Regenerative Energy Absorption; Calculating The Regenerative Energy - Omron R88D-KN series User Manual

4-4

Regenerative Energy Absorption

A Servo Drive uses its built-in capacitors to absorb the regenerative energy produced during Linear
Motor deceleration. If the amount of regenerative energy is too much for the built-in capacitors to
absorb, it also uses an Internal Regeneration Resistor. An overvoltage error occurs, however, if the
amount of regenerative energy from the Linear Motor is too large. If this occurs, reduce the regenerative
energy by changing operating patterns or increase the regeneration process capacity by connecting
External Regeneration Units.
Additional Information
• Some Servo Drive models do not have any built-in Internal Regeneration Resistor.
• The regeneration absorption capacity of a Servo Drive varies depending on the Servo Drive
model.
For information on whether or not your Servo Drive has an Internal Regeneration Resistor and its
regeneration absorption capacity, refer to 4-4-2 Servo Drive Regeneration Absorption Capacity
on page 4-53
4-4-1

Calculating the Regenerative Energy

This section describes how to calculate the regenerative energy for the horizontal axis.
Motor operation
Motor output torque
In the output force graph, acceleration in a positive direction is shown as positive, and acceleration in a
negative direction is shown as negative.
The regenerative energy values in each region can be derived from the following equations.
V , V : Speed of deceleration
2
1
, F
F :
D2
D1
t , t :
2
1
Note Due to the loss of motor winding resistance and PWM, the actual regenerative energy will be approx. 90% of
the values derived from these equations.
G5 Series AC Servo Drives With Built-in EtherCAT Communications, Linear Motor Type
+ V
1
F
D1
E E
g1 g1
t
1
Deceleration force
Deceleration time
- V
2
T
[mm/s]
[N]
[s]
4 System Design
F
D2
E E
g2 g2
t
2
4
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