Search found 330 matches

by marcos
May 07 2020 7:53am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

I think what Arlo1 does here is not what I do... I have a 45 degree rotation in the error signals of Id and Iq, this is fundamentally not the same as a 45 degree rotation in the resolver output... with the rotation in the resolver signal you will not be FOC anymore as you also rotate the wanted Id ...
by marcos
Mar 17 2020 6:22pm
Forum: Motor Technology
Topic: True FOC: definition and examples
Replies: 53
Views: 2656

Re: True FOC: definition and examples

I don't think any shunt/sensor configuration is more "true" as long as the controller is working in the two axis rotor frame. I assume that "two axis rotor frame" concept is related to calculating Quadrature/Torque (Iq) current vs Flux/Direct (Id) current via Clark/Park-transformations ? Yes, and 2...
by marcos
Mar 17 2020 9:24am
Forum: Motor Technology
Topic: True FOC: definition and examples
Replies: 53
Views: 2656

Re: True FOC: definition and examples

In my mind, field oriented control does the motor control in the rotor frame. So if the torque control is based on setting an iq and id current, that's FOC. iq/id are the currents in the rotor reference frame. So if you are standing in the rotating rotor, you see DC currents instead of sinewaves. ht...
by marcos
Mar 07 2020 6:01pm
Forum: Motor Technology
Topic: Does adding more cap to the DC bus on a controller help? Look in here for the answer.
Replies: 10
Views: 785

Re: Does adding more cap to the DC bus on a controller help? Look in here for the answer.

Back of the envelope calcs sound reasonable, thanks. Looks like a loose power input connector shouldn't make much damage. Something to think about is that when you have a battery disconnect event, it could be a short somewhere that is tripping a fuse or contactor, and they trip at currents quite hig...
by marcos
Mar 07 2020 12:03pm
Forum: Motor Technology
Topic: Does adding more cap to the DC bus on a controller help? Look in here for the answer.
Replies: 10
Views: 785

Re: Does adding more cap to the DC bus on a controller help? Look in here for the answer.

Does a large inductance between battery and DC link change the voltage situation?
For example during normal operation and also when the BMS disconnects the battery at peak current.
by marcos
Mar 05 2020 4:01pm
Forum: Motor Technology
Topic: What's so bad about low impedence?
Replies: 30
Views: 1535

Re: What's so bad about low impedence?

peters wrote:
Mar 05 2020 5:16am
The problem with low inductance is that the phase ripple current within a PWM cycle can be too high, because the BEMF and the battery voltage is different and the inductance is between them, and may exceed an overcurrent trip threshold (or something else..).
^exactly this
by marcos
Feb 19 2020 12:58am
Forum: Motor Technology
Topic: Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)
Replies: 48
Views: 7108

Re: Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (Prototyped. Materials have arrived for a test batch)

Distilled water is orders of magnitude less conductive than tap water. If a powerful fan doesnt cut it, or if the dyno doesnt fit in a fridge I would give pure water a try. Mineral oil isn't as great moving heat away, and its messy. Maybe rub a bit the motor with alcohol to make it extra clean so it...
by marcos
Feb 01 2020 12:25pm
Forum: Motor Technology
Topic: Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)
Replies: 48
Views: 7108

Re: Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (Prototyped. Materials have arrived for a test batch)

During double pulse test you want to look at the gate that is kept always off. Here you can see how the gate turn on looks like. Also, when you make RgOFF larger (slower turn off, less overshoot) you are making miller turn on worse because driver loses strength to keep the gate at 0V, so its not a s...
by marcos
Jan 31 2020 10:41pm
Forum: Motor Technology
Topic: Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)
Replies: 48
Views: 7108

Re: Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (Prototyped. Materials have arrived for a test batch)

Slowing down the switching won't hurt much if you don't use very high switching freq like 25+kHz. High end VESCs often switch at 25 or 30khz because the observer works better with more sampling per second, but you can halve that by sampling on both V4 and V7. Its important to take a look at the gate...
by marcos
Jan 21 2020 12:59pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

Hello, someone has tested FF600R06ME3 from aliexpress?, prices are 1/4 the price at mouser! about 40€, is it possible? Most likely counterfeit, and most likely its not worth the risk if a total fire costs you more that what you saved in those IGBTs. On other news, we got merged some features for be...
by marcos
Jan 11 2020 4:31pm
Forum: Motor Technology
Topic: Serious FOCer (84V VESC 6 based controller)
Replies: 262
Views: 36177

Re: Serious FOCer (84V VESC 6 based controller)

Instant kills are usually caused by overvoltage or shoot through events, both can be seen in a double pulse test. Before performing any high power test your gate drive should be tuned based on your double pulse test results. If the long gate traces are too susceptible you will have to reduce the gat...
by marcos
Dec 14 2019 8:38am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

Hey marcos what is status of MTPA and flux weakning. I want to test switched reluctance IPM motor on this controller. That branch is quite behind the latest master branch, and requires you to build both vesc firmware and vesc tool in order to have the features. FW still lacks a safety feature that ...
by marcos
Dec 07 2019 10:51pm
Forum: Motor Technology
Topic: Max erpm and field wakening
Replies: 11
Views: 1579

Re: Max erpm and field wakening

Different conceps there * Max eRPM refers to the base frequency of the motor drive. If controller states 60kerpm then its PWM can generate 1kHz sinewaves while keeping the motor under control. * Max switching freq refers to the transistor switching freq, it could be 15, 18, 21kHz for example. Note h...
by marcos
Nov 22 2019 10:15am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

The Axiom part starts at 13:15 in the video. Soooo good to see you together on the stage, deep respect and congrats! The whole thing was an awesome meetup, and it was great to have the chance to finally have a team meeting, here are 4 glasses for maxi that didn't make it. 20191116_134321.jpg Btw I ...
by marcos
Nov 03 2019 10:26pm
Forum: Motor Technology
Topic: Sensorless From Standstill (SFS) explained
Replies: 24
Views: 3310

Re: Sensorless From Standstill (SFS) explained

That's a very awesome and valuable contribution Lebowski, thanks!! I'm not sure the STM32F4 can handle this non-center-alignement phase shift, I think it requires the coordination of many many timers. In any case, I sent the tip to benjamin vedder, we was considering this kind of signal injection so...
by marcos
Oct 28 2019 7:22am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

I thought VESC already supports multiple VESC with multiple motors over CAN? Is that not what Vedder describes as Arrays of VESCs or are we limited to an array of two VESCs only in Version 6? How do they implement e.g. 4wd skateboard with 4 VESC & 4 Motors? Are they simply running 4 motors off two ...
by marcos
Oct 22 2019 9:31am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

Does this controller have the ability to daisy chain, so if you had 4 motors, and 4 controllers, you could connect the throttle to one acting as the master controller, which would send data to the other 3? Everything is possible. The only limit is your imagination and your time. And the flash memor...
by marcos
Oct 16 2019 4:54pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

I watched one of Arlin's videos on the Axiom he's using in his Honda and he suggests there might be Torque Vectoring possible/coming? I assume Traction Control is already possible through VESC software anyway, but are there plans for Torque Vectoring to be available or is Arlin developing this just...
by marcos
Sep 30 2019 5:14pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

would like to ask also any update on the pcb that would let us adapt let say already built powerstage from some inverter to the axiom logic board? No updates in that regard. I have the kicad files ready to upload, they didn't change since we defined the general layout and pinout. I just never made ...
by marcos
Sep 30 2019 9:48am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

Hello MArcos, could you please provide some updates on what is going on with Axiom? any updates on ACIM support? Hi Shaggy, These last few days we were making the last strides in the hackaday contest, it closes today. One of the requirements is to make a video so we are spending the bootstrapping s...
by marcos
Sep 25 2019 5:08am
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

Yes! Right after we finish validation and we have an enclosure made.
by marcos
Sep 10 2019 4:39pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

Into the finals!

https://prize.supplyframe.com

Wooot! Happy happy!

Now back to work. Dang SPI driver speedup is taking me ages to get working.
by marcos
Sep 09 2019 8:57pm
Forum: Motor Technology
Topic: most power dense reliable esc available today
Replies: 4
Views: 422

Re: most power dense reliable esc available today

An old leaf motor can reach 200kw for a few seconds.
by marcos
Sep 09 2019 4:55pm
Forum: Motor Technology
Topic: most power dense reliable esc available today
Replies: 4
Views: 422

Re: most power dense reliable esc available today

It would be useful to also specify the current/voltage range you need. There are compact 200kW drives out there, but its worthless if you need 10kW.
by marcos
Sep 09 2019 4:40pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 423
Views: 93384

Re: Axiom: a 100kW+ motor controller

@marcos good to see this released! One question though. Why use a digital isolator + non-isolated CAN transceiver instead of an isolated CAN transceiver like the ISO1042? Main reason is sourceability, if that is a word. I prefer to avoid part obsolescence and keep supply chain flexible. ISO1050 and...