SimpleFOC power distribution

hardware support
1

Hello all, first I am very new to SimpleFOC. I have a question about power and a little nervous as this is my first high power project. The goal is safety as well as to make sure there are no issues with electrical noise etc. Attached is a schematic diagram of how I think things should be powered. What complicates matters is that I am also driving some PWM hobby servos in my project along with one BLDC gimbal motor. Im wondering if this is the correct way to power my project .

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Components:

Power supply: Laptop power supply (20v) with a standard barrel jack connector. The barrel jack is connected to a panel mount female connector.

Microcontroller: Teency 4

servo motor driver: (5v-10v) Amazon.com: Teyleten Robot PCA9685 16 Channel 12 bit PWM Servo Motor Driver I2C IIC Module for MG90S SG90 MG995 Compatible with Arduino Raspberry Pi (2pcs) : Electronics

Buck boost converter:
https://www.amazon.com/gp/product/B07NTXSJHB/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Power distribution terminal:
https://www.amazon.com/gp/product/B09D3BV22M/ref=ewc_pr_img_2?smid=A2OVMUS055KMW5&psc=1

DC Panel mount:
https://www.amazon.com/gp/product/B08SJM2G52/ref=ewc_pr_img_1?smid=A1M1ZTG5RRMU82&psc=1

BLDC motor:
https://www.aliexpress.us/item/3256805959161480.html?spm=a2g0o.order_list.order_list_main.15.43191802lvFspL&gatewayAdapt=glo2usa

BLDC motor controller: SimpleFOC.

2
  1. The PWM Servo Driver has a Vcc input pin for powering the board electronics, and a V+ for powering the servos. You are not showing what goes onto V+. I strongly advise against using the 5V from the buck converter for V+, since the servo motors will inject noise back into the 5V supply circuit.
  • Ideally you should use a separate high-current buck converter to supply the servo driver V+ pin. Add up the stall current of all the servo motors, the buck converter needs to have a current rating of a significant fraction of that.
  1. Your buck boost converter seems to want a minimum input of 5V to output a stable 5V. However, whenever the motor(s) draw a sudden high load, the voltage from the main 20V power supply could/will momentarily drop below 5V. The Teensy and Servo driver board will have brown-outs/resets.

The goal should be to not connect any mechanical/high-power/transient load to the 5V voltage regulator, it should be reserved only for pcb electronics that need a stable power supply (eg Teensy, PCA9885).