Syncofs searching

[kiwifiat]

@kiwifiat, which chip are you using for resolver to 6 step conversion?

I have the circuit drawn for AU6802N1 chip on my Lebowski board, but i am lacking incentive since Leaf motor is just as good with my RLS modified UVW sensor.
Of course i have AU6802N1 chips scavenged from Prius main board!

Currently I'm using the ATMega328 but intend porting the code across to something with a bit more power. I have designs based on the Tamagawa chip and Analog devices resolver to digital chips but they both require monitoring by a separate CPU so it seems redundant in this case to use a CPU capable of doing the job to monitor for errors and or "clock" another chip.

Regarding your syncofs issue, it seems to me that if syncofs is correct the motor will run identically in CW and CCW directions unless there is asymmetry in the motor or something weird going on with the control algorithm. As previously discussed there is no indication that there is any asymmetry in the Nissan Leaf motor nor the Toyota IPM's for that matter. Given that IPM's produce torque from Id it seems to me that the recommended procedure for finding syncofs will yield an incorrect result. If the motor was an SPM then it would be correct since Id produces no torque. I would keep adjusting syncofs until the motor runs correctly in either direction. Maybe johu can chime in?

[slow67]

Given that IPM's produce torque from Id it seems to me that the recommended procedure for finding syncofs will yield an incorrect result. If the motor was an SPM then it would be correct since Id produces no torque. I would keep adjusting syncofs until the motor runs correctly in either direction. Maybe johu can chime in?

I think this is a valid point. Also the best angle for torque moves around with current. Here is the one for the Lexus trans.

[arber333]

Regarding the rumbling I don't get this with the Leaf motor. What happens if you add 180° (32768) to synofs? Does it spin the other direction smoothly? Otherwise you might still have a twist in current or resolver channels.

It wants to fly away . Seriously, 9500pt is a good offset value for CW, probably i need to polish it some more...

I already swapped current channels. If i return them back i promptly get OCevent. Since current sensors are integrated into a single block it would be difficult to swap them physicaly.
Johannes would you split your pin swapping settings in code and make three different options/parameters? I think it would offer more choice for further designs.

tnx

[arber333]

I think this is a valid point. Also the best angle for torque moves around with current. Here is the one for the Lexus trans.

Hm... what kind of motor is Remy HVH 250? Is it IPM? Certainly some people online think so. But there is no torque on shaft if i rotate it by hand.
It is 10 pole motor with 10 pole resolver. I can see 5 lobes in resolver core.

EDIT:

Remy cites testing showing that an HVH internal permanent magnet motor provides 27% higher torque and 34% higher power compared with the same size round wire winding IPM motor. At the same performance level, the HVH motor offers a 22% reduction in space requirements and 13% reduction in mass. In addition to documented fuel efficiency improvements, freight hauling capacity can be increased since more weight can be carried in the vehicle rather than in the hybrid drivetrain.

[johu]

Given that IPM's produce torque from Id it seems to me that the recommended procedure for finding syncofs will yield an incorrect result. If the motor was an SPM then it would be correct since Id produces no torque. I would keep adjusting syncofs until the motor runs correctly in either direction. Maybe johu can chime in?

No there is neither reluctance nor magnetic torque if the field is perfectly aligned with the magnets. At least with the Leaf motor the procedure was proven to work.
What you mean is that you get additional torque by adding negative direct current to an existing quadrature current. This will create reluctance torque in addition to magnetic torque.
I'm not a full IPM expert though, just self taught.

Johannes would you split your pin swapping settings in code and make three different options/parameters? I think it would offer more choice for further designs.

You can. It's a bit field
SWAP_CURRENTS = 1
SWAP_RESOLVER = 2,
SWAP_PWM = 4
So e.g. "set pinswap 5" would swap PWM and currents.

[arber333]

You can. It's a bit field
SWAP_CURRENTS = 1
SWAP_RESOLVER = 2,
SWAP_PWM = 4
So e.g. "set pinswap 5" would swap PWM and currents.

Ok, i have it set to 3 and interface shows "CURRENT12".
If i set "pinswap 5" i get "NONE" field inside wifi interface.
What if i would "set pinswap 7", so does that mean i swapped all of the above???

Can you draw a table in wiki please...

[slow67]

You can. It's a bit field
SWAP_CURRENTS = 1
SWAP_RESOLVER = 2,
SWAP_PWM = 4
So e.g. "set pinswap 5" would swap PWM and currents.

Ok, i have it set to 3 and interface shows "CURRENT12".
If i set "pinswap 5" i get "NONE" field inside wifi interface.
What if i would "set pinswap 7", so does that mean i swapped all of the above???

Can you draw a table in wiki please...

Its a 3 bit Binary field. You add from right to left.
PWM------Res-----Cur
0 or 4----0 or 2----0 or 1

In binary it looks like this:
PWM Res Cur
0 or 1 0 or 1 0 or 1

So that results in this table:
Binary Decimal Result
001 = 1 Swap Currents ony
010 = 2 Swap Resolver only
011 = 3 Swap Resolver and Currents
100 = 4 Swap PWM only
101 = 5 Swap PWM and Currents
110 = 6 Swap PWM and Resolver
111 = 7 Swap PWM and Resolver and Currents

Hopefully this helps.

[johu]

Yes, thank you The web interface doesn't fully support this so once you set 2 of the bits it'll display "none"

[arber333]

Yes, thank you The web interface doesn't fully support this so once you set 2 of the bits it'll display "none"

Ok i understand now.
So i will try giving it a 1pt of "manualid" before giving it "manualiq".

thanks

[johu]

Thought I'd post this here:

Well resolver circuit works just fine i see.
However can you elaborate Johannes on the choise of C4 100nF capacitor in early circuit later it became 330nF and why did you decide to use 22nF wiith 10K resistor later on rev 3 board?
I tested 100nF and 330nF and they both work! Should i rather use 22nF with 10K?

C4 (in the very first schematic) is just a DC decoupling cap so the amplifier input sees a plain AC sine wave. I chose 22nF for part consolidation. Rev 3 board uses a different amplifier with higher gain so I adjusted the low pass filter attenuation accordingly. With the LM386 the old values will work.

[arber333]

Thought I'd post this here:

Well resolver circuit works just fine i see.
However can you elaborate Johannes on the choise of C4 100nF capacitor in early circuit later it became 330nF and why did you decide to use 22nF wiith 10K resistor later on rev 3 board?
I tested 100nF and 330nF and they both work! Should i rather use 22nF with 10K?

C4 (in the very first schematic) is just a DC decoupling cap so the amplifier input sees a plain AC sine wave. I chose 22nF for part consolidation. Rev 3 board uses a different amplifier with higher gain so I adjusted the low pass filter attenuation accordingly. With the LM386 the old values will work.

Aha, but is there any benefit in using 100nF or 330nF on the old schematic with rev.2 main board? Which one is better?

tnx

[kiwifiat]

Given that IPM's produce torque from Id it seems to me that the recommended procedure for finding syncofs will yield an incorrect result. If the motor was an SPM then it would be correct since Id produces no torque. I would keep adjusting syncofs until the motor runs correctly in either direction. Maybe johu can chime in?

No there is neither reluctance nor magnetic torque if the field is perfectly aligned with the magnets. At least with the Leaf motor the procedure was proven to work.
What you mean is that you get additional torque by adding negative direct current to an existing quadrature current. This will create reluctance torque in addition to magnetic torque.
I'm not a full IPM expert though, just self taught.

Johannes would you split your pin swapping settings in code and make three different options/parameters? I think it would offer more choice for further designs.

You can. It's a bit field
SWAP_CURRENTS = 1
SWAP_RESOLVER = 2,
SWAP_PWM = 4
So e.g. "set pinswap 5" would swap PWM and currents.

Agreed there is no rotor rotation when there is zero torque generated. My point is that in the case of an IPM that is not necessarily when the stator field is perfectly aligned with the magnets. A number of reports from Oak Ridge Labs in the US clearly show that the optimum angle for torque production in IPM motors changes with current magnitude and this is due to reluctance torque not the the torque due to the permanent magnets. The implication of this is that the actual stator angle in which no torque is produced must also move with stator current magnitude. Whether or not this important is a moot point but in Arber's case it would seem that the motor runs ok in one direction and badly in the other which implies that the value for syncofs is incorrect. Can you explain any other reason for the observed behavior in arber's case e.g. are there any settings other the syncofs that would cause this? And the same here, not claiming to be an expert. Funny thing is else where when I quote Doctoral qualified experts in the field of motor design I get told they are all idiots