Generator Project: Designing a Self-Powered System with Batteries & PLC

AI Thread Summary
The discussion revolves around a thesis project to design a self-powered generator system that uses batteries and a PLC to manage power flow. The proposed system aims to allow the generator to supply energy to a household while also recharging itself by redirecting some of the generated power back to the motor. Concerns are raised about the feasibility of the design, particularly regarding power consumption and the efficiency of the transformer. Classmates suggest using supercapacitors to enhance battery performance, but doubts persist about the practicality of the entire concept, which resembles a perpetual motion machine. The conversation highlights the need for a realistic assessment of power dynamics and the potential pitfalls of the project.
jovel.happy
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I'm a graduating student of Electrical Engineering Technology (3 years) and so one of our graduating subject is thesis. We decided to make a generator that can supply the house and supply itself by giving some of the power to back to the motor which rotates it. We also included batteries and PLC.

It works like this, first the battery will power the motor, the motor will spin the generator. Some of the power will go back to the motor and the battery. Once the power from the generator goes back to the motor, using PLC, the battery will now stop supplying the motor and recharge, it will only supply back the motor when needed, using PLC. We still haven't made design for the PLC.

Homework Statement
https://scontent-a-lax.xx.fbcdn.net/hphotos-xpa1/v/t1.0-9/p417x417/1475966_881102735242274_5637216028457964277_n.jpg?oh=0fccbedf7441a6b55cb2e80a63b3e702&oe=5516453F The problem is how much power will be delivered to the load and if this design is actually possible. I have this feeling that all of the power will be consumed by the transformer. To find out how much power will go to the load, I need to know how much current will go to the transformer.

The motor will need around 85 amperes in order to operate. So that means the output current of the transformer should be around 100 amperes since some of the current will go to the battery to charge it.

The ideal transformer formula is power in equals power out.
So the output power of the transformer is (24V x 100A) = 2400W
The input power is (230V x I) = 230I
230I = 2400
I = 10 A

That means the transformer needs an input current of 10A, since it is not an ideal transformer the value is higher than 10A.


The attempt at a solution

My classmates said that we will put super capacitor in around the battery. With the help of super capacitor, the charge rate of the battery will increase and its discharge rate will decrease. But I feel even that won't help. They're just mostly laughing while I'm explaining this problem to them. They keep on saying it will work and that I don't need to worry. I'm thinking of leaving the group and join other groups instead.Another thing is the rate of charge of battery. How do I calculate the number of hours it will take to charge the battery. I've come across the formula h = (Ah of battery/A of charger) where h is the number of hours it will take to charge the battery. Does this mean that I can fully recharge a battery very very fast if it can take a large amount of current?
 
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Hi jovel.happy. Welcome to the famous Physics Forums!

In your 3 years of study, it's surprising that none of your subjects dealt with this fantastic idea your group is preparing to demonstrate. Surely someone else must have thought of it before now? It would be so revolutionary if it could be made to work.

Has anyone in your group voiced misgivings about it, or do you anticipate any significant problems?
 
jovel.happy said:
I'm a graduating student of Electrical Engineering Technology (3 years) and so one of our graduating subject is thesis. We decided to make a generator that can supply the house and supply itself by giving some of the power to back to the motor which rotates it. We also included batteries and PLC.

It works like this, first the battery will power the motor, the motor will spin the generator. Some of the power will go back to the motor and the battery. Once the power from the generator goes back to the motor, using PLC, the battery will now stop supplying the motor and recharge, it will only supply back the motor when needed, using PLC. We still haven't made design for the PLC.

Homework Statement
https://scontent-a-lax.xx.fbcdn.net/hphotos-xpa1/v/t1.0-9/p417x417/1475966_881102735242274_5637216028457964277_n.jpg?oh=0fccbedf7441a6b55cb2e80a63b3e702&oe=5516453FThe problem is how much power will be delivered to the load and if this design is actually possible. I have this feeling that all of the power will be consumed by the transformer. To find out how much power will go to the load, I need to know how much current will go to the transformer.

The motor will need around 85 amperes in order to operate. So that means the output current of the transformer should be around 100 amperes since some of the current will go to the battery to charge it.

The ideal transformer formula is power in equals power out.
So the output power of the transformer is (24V x 100A) = 2400W
The input power is (230V x I) = 230I
230I = 2400
I = 10 A

That means the transformer needs an input current of 10A, since it is not an ideal transformer the value is higher than 10A.


The attempt at a solution

My classmates said that we will put super capacitor in around the battery. With the help of super capacitor, the charge rate of the battery will increase and its discharge rate will decrease. But I feel even that won't help. They're just mostly laughing while I'm explaining this problem to them. They keep on saying it will work and that I don't need to worry. I'm thinking of leaving the group and join other groups instead.Another thing is the rate of charge of battery. How do I calculate the number of hours it will take to charge the battery. I've come across the formula h = (Ah of battery/A of charger) where h is the number of hours it will take to charge the battery. Does this mean that I can fully recharge a battery very very fast if it can take a large amount of current?

Welcome to the PF.

What you are describing is a "Perpetual Motion Machine" (PMM) or Over-Unity Device. Each of these is a forbidden topic here at the PF. Please follow the links in the quote below from the PF Forbidden Topics List to learn more about why PMMs cannot work.

PF Forbidden Topics said:
Pseudoscience, such as (but not limited to):
Perpetual motion and "free energy" discussions
http://wiki.4hv.org/index.php/Free_Energy_Debunking
http://en.wikipedia.org/wiki/Perpetual_motion
http://www.skepdic.com/freeenergy.html
http://www.skepdic.com/perpetual.html
 
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