Hi dear friends

I would like to work on a project whose title is design and implementation of a Microcontroller-based relays. So, Any Idea How to Start?


At the begining I will use Hi_level language 'Matlab" in order to simulate the algorithm.

A method called " Four-Sample Method" should be used to identify the signal “basically taking one sample each ¼ of the period (T=1/f=1/60) and using these samples to calculate the RMS value of the current to be monitored”. After getting the RMS value, it is to use another algorithm to implement the relaying decision part of the program. It is required to see the current value continuously in the normal condition and then if fault occurs.


We are working on it as a group but no matter to share the ideas here.

 

I would start with picking a controller.

Did your team have one in mind? Obviously you are going to want a uC with Analog To Digital Converter on board of a high enough resolution to get accurate readings of the desired event.

In your case, an over current event (it seems).

Are you using a hall sensor to detect the current or another method?

 

Good Afernoon/Morning Retched

I appreciate your response, we have just started searching about a suitable u.controller.
Actually, we will have a meeting at the middle of the coming week to see our starting step which includes surveys and M.C acquiring.
Do you have any idea about representing Four-Sample Method via Matlab?

Keep in touch dear Retched.

 

Mat-Lab is a new beast to me. I have less than a month under my belt.

As for sampling methods, mat-lab+simulink have the ability to emulate/simulate PIC processors. You can incorporate the algorithm directly into the PIC code and matlab will follow the instructions.

The 4 sample average is a standard sampling method.

Taking the time to be sampled and dividing by 5.
That gives you 4 periods to sample and gives time to move data before the next sampling session begins.

If you want to sample over 5 minutes, you would record the current at the trailing clock edge leaving the first minute, second minute, third and forth,
During the 5th second you can calculate the average and decide to re-sample the next 5 seconds or activate the cut-off relay (or any other action)

I guess I should ask, is this a university or school assignment? Is matlab required in this project?

 

Hi Retched

I will take care of what you said. I'm more that happy to try your suggestions.
Realy, I need your advices in order to be able to continue the project.

Ya, it is a university project and matlab is just first step then we will go directly to C++ or assembly.

Indeed I will have a couple of questions in the next few days, so how can I contact you. Is this path okay, or it is better to select another way.

 

Sure, just post the questions. That way, if there is anything I dont know, others can answer.

Also, others may have better ideas, or better ways of doing what you want. Posting in the forum allows that to happen.

Also, there will be other people who have the same problem as you, and they will be able to use this thread to get help later. 2 weeks, 2 months, 2 years from now.