Battery that will run a dc motor

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Discussion Overview

The discussion revolves around the feasibility of using a battery to run a DC motor, which in turn powers a three-phase AC generator. The proposed system includes utilizing two phases of the AC generator for a load while one phase is intended to recharge the battery. Participants explore the theoretical and practical implications of this setup.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant suggests that while it is theoretically possible to recharge the battery using the AC generator, practical limitations such as friction and electrical losses make it impractical.
  • Another participant argues that even with 100% efficiency, the phase used for recharging cannot replenish the battery faster than it is drained by the load on the other two phases.
  • A different viewpoint states that the concept violates the conservation of energy, asserting that a perpetual motion machine cannot be created.
  • Some participants express skepticism about the possibility of eliminating all losses in the system.
  • There are inquiries about research related to perpetual motion machines, but one participant notes that such discussions are not entertained in the forum.

Areas of Agreement / Disagreement

Participants generally disagree on the practicality of the proposed system. While some acknowledge the theoretical possibility, others emphasize the impracticality and violation of energy conservation principles. No consensus exists on the feasibility of achieving a self-sustaining system.

Contextual Notes

The discussion highlights limitations related to energy conversion processes and the inherent irreversibilities that prevent full recharging of the battery. There is an emphasis on the impossibility of creating a perpetual motion machine within the constraints of known physical laws.

Mujahid
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hi i am new to this forum. i want to use a battery that will run a dc motor, dc motor will run three phase ac generator through mechanical coupling and the three phase ac generator will produce out put, now two phases of the ac generator will b utlilized by the load and 1 phase will recharge the battery. my question is wheather its possible or not?
 
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yes is possible. But you will need to separately and independently recharge the battery periodically since friction and electrical losses cannot be overcome.
In other words its impractical.

Try here for practical insights: http://en.wikipedia.org/wiki/Hybrid_car
 


sir you mean its theoratically possible but practically impossible?
 


no I mean it can be done but accomplishes nothing...except temporarily until the battery runs down...trying to recharge the battery from the output consumes more energy than it produces...
 


Even theoretically with 100% efficiency and no losses anywhere in the system the 1 phase used for recharging cannot recharge the battery faster than it is being drained if there is a load on the other 2 phases.

It is certainly possible to build the device you describe, but it won't recharge the battery as fast as it is drained.
 


No, it is not possible. Violates conservation of energy.
 


how sir?
 


is there any alternative?
 


Mujahid said:
hi i am new to this forum. i want to use a battery that will run a dc motor, dc motor will run three phase ac generator through mechanical coupling and the three phase ac generator will produce out put, now two phases of the ac generator will b utlilized by the load and 1 phase will recharge the battery. my question is wheather its possible or not?

If you use part of the converted a/c power to charge the battery there will still be a net loss of energy (due to irreversibilities in the conversion process). So strictly speaking you can "charge" the battery, but you can't fully recharge it such that it violates the conservation of energy.

In other words you cannot create a perpetual motion machine. The battery will eventually drain completely.

CS
 
  • #10


Yes, charge it with an external power source.
 
  • #11


This is the third post of this exact topic by the same user...

Do not multipost...

CS
 
  • #12


can we eliminate all the losses?
 
  • #13


is there any research on practical perpetual motion machine?
 
  • #14


Mujahid said:
is there any research on practical perpetual motion machine?

We do not discuss perpetual motion machines here on the PF because it is a waste of time. Please re-read the Rules link at the top of the page.

Thread closed.
 

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