YOKOGAWA DrvPIII UR5AP3, Техническая информация, Страница: 82 / 326

5-24
TI 71M01D06-01EN 3rd Edition: 2012.12.01
3 3
8 . 0 2
1
× ×
+
× × ×
× ×
=
in f
L
in f m
p
E P
D
E P
T N
I
η
π
3
) ( 1
p
rms
I
I
=
3 3
) ( 2
2
2
× ×
+
× × ×
+ ×
=
in f
L
in f m
LL LB
E P
D
E P
T T N
I
η
π
cy
rms
rms
in
t
t I t I
I
2
2
2 1
2
) ( 1
) (
× + ×
=
A I 17 . 4
3 230 5 . 0
45
3 230 5 . 0 6 . 0
) 0 50 ( 05 . 1 2
2
=
× ×
+
× × ×
+ ×
=
π
Obtain the maximum current lp at acceleration from the motor torque and maximum velocity.
The motor efficiency varies with the velocity and torque. Here it is estimated at 60%. Note that
80% of the maximum torque is used for the motor torque. Since 3-phase input is used, the
input current per phase is multiplied by a factor of
3
1
.
Obtain the effective current at acceleration I
1 (rms)
:
Obtain the current I
2
at a constant velocity:
Obtain the effective input current I
in (rms)
:
Example of Calculation
The rated currents of a circuit breaker and filter are calculated under the following operating
conditions:
Obtain the maximum current
l
p
:
Obtain the effective current at acceleration l
1 (rms)
:
Obtain the current at a constant velocity l
2
:
Obtain the effective input current l
in (rms)
:
Thus, the rated current is "4A."
Be sure to verify that the value of
l
p
is within the operation characteristic curve for the selected
circuit breaker and fuse.
N : Maximum motor velocity (rps)
T : Motor torque (N-m)
D
L1
: Drive loss at acceleration (W)
D
L2
: Drive loss at a constant velocity (W)
η
m
: Motor efficiency 60%
P
f
: Power factor 0.5
E
in
: Power supply input voltage (V)
T
LB
: Bearing torque Torque/10 (N-m)
T
LL
: Load torque (N-m)
Motor operation condition
Drive current: 50 A
Motor torque: 500 N-m
Maximum velocity: 1.5 rps
Acceleration/deceleration time: 50 ms
Constant velocity time:
100 ms
Stop time: 100 ms
Cycle time: 300 ms
Power supply input voltage: 230 V
Load friction:
0 N-m
A I
p
75 . 32
3 230 5 . 0
300
3 230 5 . 0 6 . 0
8 . 0 500 5 . 1 2
=
× ×
+
× × ×
× × ×
=
π
A I
rms
9 . 18
3
75 . 32
) ( 1
= =
A I
rms
in
95 . 13
3 . 0
1 . 0 17 . 4 05 . 0 75 . 32
2 2
) (
=
× + ×
=