looking for programmable sine controller with flux weakening under $60 USD

[pwd]

I'm on the hunt for a small (6fet sized) programmable controller sinewave controller that can do regen braking and flux/field weakening for under $60 USD. I'm planning on using 25A peak battery current and 70A peak phase current.

I've looked at greentime and KT controller but it seems that they do not have flux weakening.

So far this controller is the only one I can find that *might* work:
https://www.aliexpress.com/item/32945185610.html?spm=2114.12010612.8148356.60.6fcc1fc4izMiJv

It appears to be a Xie Chang style KH6 controller which can *possibly* be programmed with Keywin or XPD software if I add the programming leads to the board. I have read that these Xie Chang controllers are a fairly dated design though.


Are there any other controllers that might have what I'm looking for?

 

[amberwolf]

First, what specifically do you require FW for? Maybe there is another way to do what you want that doesn't require it.


If you want field/flux weakening, then it's not just sinewave you're after--you need FOC (field oriented control). FOC controllers will need to be setup for the specific motor they are running (some have autotune setups with manual finetuning, and some must be completely manually done).

Most cheap sinewave controllers don't do FOC, they only use a lookup table for the waveform, and dont' have any motor parameters to setup.

I'm not aware of any XC type controllers that do FOC, just the lookup table sinewave stuff.

Can't think of any FOC controllers that are within your budget.

I think some of the VESC controllers do FOC (maybe all of them); there are variations here on ES for various power levels.

Powervelocity might; you'd have to check the sale threads.

Nucular should.

Phaserunner/Baserunner does. (as do the ASI BAC controllers they are based on)

The Lebowski brain can do this, but you have to build the controller, and the prebuilt brain available from kiwifiat costs half again as much as your budget, not including a powerstage. (you could hack the powerstage of an old controller you have laying around to accept the brain, but would also need to add three phase current sensors, which will also cost a fair bit). It's often cheaper to get an old EV controller and use it's powerstage, like I'm doing in the HI-Lebowski thread, but this will be large/bulky/heavy and is likely way more than you need.

 

[pwd]

Thanks for the reply amberwolf.

I'm looking for flux weakening so that I can economically get a few more rpms out of a Magic Pie 4 without increasing pack voltage or buying a different motor with a higher rpm/volt. Perhaps "flux weakening" isn't the right term that I should be using. I have sometimes seen it referred to as "over speed" or "120%" etc...

I know that the EB3XX (sqaure wave from em3ev etc...) and KH6XX (simulated sine wave) Xie Chang (Infineon clone) controllers will do over speed / flux weakening using the keywin or XPD programming software. I have one of each controller and it works OK at 120% speed on the EB3XX or with flux weakening set on the KH6XX .

I looked into the Powervelocity, Nucular and Phaserunner/Baserunner controllers but they are out of budget / more than I need as you mentioned. I will have to look into VESC though.

Cheers

 

[amberwolf]

I'm looking for flux weakening so that I can economically get a few more rpms out of a Magic Pie 4 without increasing pack voltage or buying a different motor with a higher rpm/volt.

Then FW is capable of doing that, at the cost of higher power usage.

Perhaps "flux weakening" isn't the right term that I should be using. I have sometimes seen it referred to as "over speed" or "120%" etc...

Well, FW isn't the same thing, and doesn't work the same way, though both might acheive the same end.

Some controllers may not actually ever give 100% PWM duty cycle to the phases, under normal conditions, and the three-speed switch may be programmable (or already set) to allow one of the settings to do this. That's more or less what the 120%/etc settings do. FW is a pretty different and more complicated mechanism; there's some threads about how it works if you're interested in the details.

So if you already have a controller that does the 120%, you can test the theory on your MP4, before buying something new that may not do what you want.

FWIW, some of the MP controllers are programmable, but that might not be until the MP5 version. You could check with Gary(?) at Goldenmotor.ca and see if he knows. Even if the MP4 is, it might not have the option you're after.


Another thing you could try is to increase the actual throttle signal voltage a little bit, and see if it increases the wheel speed. IF you have a 5k-10kohm potentiometer, you can wire it up in place of the throttle, and test offground to see if the wheel speed increases from what it was with the throttle. It probably wont' work, but it's worth a shot before changing out the controller.

 

[stancecoke]

FW is a pretty different and more complicated mechanism;

?! Field weakening is no mystery at all and can be done with lookup-table based sinusodial commutation, of course.
You just have to increase the advance angle. I think Casainho has implemented it in the TSDZ2 firmware, where no "classical" FOC is used. I made a suggestion, how to use it with the Kunteng Firmware already, but nobody has done it so far, I think.

https://endless-sphere.com/forums/viewtopic.php?f=30&t=87870&p=1555068&hilit=weakening#p1555068

regards
stancecoke

 

[amberwolf]

?! Field weakening is no mystery at all and can be done with lookup-table based sinusodial commutation, of course.
You just have to increase the advance angle.

I did not realize that. Though I still doubt the typical common controller of that type has it implemented from the factory, I guess that opens up the possibility of it.

 

[pwd]

Thanks for the info so far folks.


The VESC projects look fantastic! Unfortunately, it seems that 13S pack voltage is their limit. I'm running 14S.

So if you already have a controller that does the 120%, you can test the theory on your MP4, before buying something new that may not do what you want.

FWIW, some of the MP controllers are programmable, but that might not be until the MP5 version. You could check with Gary(?) at Goldenmotor.ca and see if he knows. Even if the MP4 is, it might not have the option you're after.

Another thing you could try is to increase the actual throttle signal voltage a little bit, and see if it increases the wheel speed. IF you have a 5k-10kohm potentiometer, you can wire it up in place of the throttle, and test offground to see if the wheel speed increases from what it was with the throttle. It probably wont' work, but it's worth a shot before changing out the controller.

Using my existing EB312 controller sounds like a good place to start after I try the 5k-10kohm potentiometer. I've tinkered with the Magic Pie software over the years and actually everything from the MP2 onward is programmable to some extent. There is no such feature to allow more rpms etc.. though and the settings are a bit limited for what I need. Regen braking doesn't work until the pack voltage drops to about 56V (not adjustable) which is another reason I'm ready to ditch the stock controller.

I made a suggestion, how to use it with the Kunteng Firmware already, but nobody has done it so far, I think.

viewtopic.php?f=30&t=87870&p=1555068&hi ... g#p1555068

regards
stancecoke

I really hope someone is willing to run with your suggestion on how to implement flux weakening on the Kunteng Firmware. That task seems like its a bit beyond my abilities. I've read through some of that thread and they seem like an excellent value and easy to find controller.