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  1. Mihai_F

    FOC questions

    Well the duty mode was just incrementing/decrementing Vq thru a time constant buffer (no PID). The sensored observer at startup just gives 6 angles, one for each middle sector (like 6 step commutation), but now i working on implementing to get real angles from it. I tried (sensorless after...
  2. Mihai_F

    Electric Drift Trike Build

    here are a few more photos, the development controller, a small high speed test brushless motor , and other stuff. last pic is keyway broaching on manual lathe about 100 passes (0.040 each) for a 4mm keyway, diy tool also.
  3. Mihai_F

    20Kw motor and 300A ESC (ultralight aircraft propulsion system)

    Hy there, I bought 5000mAh hobby king cells to replace the 2 dead cells from the battery. I chose the same cells again, because I have 2 packs 3s and 4s that are 9yrs old (same batch as my ultralight plane batt) and i abused the heck out of them on my rc car and plane the past 3-4 yrs they...
  4. Mihai_F

    Electric Drift Trike Build

    Hy there, I will present here my electric drift trike build, with details for mechanical and electrical parts. It all started after i decided to migrate my projects to STM32, then started to make my FOC code and controller, here is the FOC thread FOC questions So i needed a "vehicle" to test my...
  5. Mihai_F

    FOC questions

    I only plan to use sensor for start up, to know the initial angle, i did some test and it works, but i'm having trouble with sensorless switchover. It starts with halls, great torque, kinda jerky, then (at about 100rpm) transitions to sensorless witch works good, even down to verry low RPM. One...
  6. Mihai_F

    FOC questions

    That is very similar how i implemented it in my 300A EPS aircaft controller, but BLDC tarp waveform, with adaptive timing advance. There was a lot of filtering needed for checking hall input fi valid or not because of noise...lots of "PITA", in the end works nice, now i plan to migrate it to FOC.
  7. Mihai_F

    FOC questions

    Hy, thanks for you last response, that cleared the things a bit. Now, can you explain a bit the hall sensor implementation (principle) in MESC software, how do you get from hall pulses to rotor angle? I seen that you measure the time tick (pwm cycles between hall states), but i'm a bit lost in...
  8. Mihai_F

    20Kw motor and 300A ESC (ultralight aircraft propulsion system)

    the cells that would use are made by LG chem lithium NMC/ NCM712,- pouch rectangular, and will be ider individual or from vw id batt module, a pack with about 100 to 120Ah 50 to 64 kg 22 or 24s in order to have about 80-90 min flight time. I found some sources here in europe that have LG chem...
  9. Mihai_F

    20Kw motor and 300A ESC (ultralight aircraft propulsion system)

    Hi there, I managed this weekend to get one more flight (30min) out of my battery (21s left), it held 14 to 12kw for 4minutes, then 7kw for almost the rest of the flight. All monitored parameters ware in spec, and about toward the end of flight, all cells reached 3,3v to 3,4v about the same...
  10. Mihai_F

    FOC questions

    Hy guys, I have some questios regarding FOC operating modes, speed, duty, torque. So far in my implementation PID controlled the Vd comand in order to keep Id at 0. Vq directly controlled by throttle input gives duty mode. I tried Vq thru PID and it worked like torque mode, throttle input...
  11. Mihai_F

    Selling 22Kw motor

    updated prices
  12. Mihai_F

    20Kw motor and 300A ESC (ultralight aircraft propulsion system)

    A bit of an update. Battery degradation after 9years, stored at 20degC and at 3,8V/cell most of its life, it had a total of 10 cycles on it. One year ago it started to die, first 2 cells at once went to 0v over a time of 1 month (at that time i was doing batt measurements in storage once a...
  13. Mihai_F

    20Kw motor and 300A ESC (ultralight aircraft propulsion system)

    Hello Guys! Due to some personal reasons i have to sell my project, all its contents. https://endless-sphere.com/sphere/threads/selling-22kw-motor.123123/
  14. Mihai_F

    Selling 22Kw motor

    Hello Guys! Due to some personal reasons i have to sell my project, all its contents. This is my project: 20Kw motor and 300A ESC (ultralight aircraft propulsion system) Here is what i'm asking for my propulsion system, detailed description is in the upper link on the first pages. BLDC...
  15. Mihai_F

    Motor Winding Calculations & Cooling Design

    Here i found a good explanation for some winding "type" decisions. These guys know they're business well. Also a very good explanation of skin effect in conductors. Enjoy.
  16. Mihai_F

    Motor Winding Calculations & Cooling Design

    I have done some studying regarding cooling options for electric motors, especially liquid cooling, and i stumbled on Direct Winding Heat eXchanger "DWHX" (it may be trade mark....). Basically there is a T or I shaped heat exchanger (liquid cooled) between the windings of the stator teeth, and...
  17. Mihai_F

    Is a 50KW Out Runner motor any good for a retro street motorcycle?

    The motor in the first link, they say 50kw, i would like to see how many seconds that motor lasts at 50Kw, i mean i have a monster motor at 216mm diameter, 8kg, big beefy coils, and at 18kw in 2 minutes hits 80degC at 25degC ambient. So what the heck? 50Kw at 154mm and barely 6kg, is max instant...
  18. Mihai_F

    Motor Winding Calculations & Cooling Design

    After a week of reading and studying(+500pages), i got some answers. I found a really good book(by pure luck) that discuses PMSM to, not just Induction motors, it's name is Design of Rotating Electrical Machines, and from multiple sources of information, i got some knowledge to do the...
  19. Mihai_F

    Motor Winding Calculations & Cooling Design

    Hello guys, I have been searching the internet for a log while, about formulas and books how to calculate the windings of a 3 phase motor, i.e. nr of turns, wire thickness etc. I found some good theory books, some good sites explaining stuff, but haven't found an actual practical example with...
  20. Mihai_F

    FOC questions

    Hy i'm back with progress, Big update, i transformed the code to a more readable and maintainable way, with structs, pointers and all that stuff (like mesc). I decided to do it now while it is "simple" and not "many" lines of code, because later would be much harder to do it... I kept playing...
  21. Mihai_F

    FOC questions

    Hy i'm back with more progress, i'v been testing on 3 different motors and speeds, testing sensorless staring and running algorithms. (i did not wand to just copy the mesc code, i preferred to just learn from it). So, at 0 throttle when motor in breaking, if i rotate the rotor (even slowly) I...
  22. Mihai_F

    FOC questions

    hy, I had an ideea with regard to flux observer, it started when i questioned the "add to itself" - integration "flux_a = flux_a + (Vab.a - m.R * Iab.a)* pwm_period- m.L_D * (Iab.a - Ia_last)" pseudocode from mesc The integral integrates, and if there are steady states or very small changes...
  23. Mihai_F

    FOC questions

    hy, i got success spinning the motor in sensorless FOC using the flux observer algorithm (although manually started :D ) and no PI yet, just manually playing with Iq and Id inputs, that is so cool though, seeing their effect. i still have some questions regarding flux observer: 1. in the...
  24. Mihai_F

    FOC questions

    here is the explanation of what i mean by that. Implement αβ0 to dq0 transform - Simulink
  25. Mihai_F

    FOC questions

    I have some questions, regarding mesc firmware: 1. i understanded that the phase voltages are "processed" only in tracking mode when the H bridges are disabled, and flux observer is "processed" at each pwm cycle, inside the calculations of flux observer is needed the phase voltages to calculate...
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