Need help with a sensorless vector VFD and 2.2kw motor.

**audioandy** · 03-02-2014

My understanding of vector mode it will only work at 50Hz and below.

Try setting your max frequency to 50Hz then see if the vector mode works.

Andy

**EddyCurrent** · 03-02-2014

Andy,
I don't know about this particular VFD but the ABB I'm using goes up to 400 Hz in vector mode, in fact the reference signal on the keypad changes from Hz in v/f mode to RPM in vector mode.

**audioandy** · 03-02-2014

Originally Posted by EddyCurrent

Andy,
I don't know about this particular VFD but the ABB I'm using goes up to 400 Hz in vector mode, in fact the reference signal on the keypad changes from Hz in v/f mode to RPM in vector mode.

Hi Eddy

That's interesting does that mean you get high torque at the bottom end of the frequency range?

If so can you let me have the part number please.

Regards

Andy

**EddyCurrent** · 03-02-2014

ABB ACS355 2.2kW 230V 1ph to 3ph - Vector Control AC Inverter Drive Speed Controller - AC Inverter Drives (230V)
ABB ACS-CP-C Basic Control Panel (Keypad) for ACS310, ACS350, ACS355 and ACS550 Inverters (+J404) - Accessories for AC Drives

There's vector torque mode and vector speed mode, you can download the manual from above web site.
Should give full load torque at zero speed.

Be aware though it didn't work right out of the box, see here http://www.mycncuk.com/forums/gantry...html#post54303

I have two of these, the other drives a standard 2.2kW 3000 rpm motor in vector mode and this does work out of the box.

This is a great read too.
http://http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/771cd1d59737abfac1257b0f0046ac22/$file/TechnicalGuideBook_EN_3AFE64514482_RevG.pdf

**kajuk** · 05-02-2014

I've made some progress in vector mode using EddyCurrent's suggestions.
What I did:
Set PB.02 -> 2.2 (Motor rated power)
Set PB.03 -> 100 instead of 400 (Motor rated frequency)
Set PB.04 -> 6000 instead of 24000 (Motor rated speed(RPM))
Set PB.05 -> 55 instead of 220 (Motor rated voltage)
Set PB.06 ->10 (Motor rated current)

Then I run autotuning (PB.00 -> 1)
After autotuning finishes:
Set PB.08 -> 00.050 (Motor rotor resistance). This is the most important! . After autotuning it is set to 00.000.
Then, without touching PB.02 (power rating. if changed, it resets all detected tuning parameters):
Set PB.03 -> 400 (Motor rated frequency)
Set PB.04 -> 24000 (Motor rated speed(RPM))
Set PB.05 -> 220 (Motor rated voltage)

After that it seems to work in vector mode. A few notes though:
1. It won't spin high than around 14000rpm (~233Hz). When approaching this speed or going beyond, it oscillate for a few seconds around 14000rpm and then steadies itself at this speed.
1. I can feel it increases torque at low rpm. When in v/f mode at ~1000rpm I can easily stop the spindle with my hand (in a glove), when in vector mode it feels like I have to use 2-3 times more force to stop the spindle. Is this how much it should be expected from vector mode?

**EddyCurrent** · 05-02-2014

An improvement but not quite there.
Yes you should get full torque from zero to full speed.
Change PB.04 to 5775 and see if that makes a difference.
P0.06 should be 15Khz

**kajuk** · 05-02-2014

Originally Posted by EddyCurrent

An improvement but not quite there.
Yes you should get full torque from zero to full speed.

By this, do you mean I shouldn't be able to stop the spindle with a hand at any low rpm?

Change PB.04 to 5775 and see if that makes a difference.

I guess before running autotuning. I'll try.

**EddyCurrent** · 05-02-2014

Originally Posted by kajuk

By this, do you mean I shouldn't be able to stop the spindle with a hand at any low rpm?

2.2kw is not that powerful, I've not tried it but I imagine with a good grip you could stop it at low speed.

Originally Posted by kajuk

I guess before running autotuning. I'll try.

Yes, as you know as soon as you change the motor parameters you have to do the autotune again.

**kajuk** · 06-02-2014

Just tried it but it didn't improve beyond what I already got. Also to note is that I can set speed between around 800rpm and 14000rpm. Below 800rpm it just stops. At ~1000rpm the current is ~3A, goes up to around ~5A at ~10000rpm and goes down to ~4A at ~14000rpm.

**EddyCurrent** · 06-02-2014

The current is similar to mine.
I've just noticed you did not ratio the kW, you should set PB.02 to 0.55kW
If that does nothing then ABB at first were thinking about putting parameters in as if the motor was 50Hz 3000rpm but then realised this would not work so they opted for 50% settings 200Hz 12000rpm and it worked. I'm thinking therefore that you could try other ratios that are closer to the 50% settings.
e.g. 7200rpm 120Hz 66V 0.66kW