I am putting a current limit loop in the VFD for my 125hp 3-phase AC Induction Motor.
My scheme is to get the current feedback from my DSP board. If the current is over a certain limit level, say 300A, I will lower my commanded frequency f so that the voltage drops. (I use v/f scalar control)...
I am using a VFD to drive a 3-phase AC Induction motor. A v/f scalar control method is used.
Many textbooks define such motor working range is usually from 8 or 10hz to, say, 60hz. I think that is because the torque is insufficient to drive the motor at the low-speed range. So, I would like to...
I would add in a current loop in the code of my VFD for a 3-phase AC induction motor (125hp) to control the current.
As I am using V/f scheme to control the motor, if the current is too large or small, I need to adjust the voltage applied to the motor based on the current values (I can...
What is difference between "auto boost" and "torque boost" during AC Induction motor start? If the motor has no load, is that possible to make the motor work at low speed range, say under 10hz?
Thanks!
I have met a few problems in starting a 125hp (460V) AC Induction Motor:
1. I use v/f control method. When I start the motor, the motor trips out as my inverter can only handle 400A and the startup current (Locked rotor current) is over than that. For the pull-up torque: T = k * B * I *...
