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  1. Mihai_F

    300A bldc esc, mosfets ringing, help

    this is on high side fet-s, but not all the time, in 64 captures about 1/4 of them every now and then are like this, the rest of them are without that pulse after turnoff, could it be self turn on or what is that? i read a few suggested papers (parasitic turn on, dv/dt, ect.) and i suspect gate...
  2. Mihai_F

    300A bldc esc, mosfets ringing, help

    Well i had 2 attempts at making a complete schematic and to this day i did not finished it, i have bits an pieces here and there, i personally find it easier to work from the layout, that way i know precisely what goes where, so then i did not put any more effort in to finishing the schematic. I...
  3. Mihai_F

    300A bldc esc, mosfets ringing, help

    I saw your post on testing LM5017, from there (peters thread) i got inspired, and did my test on LM5017, the layout is nice and tight, so my 4V overshoot and undershoot might be measurement artifacts. The gate resistor, i tryed a few values, 15R was fast and nice but ringing was high, 100R (as...
  4. Mihai_F

    300A bldc esc, mosfets ringing, help

    This last measurement was made directly on FET legs close to case with tip of the probe and the short coiled gnd aroud the tip, that is not easy to make and grate care must be taken not to short circuit FET legs to the busbars or to themselves, that will be even more difficult in the open air...
  5. Mihai_F

    300A bldc esc, mosfets ringing, help

    I tried this morning with snubbers (4.7n+5r) on low side fet-s and 47R gate resistor, things improved big time at 10A load (compared with the first measurement in the post with no snubbers), now in the next days i'l go out put the prop on and give it load and see how it turns up, hopefully not...
  6. Mihai_F

    300A bldc esc, mosfets ringing, help

    The v1.2 had about 500ns turn off and this on the output at 75V and 130 A I think i'l stick to that speed because it worked fine in terms of overshoot and heating of the FET-s, the low freq wave was probably ringing between DC link caps and decoupling caps I'l next week try snubbers between...
  7. Mihai_F

    Delta Vs Star Connection...Pros and Cons

    https://endless-sphere.com/forums/viewtopic.php?t=86481
  8. Mihai_F

    300A bldc esc, mosfets ringing, help

    When testing the v1.2 with 4468 fets i had 6 nichicon 1000uf caps, witch had only about 11A ripple and about 6mohm esr total, and after 2 30min test when power was cycled repeatedly from 10 to 16Kw, the caps did not even get worm, now they had a lot of cooling (prop wash). V1.3 has 6 chemicon...
  9. Mihai_F

    Building a motor

    I might work saounds doable, i head some people over the internet somewere trying it, but it might be a mechanical challenge trying to fix the segments in to place, they have to be really sturdy, all the motor torque acts on them...
  10. Mihai_F

    Building a motor

    Yes, the lamination supplyer said that is non orientated grain, witch is a must for motors, the material is m330-50a
  11. Mihai_F

    Building a motor

    I forgot to mention delta winding
  12. Mihai_F

    Building a motor

    Unfortunately 0.5mm laminations, i coukd not find 0.2mm sadly, so i have 700w loss in heating the iron, the stack is 40 mm hight, hence 40x10x5 magnets, so 80 pieces per set, i only got money for 2 sets at that time, stator is 192mm diam 30 slots and 40 magnets, ABC winding scheme trapezoidal...
  13. Mihai_F

    Building a motor

    I got them cut in italy, i have to search for that complany, and it was 600 euro (in 2016) fo 2 sets preaty pricy, but for 10 sets they asked for 1000 euro... It ain't cheap, but considerind that here in europe there is a company that sells this kind of motors (bldc outrunnets) and they asked...
  14. Mihai_F

    Building a motor

    Yep the real thing, 7.7kg, 10uH, 6mohm per phase, 36kv, N45 40x10x5 magnets, stator laminations are laser custom cut.
  15. Mihai_F

    300A bldc esc, mosfets ringing, help

    I'm thinking to use polypropylene caps (i have some 1uf 250vac big ones) for decoupling or ceramics, but i'm afraid of those becose they fail with no worning and are kinda distructive, aldo pp caps are not as good as ceramics at decoupling, il try it and see.
  16. Mihai_F

    Building a motor

    Here is how : https://www.avrfreaks.net/forum/electric-propulsion-system-ppg-and-ultralights, that motor (20kw) has 60x0,5 strands tristed so they stay nice, and was decent to work with.
  17. Mihai_F

    300A bldc esc, mosfets ringing, help

    It does have hall current sensor on the positive bus. I have to wap my head aroud and figure how to make a 4 layer power board, i was to fixated on 2 layers. Those small 1uf caps, failed after a while (melted) ESC was fine, then switched to ceramics, haf 4 banks of 5x1uf in parallel, they failed...
  18. Mihai_F

    300A bldc esc, mosfets ringing, help

    For fault management, i have emurgency battery disconect, the controller is in a 1,5mm thick aluminum enclosure so plasma and fire can not get out of it (i tested it), and if FET-s go shorted the battery has enough energy (4,88Kwh 1200A continous) to vaporize them and anything in the controller...
  19. Mihai_F

    Building a motor

    The skineffect is influenced by base PWM also, not just the erpm (motor frequency), atleast if motor si not running at WOT, the winding will se that PWM frequency, hence high pitch sound from motor when base PWM is under 14khz (depending on motor and human ears). 0,51mm copper can go up to about...
  20. Mihai_F

    Building a motor

    Be careful with 3d printed rotor, if it is from plastic might not be strong enough and deform from magnets force (all those magnests pulling the iron core add up), or worst if spinning to fast might fly apart at those diameter you have there. I suggest you use thinner copper wire strands somting...
  21. Mihai_F

    300A bldc esc, mosfets ringing, help

    Let's clear a few things first: 1. Just now i realized that i made a mistake on typing the FET-s part number, it is IRF150P220, sorry for that mistake, i will edit the post. In the avrfreaks link that i shared in the first post, there is the corect part. 2. I did read all the post you mentioned...
  22. Mihai_F

    300A bldc esc, mosfets ringing, help

    Well i know that the measurements are not 100% acurate, but v1.2 with same layout and IRFP4468 fets worked with 200 amps at 84v, and now with IRF150P220 fets the ringing is way bigger, and i can not go past 50 amps becouse fets blow up, and yes they did blow up, all 18, preaty expensive. I think...
  23. Mihai_F

    300A bldc esc, mosfets ringing, help

    Hello community, i have been working on a big project for the past 6 years , https://www.avrfreaks.net/forum/electric-propulsion-system-ppg-and-ultralights, you can find it here for details, i can post it here also if there is interest. The main problem that i have is that low side FET-s...
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