3.2.3 AutomationDrive FC 301 vs. AutomationDrive FC 302 Control Principle
AutomationDrive FC 301 is a general purpose adjustable frequency drive for variable speed applications. The control principle is based on Voltage Vector
Control (VVC
plus
).
AutomationDrive FC 301 can handle asynchronous motors only.
The current sensing principle in AutomationDrive FC 301 is based on current measurement in the DC link or motor phase. The ground fault protection
on the motor side is solved by a de-saturation circuit in the IGBTs connected to the control board.
Short circuit behavior on AutomationDrive FC 301 depends on the current transducer in the positive DC link and the desaturation protection with feedback
from the 3 lower IGBTs and the brake.
Figure 3.1: AutomationDrive FC 301
AutomationDrive FC 302 is a high performance adjustable frequency drive for demanding applications. The adjustable frequency drive can handle various
kinds of motor control principles such as U/f special motor mode, VVC
plus
or Flux Vector motor control.
AutomationDrive FC 302 is able to handle permanent magnet synchronous motors (brushless servo motors) as well as normal squirrel cage asynchronous
motors.
Short circuit behavior on AutomationDrive FC 302 depends on the 3 current transducers in the motor phases and the desaturation protection with feedback
from the brake.
Figure 3.2: AutomationDrive FC 302
FC 300 Design Guide
3 Introduction to AutomationDrive FC 300
MG.33.BC.22 - VLT
®
is a registered Danfoss trademark
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