Endless Sphere

Do you reckon your 26650 modules would work with 26800 if the print was scaled?

I spoke with technician, and he sad that cause of failure -is broken bearing. Because of it, a heavy load on the gears began I haven't seen your broken gearbox up close but the bearings in planetary gearboxes should be very reliably since the forces are balanced. Is your controller very rough and j...

Very cool! Is the field weakening firmware based on the Power Designs experimental branch of the VESC firmware? The field weakening current is calculated based on motor parameters. I think their strategy was to adjust Id to try and maintain modulation at the maximum. I did use their way of adding a...

Tweaked the fw a bit so that Iq decreases smoothly and there isn't that odd surge in power at high speed. Motor power and voltage are now more constant in the field weakening region.

BESC really does seem like the closest thing to what you are after. I had a look at the github and it looks pretty good, just some small fixes that need to be added.

Going over 100v will always add to cost.

The point in the curve where battery current suddenly drops off and motor voltage sharply increases, corresponds to a spike in Id. But it's POSITIVE! It looks like field weakening is going wrong.

Your understanding seems to be correct. For our EVs we don't tend to look at it in terms of power factor, but in terms of motor back emf. In case 2, on the other hand, going up a steep hill, I am wondering if the load becomes more resistive and the current lag becomes less, bringing the power factor...

I have seen various chinese motors with 12 stator teeth and 8 magnets (just like bbshd). The winding scheme is usually ABCABC. Coils on the same phase wound in series.

Finally ditched the cycle analyst! For the past few years it has only been a display and I haven't actually used any of its control functions. Also managed to changed the gauges on one screen to show the D and Q axis currents so I can see what is happening with field weakening. https://i.imgur.com/q...

Are you trying to lower the kv? The windings should handle 72v as is. Easiest way forward is to simply replicate the existing turn count and wire gauge.

Wouldn't 15% faster be even faster than a square wave controller at full speed?

So the rpm of 7759 is like some magic value? Regardless of voltage? My experience was that the kv and rpm parameters didn't really affect the controller's ability to spin the motor.

Another video playing around with 10s and field weakening. Recorded during the day this time :wink:. In the previous video I had 100 or 110A battery limit but I forgot to include field weakening in the calculation so the true limit ended up being more like 150A. I fixed that in the firmware for this...

That makita pack looks nice!

I have not checked in on this thread for some months now. Great to see so many new projects and improvements.

What good cells are there in the 26650 format?

While the hardware on the bike hasn't changed since the my last update, a lot of features have been added to the vesc firmware. Since the firmware now has separate parameters for the d and q axis inductance, I thought I would try use the Ld and Lq for field weakening. The Ld, Lq, Iq and winding resi...

I intended to use 25h chain and angle grinder reducer gearbox with bewel gears (so it gave nice 90 degree turn and motor could be oriented vertically). An angle grinder gearbox ebike?! That I need to see. I might give 25H chain a try when my current sprocket wears out. The finer pitch would mean I ...

Ah I love build threads that start with chopping up a perfectly good frame

Nice work though!

Do you know if the motor is a brushed or brushless type?

If the windings have cooked rewinding the motor is an option especially if you have plenty of spare time.

I've had success with various usb to serial boards/cables. As long as they are 5v logic level (which the sabvoton should be) it should be ok. The ftdi usb to serial boards advertised for arduino on ebay are a good source.

A usb isolater is a good idea too, even though not many people bother with it.

thender wrote: ↑

May 21 2020 10:46pm

He said ASI doesn't allow end consumers of resellers credentials to log into their controllers. Ok, fine, but why are you programming controllers to do this?

Have you got a copy of the ASI pc software? A login is not required to program the controller over the serial interface.

3. I installed an aftermarket steel freehub body. No bite-in problems anymore! By far the best hub for ebikes. Not the lightest but really durable and maintenance and upgrade friendly. Yes don't forget to buy the steel freehub body with the DT star ratchet hubs. The splines on my steel freehub stil...

Note that if you have three wires going to motor windings, due to Kirchoff's Current Law, once you know the current in two of the phases, you automatically know the current in the third. My first hybrid (Honda Civic Hybrid) had only two current sensors for the three phase traction motor for that re...

ASI are pretty conservative with their ratings. I ran their bac4000 controller with the 100kv wind of the 8057. Did the auto tune and set up as per the manual and everything worked.

This whole situation has made me tear up and break down more then once, my only option left is to remove everything from the frame and attempt to fit an aftermarket mid-drive setup to the existing mounting holes Unfortunately as you've probably noticed the Bosch motor mounts are non standard and I ...

One question that's bothering the electronics noob that I am: why do vesc require that powerful drv's ? Is that a design choice ? Originally I think Benjamin wanted to reduce the component count and cost to make it easier for users to solder their own vescs from blank pcbs. The drv isn't a particul...