You are here

I Need Some Guidance With My Schematic 16s 50a

7 posts / 0 new
Last post
qwerasdf
Offline
Last seen: 9 months 2 weeks ago
VESC Free
Joined: 2021-05-03 15:14
Posts: 7
I Need Some Guidance With My Schematic 16s 50a

This is proof of concept design that im going to use later do make 16s (hopefully over 50a) Vesc for my e-bike.

imgbox: "I don't feel so good" imgbox: "I don't feel so good" imgbox: "I don't feel so good" imgbox: "I don't feel so good" imgbox: "I don't feel so good"

Questions:
Q1: Are these phase and current filters beneficial enough to have them?

Q2: How to use USB without crystal oscillator?
This A200S V3 seems to have pulled it off. Or is it just betting on luck:
https://365.altium.com/files/C6F06825-C92D-11EB-A2F6-0A0ABF5AFC1B
https://teamtriforceuk.com/a200s-v3/
https://vesc-project.com/node/339?page=8

Q3: Recommended capacitance between power fets ? (120v fets 67.2v input)

Q4: Which led pin should I use red or green?

Q5: Where is the file in which im supposed to enter all the settings like pin-out, disabling unnecessary peripherals or resistor divider ratios?

Q6: How do i set up these filter pins?

Q7: Can I use any pins for low side of the filtering capacitors? (e.g p_A_filter)

Q8: Any recommendations for connections to the STM32? (specifically the ones with "?")

Q9: So what I think the process of uploading the firmware to the empty STM32 is:
1. Download source from GitHub.
2. Edit configuration files to match my design.
3. Compile.
4. Upload using ST-LINK Utility and st link v2.
5. Set up motor configuration through USB.
Am I correct?

Current shunts are 1W resistors. I know that this is awkward but it's what I have on hand and it will do for test.
Somehow I lost my AD8418 amplifiers so I can replace them with something new. Any recommendations?

I need to keep my design as simple as possible because I will be milling it out from one-sided PCB.
(this is double-sided 0.3mm trace width) milled PCB

Elwin
Offline
Last seen: 2 months 1 week ago
VESC Free
Joined: 2021-09-30 16:41
Posts: 76

Only thing I can comment on is the current filters. You seem to have taken the values from vesc 6 mkv. These values only really work well with phase shunts, not low side shunts. Better take values from a design with low side shunts. Reason is that the low side shunt only gets current when the low side mosfet is on. When the duty cycle of the phase is low there is not enough time for your liw pass filter to settle, causing large underestimation of the current.

Ps. Check out the unofficial vesc discord, there are many people who can help you there:

https://discord.gg/63af4YGuDU

david.molony
Offline
Last seen: 7 hours 2 min ago
VESC Free
Joined: 2020-07-14 02:03
Posts: 7

1) Phase yes but not necessary if you're battling with layout on single side board. Current filters meaningless on low side shunts.

2) I'd advise you fit the crystal. It's not guaranteed to work without and probably won't at high temperature

3)1500uF+. No need for more than about 3000uF at your current levels. Include at least 20uF of ceramics really close to the FETs.

4) Copy the official hardware schematics where possible, but I think you can remap to any pins.

5) Create your own .c and .h in hwconf

6) Copy the relevant lines from the official hardware and other hardwares in the hwconf folder.

7) I believe so yes.

8) Copy the vesc 6 or 75/300 pins if possible for your layout.

9) Correct except you just type make upload, no need to use stlink utility (in Linux).

 

For low side shunts ina181a1

For phase shunts use ina240a1

qwerasdf
Offline
Last seen: 9 months 2 weeks ago
VESC Free
Joined: 2021-05-03 15:14
Posts: 7

Thank you, everyone for great advice.
I joined this discord server and it seems like people there know what they're doing.
Here is my updated schematic

added capacitors
imgbox: "imma head out"

added R25 to throttle to keep it at zero when nothing is connected
imgbox: "imma head out"

changed shunt amplifiers
imgbox: "imma head out"

selected capacitors
imgbox: "imma head out"

added input voltage divider for sensing input voltage (vcc_sense) cos Elwin knows what's up
imgbox: "imma head out"
imgbox: "imma head out"

changed some connections
imgbox: "imma head out"

qwerasdf
Offline
Last seen: 9 months 2 weeks ago
VESC Free
Joined: 2021-05-03 15:14
Posts: 7

After intense discussion on the discord server I changed current filters: imgbox go br br

qwerasdf
Offline
Last seen: 9 months 2 weeks ago
VESC Free
Joined: 2021-05-03 15:14
Posts: 7

.

mckenzie.keith
Offline
Last seen: 2 years 10 months ago
Joined: 2021-12-18 00:31
Posts: 5

I think you will need to filter the hall signals.