openinverter forum

I have made a dual Huebner controler drive on a single Volt inverter platform.

Idea was to use two power stages independently from one another. Both support resolver interfaces.
So for the first controler i uses 4.90R FOC PMSM drive connected to one Outlander motor.
The second motor is ACIM and i have 4.90R sine firmware loaded.
First brain is master and keeps the precharge and DC switch controls. Both drives are shown DC voltage through a single iso opamp.
I have succesfuly started inverter on 90Vdc and spun the PMSM motor and ACIM motor at the same time.

However i see a problem with resolver interface. Or does it just seem that way. Immediately when i start and apply throttle motor jumps and spins up to max RPM. No ammount of throttle does anything to change that. Also i limited RPM with parameter fmax but it doesnt really behave.
And the error brain shows is throttle error. But as i measure throttle it slides OK and moves from 1200pr to 4000pt easily.
I will try to make a video and demonstrate the problem.

Motor is lacrosse 18kW ACIM motor with resolver.
8 motor poles
2 resolver poles
I run inverter at 93Vdc.

I have actually figured out motor is 8pole and resolver seems to be 4 pole.
I consider this successful ACIM running on resolver interface, save for some anomalies.
Although this setting lets me control the motor by throttle its start and any torque is acompanied by rough running and vibration.
Phase amp draw is some 80A while DC current draws about 30A from 90V battery.

arber333 wrote: ↑Sun Sep 20, 2020 6:50 pm I have actually figured out motor is 8pole and resolver seems to be 4 pole.
I consider this successful ACIM running on resolver interface, save for some anomalies.
Although this setting lets me control the motor by throttle its start and any torque is acompanied by rough running and vibration.
Phase amp draw is some 80A while DC current draws about 30A from 90V battery.

Great progress getting the lacrosse motor running but some serious tuning needed. The Hyundai HSG, which is a similar sized IPM motor, draws ~2A at 6200 rpm on 190V and only 0.8A at 2150rpm on 69V.

kiwifiat wrote: ↑Mon Sep 21, 2020 2:16 am Great progress getting the lacrosse motor running but some serious tuning needed. The Hyundai HSG, which is a similar sized IPM motor, draws ~2A at 6200 rpm on 190V and only 0.8A at 2150rpm on 69V.

I am not sure how i can reliably tune this beastie since i dont have a vehicle handy to load it.
Also i dont see that many parameters that needs to be changed. There are "boost", "fslipmin", "ampmin" and "fslipmax".
In any case last evening i connected my scope and observed both resolver signals and compared sin- FOC vs sin- slip. I noticed some differences in signal clarity and consistency. The same applies to cos signal. I may have to inspect my resolver circuit for integrity.

Obvious question Arber, have you had a chance to look at OpenInverter FOC Tuning yet?



kind regards,

Oh yes, FOC for PMSM motors, sine firmware for ACIM motors, answered my own question.

kiwifiat wrote: ↑Mon Sep 21, 2020 2:16 am Great progress getting the lacrosse motor running but some serious tuning needed. The Hyundai HSG, which is a similar sized IPM motor, draws ~2A at 6200 rpm on 190V and only 0.8A at 2150rpm on 69V.

I managed to get Lacrosse motor spinning with resolver control very smoothly. I seem to have a problem inside resolver circuit on snd stage. 1st stage was running the motor great.

Well last week i finally managed to trace the weird resolver signal to seemingly good caps. They were from a different series than my usual ceramic caps. I went on and replaced them and i get good resolver signal. Also the pesky Lacrosse motor is now running really good with resolver and 100Vdc battery.

Now i am having some problems with starting PWM on my first power section. It keeps falling into OC limit.
I am thinking something happened to current sensor resistor divider. Johannes can you tell me again how much is correct for inverter to sense current sensors centered? I see 1.67V on the divider. Should i see more?

1.67 is perfect

johu wrote: ↑Sat Apr 03, 2021 3:04 pm1.67 is perfect

Tnx
Why is it then i am consistently getting OC from the FOC brain when i start? ACIM code is working good.
Also i tried swapping currrent sensors 12 in software and there is no difference in OC behaviour.
EDIT: I was able to start motor by hand with M10 socket from the back . So when i turn it and hold start button i hear resolver and PWM start. I also hear throttle response in PWM, but i can get no RPM. I need to find the syncoffset again. But i clearly cant get to manual start. I still get OClimit.

Now i noticed your newer code pinswap values go all the way to 15? Do you have a table on the values maybe? I hate guessing.

tnx

Well...strange. I found a frequency on Olimex pin PB12! It is 55kHz and it changes in duty when i push start button.
Since PB12 is signalling HW stop to everything i expected it is caused by faulty Olimex. But no when i used the same chip in place of ACIM power stage it works fine. And if i replace it with ACIM coded one it still makes that frequency. Faulty NAND gate? But why would it output such consistent frequency? I will replace NAND and try again...

arber333 wrote: ↑Sat Apr 03, 2021 4:22 pm Now i noticed your newer code pinswap values go all the way to 15? Do you have a table on the values maybe? I hate guessing.

0=None, 1=Currents12, 2=SinCos, 4=PWMOutput13, 8=PWMOutput23

If you find out which PWM channel is measured by which current sensor it is easy to calculate.
SinCos swap is just convenience to try out whether you swapped it in hardware.

Thanks J

In the meantime i figured i have a problem with 3V3 supply from both brain. As soon as i connect WiFi module i immediately get OClimit. It seems AD reference moves enough that brain detects this as OC. I will order a small 5V to 3V3 supply and report later...

Would you be willing to share the schematic of your board, as you've already done all the reverse engineering on the inputs to the controls? I'd be interested in messing around with volt inverters, as they've gotten pretty inexpensive around here.

Edit: Didn't notice the other thread, taking a look at it there.