Transtechnik ServoPac GDPS, Руководство пользователя

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7 Chapter 1 - Specifications
ServoPac GDPS – Power supply unit
1.5 – SIZING OF THE POWER SUPPLY
1.5.1 – C
ONTINUOUS POWER
For a reliable and safe operation of the installation, the continuous average power needs to be evaluated for all
axes.
Various ways to proceed for evaluating the continuous power of a machine are listed below:
Accurate method:
The power can be calculated by the absolute value average of the mechanical power for each axis.
∑
> < = N
n axis mechanical GDPS average
P Abs P
1
. . .
) (
Example for one axis:
) 4 5 .( 4 .
2
1
) 3 4 .( 3 .
2
1
) 2 3 .( 2 .
2
1
) 1 2 .( 1 .
2
1
.
ω ω ω ω ω ω ω ω
− + − + − + − =
T T T T P
GDPS average
With:
T: Torque value in Nm (positive when the speed increases)
ω
: Speed value in rad/s
Simplified method 1:
If the continuous average power cannot be evaluated by the "accurate method", it may be convenient to use the
power of the application motors.
The electrical power can be evaluated by the mechanical power divided by the electromechanical efficiency.
If motors have been correctly sized, the average power can be evaluated by means of the following formula:
∑
= N
N
n motor rated
GDPS average
P
P
1
. .
.
η
With
9 . 0
≈
η
Simplified method 2:
If the continuous average power cannot be evaluated by the "accurate method", it may be convenient to define a
service ratio (K
S
) for each drive.
In this case, the average power can be evaluated by means of following formula:
∑
× = N
n axis rated S GDPS average
P K P
1
. . .
With:
4 . 0
≥
S
K
n axis rated n axis rated
I U P
. . . .
3
× × =
Speed
Torque
abs(Power)
Average
ω
1
ω
2
ω
4
ω
5
T1
T2
T3
T4
ω
3