SPEED CONTROL 20A TRACKs width  - Page 1
Forum section: electronics / projects

author: amirkargar110
author_rank: Contributor
timestamp: September 07, 2017, 01:39:55 pm
content: HELLOI want to make a 20A speed control for my Quadcoupter. when I calculate the track width for 20A current, the width should be at least 21mm or if i use double side track the width should be 9mm on each side.these tracks makes my speed control very big and heavy.whereas the commercial speed controls is very small and light.are they 4 layers or 2 layers?what should I do for my design to be small and light?if somebody has open source PCB of it introduce me please.and another question is, the "+" track width should be as wide as the "-" (or GND) width? if not what is the proportional between them(power and ground track width)?

author: FreddyVictor
author_rank: Regular Contributor
timestamp: September 07, 2017, 04:21:03 pm
content: Is there any reason why you want to design/make your own ESC ? just seems alot of work for little benefit over existing cheap Chinese designsWhat uC (control processor) and software are you going to use, or are you going to write your own ?ESC's are actually quite complex, and really not for the beginnerShould you manage to make one, you'll need to do alot of testing to make sure your ESC doesn't fail in-flight causing expensive damage to your Quadit only needs a single failure ...A quick search on the internet showshttps://github.com/bluerobotics/BlueESC- other similar projects linked on that page

author: krish2487
author_rank: Frequent Contributor
timestamp: September 08, 2017, 11:02:38 am
content: First,Dont Shout!It is common forum etiquette. ALL CAPS indicate shouting. Please refrain from doing do.Second,as freddy pointed out unless you have a very specific reason for rolling your own try and stick with a COTS ESC.Third,looking at the query you have posted, I would guess you have relatively low to no experience in1. Power electronics2. PCB layout and basics.Code:and another question is, the "+" track width should be as wide as the "-" (or GND) width? if not what is the proportional between them(power and ground track width)?No no no!! if you have doubts like this, please go back to the fundamentals. Read AoE and then read it again till you understand the basics of power delivery right.Heck till you understand the basics of Ohms law first.21 mm or 9mm is very very small and manageable. If a PCB has to carry a finite amount of current at a rated voltage and meet isolation requirements, they have to work within the limits of physics. No ESC worth its salt can violate it. I am not saying bad designs dont exist, but to meet a requirement there are two ways of doing it - right and wrong.Often in the scheme of doing things right - functionality takes a higher priority over "big and heavy". The aesthetics, form factor, shape, size and finish matter but they still have to obey the laws of physics.Please read up and then read more on fundamentals. Half understanding will only put you and others around in danger.

author: fcb
author_rank: Super Contributor
timestamp: September 08, 2017, 05:27:38 pm
content: Re-run your calculation. Change the acceptable temperature rise - it's not in a 70C environment, it's likely to be outside with tons of air-flow?Increase your copper thickness from 1oz to 2oz or thicker. Post your design! What thickness can you cope with - what's the dissipation/rise?Experiment!

author: Siwastaja
author_rank: Super Contributor
timestamp: September 08, 2017, 05:39:20 pm
content: Inverter design with BLDC control is not trivial. Track width calculation should be the least of your concerns. Things like proper layout, switching performance, EMI, and control algorithms will prove orders of magnitude more difficult.By googling Open source ESC or open source BLDC, you'll find several projects that will help to verify what you are designing.