We are trying to find the total output power that can be taken from a pull chord

Question

We are trying to find the total output power that can be taken from a pull chord. The Pull chord will be geared to maximize power output from a motor with some given specifications. Essentially the motor is being spun by the chord after being geared in order to create power to charge an iphone. The chord will be pulled internally from within the case. Will there be any load on the battery when being charged? If so how will it affect the charging process? How much Force is needed to get the motor running at optimal conditions?

Values at nominal voltage

Supply voltage 24 V No load speed 4530 rpm No load current 36.6 mA Nominal speed 2760 rpm Nominal torque (max. continuous torque) 25.5 mNm Nominal current (max. continuous current) 0.499 A Stall torque 85.8 mNm Starting current 1.75 A Max. efficiency 74 %

Characteristics

Terminal resistance 13.7 ? Terminal inductance 7.73 mH Torque constant 49 mNm/A Speed constant 195 rpm/V Speed / torque gradient 54.5 rpm/mNm Mechanical time constant 20 ms Rotor inertia 35 gcm

Explanation / Answer

r = internal resistance = 24/36.6 = 655 ohm

angular velocity =2760*2*pi/60 rad/s

power = torque*veloangular velocity = 7.366 w

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