DC Injection Braking (Full Lecture) 

I am from HK. I love your lecture very much. Thanks a lot. Keeping going.

I was taught as you explained here, nevertheless, I found that PowerFlex 525 from Allen Bradley has a parameter to set a DC braking time after the deceleration ramp. I was curious how they could implement this without damaging the motor. To this point I believe they make use of brake resistor in combination with the DC current injection and feeding one coil at a time with a defined duty cycle. But, that is just my guess. The thing is, it works, I had an issue with a conveyor that after the deceleration ramp (by inertia I assume) it continued to move for a couple of seconds until completely stops, even though it was already stopped before. I moved that parameter and it's definitively holding the motor 1 extra second after it fully stop.

How do you figure how large of a power supply you need?

Do you have any book as reference for this, or a circuit of the system?

does dc injection braking may cause significant unbalance currents supplied to vfd???

hi jim: do you have a skype account, some hydraulic question want to ask.