3-72
Engineering Guide CDA3000
3 Selection of inverter module
3.3.4 70 Hz charac-
teristic with
25% field
weakening
Traction and lifting drives which operate with 25% field weakening (70 Hz
maximum frequency) offer a wide variety of advantages:
−
40% more break-away and acceleration torque can be attained
without increasing the cost of the inverter drive solution.
−
Greater economy can be achieved based on saving on an exter-
nal cooler or reducing the motor power output by one type step.
Example: Drive design with 50 Hz (F
max
= 50 Hz) and 70 Hz character-
istic (F
max
= 70 Hz)
−
Speed manipulating range from 20 to 95 rpm on the gear output
shaft
−
Output torque on gear output shaft of 150 Nm
−
Operation mode: S1 (continuous operation), ED = 100%
−
There is no time requirement for the startup and braking
response.
Operation of a motor
with 25% field weak-
ening
Area of application of solution:
•
In applications such as traction and lifting drives.
For more information see section 3.3.4
Operation of a motor
with 87 Hz character-
istic
Area of application of solution:
•
In applications such as traction and lifting drives with
expanded manipulating range at constant torque delivery.
For more information see section 3.3.5
Several motors on one
inverter module
Area of application of solution:
•
In conveying, textile machinery engineering etc.
For more information see section 3.3.6
Design (solution)
Application
Table 3.34
Special applications