Moons' MBDV Series - Calculation Method of Regenerative Energy

36
Rev. 2.0
07/27/2023
MBDV Hardware Manual
4.7.1 Calculation method of regenerative energy
A. Reciprocating motion
When the motor decelerates, the kinetic energy during deceleration will be converted into electric
energy and fed back to the bus capacitor. The energy during deceleration is divided into two parts:
A) Energy generated when the motor decelerates
B) Energy generated during deceleration of external load
The following provides a simple method to quickly calculate the required regenerative energy
absorption resistor.
1) Calculate the energy E M when the motor decelerates
The following table shows the energy generated by the MBDV series servo motor decelerating
from 3000rpm to 0rpm without external load.
Motor
series
Motor
Power (W)
Servo motor model
Rotor inertia
J
M
(10
-4
Kgm)
The energy
generated by
decelerating from
3000rpm to 0rpm
E
M
(J)
Maximum energy absorbed
by the driver capacitor
E
C
(J)
M2
100
SM0402JSL****
SM0402GSL****
0.043 0.21 8.7
200
SM0601J*L****
SM0601G*L****
0.152 0.75 8.7
400 SM0602G*L**** 0.243 1.20 13
750 SM0803G*L**** 0.856 4.22 27
2) Calculate the energy EL produced by the dragged load during deceleration
N times the inertia of the motor, the energy generated when the dragged load decelerates from
3000rpm to 0rpm is:
E
L
=NxE
M
if E M + E L < E C, that is, during the deceleration process, the energy generated by the motor and
the dragged load is less than the energy absorbed by the drive capacitor, so there is no need to
worry about the problem of regenerative energy absorption.
3) Calculate the required average power P
AV
of the regenerative energy absorption resistor
Note: t
dec
is the deceleration time + the interval time between two decelerations