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Weird Inductance measurement

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a.dahhak
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Posts: 17
Weird Inductance measurement

Hi guys,

I have an inductance measurement issue with my motor, It doesn't allow me to use HFI.

When I use a ready to run motor from T-motor everything seems fine, but when I try to mount my own motor (stator and rotor hooping), my measured inductance is different from a Dcy to another (picture below)

My motor runs fine at no load, but whenever there is a load it's struggling. Any help please ?

plot_hfi.PNG

indc_measure.PNG

marc426
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Joined: 2018-02-14 14:38
Posts: 13

Hi Everyone,

I'm also working on this very project.

Any leads as to why HFI seems to be completely wrong on this even though the Ld/Lq difference is quite high (which AFAIK is the criteria for a good HFI position estimation)?

We're using an official VESC6 so we're not worried of a hardware problem...

Best,

 

Marc

alexshen2012
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I met exactly the same question, the inductance result shows quite different each time measured. So, have you find the reason? 

BR,
Alex

e-biker
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Joined: 2017-09-11 10:16
Posts: 52

Hi,

I'm getting similar results, while resistance is pretty stable between measurements, inductance is jumping a lot. HFI isn't working as well, despite big lq-ld difference. Tried changing filtration in hardware, increasing sample number in measurements with no luck for better results.

Measurements with older firmware (3.62) is really stable, so i doubt its hardware issue. Hardware is custom, based on HW60mk1.

Have tested few different motors (QS3T, MXUS) and results are the same. Let me know if someone finds a solution.

Martin.

masifsr
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Joined: 2022-01-28 08:12
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Hi,

Did you guys manage to resolve this in anyway. Facing a similar issue here with HW410 and firmware (5.03)

MohammadAsif

alexshen2012
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Up

Anyone who find the solution?

BR,
Alex

Gatze
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Joined: 2018-02-03 18:06
Posts: 55

Above is spam, but I also have the same problem, despite the fact it should be quite doable with my hub motor.

emntz
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Joined: 2023-09-04 22:22
Posts: 4

Same problem here, using a motor that has a significant load from the attached bearing and cannot get a consistent inductance measurement or any meaningful information from HFI plotting.

Elizabeth Mountz