Stober 56690, Руководство пользователя

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STOBER 6 | Project configuration
05/2019 | ID 442790.01
55
Calculating motor rating and voltage
The following formulas and assumptions are used to calculate the motor rating and voltage:
MOT MOT MOT MOT
P 3 U I cos
= ´ ´ ´ j
Line Line Line,nec Line
P 3 U I = ´ ´ ´ l
max MOT LINE
U 0,8 U
= ´
MOT MOT
minLINE MOT
LINE LINE
U cos
I I
U
j
= ´ ´
l
In addition, the field weakening range begins.
The active factor for a synchronous servo motor (cos φ
MOT
) is about 0.9 in 4 kHz operation and about 0.98 in 8 kHz
operation. The active factor of an asynchronous motor can be determined according to the accompanying electrical data.
The following is true for the power factor of the supply grid:
LINE LINE
0,6 I 40A
l = ® <
LINE LINE
0,7 I 40A
l = ® >
The required motor rating must be calculated in order to determine the necessary supply current and the number and sizes
of the drive controllers to be connected to the grid as part of Quick DC-Link.
The overall maximum permitted input current I
maxLINE
is the sum of the maximum input currents of all connected drive
controllers in continuous operation. Dynamic movements of the connected motors are possible in the permitted range.
The following is true for the sum of the input currents of the connected drive controllers:
§ If the respective power of all drive controllers connected to the grid is identical, the sum of the maximum input
currents in the network is calculated using the formula
m axLINE fed 1N,PU
I 0,8 n I = ´ ´
§
If the respective power of all drive controllers connected to the grid differs, the sum of the input current is calculated
by multiplying the input current of the smallest drive controller connected to the grid by the number of connected
drive controllers
max LINE fed IN,PUmin
I 0,9 n I = ´ ´
To prevent current asymmetry, all drive controllers connected to the grid with different ratings must contain the same fuse
protection, which in turn must correspond to the drive controller with the least power.
Current load capacity of the copper rails
DC rails connect the DC link capacitors of the drive controllers with one another. They are copper rails that are installed
using the quick fastening clamps. DC rails must have a cross-section of 5 x 12 mm. The maximum permitted current load
capacity of the copper rails is 200 A.
Wiring example
The example in the chapter Wiring examples [ } 193] illustrates the basic connection to Quick DC-Link DL6B based on a DC
link connection.