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Which power do i need to run a motor as a generator in the following environment? Answered

I want to generate electricity with a rotating axis at a power of 3 Watt. The mechanical torque (depending on the gearbox) on the input axis varies between 0.73 Nm (@ 250 rpm) and 0.122 Nm (@ 1500 rpm).

Currently i am thinking about a synchronous machine, because it yields higher efficiency, but it is very difficult for me to find a synchronous machine fulfilling the mechanical torque regarding the power. 

Furthermore i usually just find motors in that size, so i need to turn them around but i have problems understanding the data sheet. For example this motor:

Name: ASM 16
Output Power: 3.1 W
Input Power: 9.2 VA
Rotation velocity: 1000 rpm

As this is a motor, but i want to use it as a generator, should i align the output power from the motor with my input power (the 3 W mentioned above, and than as a generator)? 

Can you please give me some ideas how o progress from here? 


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5 years ago

Dear Falko,

It is true that most electric motors can behave as generators on overhauling loads,

Meaning where mechanical energy is supplied to the machine and gets converted to electrical energy.

A flea power 3W synchronous machine unless it is a PM synchronous is rather a poor generator.

Some machines particularly induction machines require excitation in order to become generators ie AC capacitors wired delta across the 3 phases.


Answer 5 years ago

Using a modern speed controlled hand drill and a voltmeter is an easy way to quickly test a motor to see if it can be a generator.... Do this to every motor you come across and build up your knowledge base.