from “(3) SERVO-
PACK’s Absorbable Energy” dia-
grams.
5 Calculate the energy consumed by the regen-
erative resistor. E
K
E
K
= E
S
− (E
L
+E
M
+E
C
)
6 Calculate the required regenerative resistor
capacity (W). W
K
W
K
= E
K
/ (0.2 × T)
Symbol Units Meanings
E S
J Kinetic energy of linear servomotor
E L Energy consumed by friction loss during the deceleration period
E M Energy consumed by linear servomotor winding resistance loss
E C Energy that can be absorbed by SERVOPACK
E K Energy consumed by regenerative resistor
W K W Required capacity of regenerative resistor
M(=M M +M L ) kg Load mass including linear servomotor
V M m/s Linear servomotor movement speed
F L N Load force
t D
sec Period to decelerate to a stop
T Repeated operation cycle of linear servomotor