Electric motor + flywheel

[dvx]

Here is a couple of questions:

If a flywheel is attached to a 3/4 HP electrical motor will this increase the output of this set (motor+flywheel)?

If there is an increase than what is the maximum output that can be created in the case of a motor + flywheel using a 3/4 HP electric motor?

Regards,

 

[electricpete]

Flywheel will not increase the steady state thermal limit of the motor.

Flywheel can increase the momentary overload torque which can sustained without going beyond breakdown torque. In some cases, this means you can comfortably power a larger load with the same motor.

When flywheel is added, effect on motor starting needs to be looked at.

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(2B)+(2B)' ?

 

[electricpete]

I should clarify, 3/4 hp would generally be max steady state load regardless of flywheel (unless you plan to accept overload in service factor) based on steady state thermal limit. If you have a load which gives high torque spikes, then you may need to limit torque below 3/4 hp limit. Flywheel may help you get back to 3 / 4hp.

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(2B)+(2B)' ?

 

[desertfox]

Hi dvx

The flywheel will store energy from the motor as it rotates the purpose of the flywheel is to smooth out fluctuations in torque loadings.

 

[jraef]

Nullum Gratuitum Prandium (There is no free lunch ).

In other words, energy in = energy out. The flywheel adds no energy to the equation. It can store energy and release it later, but all of the energy it contains will have come from that 3/4 HP motor.

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
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[waross]

If you are thinking about driving a fluctuating load with a flywheel you may want to search the Baldor site for the Cowern Papers. Look at RMS loading. Generally when a flywheel is used the motor is a high slip motor. With a low slip motor you don't get much energy from the flywheel before the motor is badly overloaded.
The high slip motors with flywheels are used on loads with short, high torque demands such as shears, punches and alligator shears.

Bill
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"Why not the best?"
Jimmy Carter

 

[KiwiMace]

Due to mechanical losses associated with the flywheel, the power from your 3/4hp motor will be slightly reduced in steady state.

Another application is to limit the rate of change - I have used flywheels on pump motors to reduce surge in the pipeline caused by starting and stopping pressure transients. (Soft start does not protect from power failure).