Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [dynamo]

26 questions
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Building a solid state generator/dynamo voltage regulator, to replace an old mechanical regulator

I like to restore vintage motorcycles, which commonly use 6V electrics. The vintage bikes use a 6V dynamo or generator to produce DC which is then regulated to a constant 6V. The current method in a vehicle, or on a motorbike, uses AC produced by an…
David Maher
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Can an inverter through a battery charger charge its own batteries?

I understand some of these laws of thermodynamics. An alternative to this question, being inventive, is 'Can an inverter power a dynamo (which is powered by an electric motor) to charge the same inverter batteries?' It may seem redundant but I am…
Jeswills
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Charging an 18650 Li-Ion cell via a bicycle hub dynamo

I'm interested in building a buffer battery for a 12V GPS tracker using a single 18650 Li-Ion cell. It will be mounted on a bicycle and unfortunately I haven't found a design for a tracker including battery that works exactly how I want. The general…
J. Komets
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Building a solid state regulator for a vintage 6 V dynamo

There was a great discussion back a few months ago on building a regulator for a dynamo. I have a similar challenge except the vintage motorcycle I'm restoring is a racing machine - neither lights not a battery (and no place for them). To the best…
clairefromperth
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3 answers

AC overvoltage protection for bike dynamo (alternator)

I built my own MOSFET active rectifier and DC/DC stepdown for a bike dynamo hub and wanted to use it for charging a mobile phone. The circuit is working, but there is one thing which needs to be solved better. When USB output (5V) is not connected…
mavit
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Dynamo - Reversing the rotation of the shaft

I'm having a debate with a friend. He claims that if you change the rotation of the shaft of a dynamo the output DC current changes direction. I, however, claim otherwise. The way I see it is that a dynamo rotates a coil inside a magnetic field,…
rr1303
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AC to DC 6 V for bicycle and super capacitors for lights

I’m trying to design a circuit to enable my bicycle lights and also have at least 2 minutes of standing lights coming from a bicycle 6 V AC hub. I thought about building a rectifier bridge with 4 1N5820 diodes and then have 3 sets of capacitors: 1…
Joe
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what force is required to rotate a dynamo or alternator

I am working on an initiative for a new product. The product generates a rotational output force from: Input force of 14.73 NM Input speed 120 rpm Gear ratios from 0.5 - 2 The out rotation is intended to produce electricity so therefore it will…
Robert
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Alternator without permanent magnets and without external power source

From the answers to the following question (1), I gather that it is theoretically possible to operate an alternator / dynamo / generator: Without permanent magnets. With an external energy source for the electromagnet which substitute themselves…
Serge Hulne
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In a Shimano dynamo hub with 6V regulator is the rest of the power being wasted?

I bought a Shimano hub dynamo that gives a maximum of 6 V with a regulator that they have provided. From what others here have said, the regulator is a Zener diode. The output voltage of the dynamo increases with speed at which the bicycle is…
MikePainter
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Is this circuit correct?

I need to know if this circuit is efficient to transfer most of the current from several identical independent 2 phase dynamos. The converters are all the same and ideal for the voltages no problem with that. Is this the correct way? Thanks!
Soko Fuzu
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Step up dynamo voltage with transformer

I'm using a 100 turn coil and some magnets to create a 100 mV AC signal from my bike wheel. I need to boost that voltage up to at least 400 mV to use a DC-DC boost converter to get 5 V. For that reason, I'm trying to use a 1:5 transformer to boost…
Nasib Fahim
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Bike power supply system

My idea is to build a electronic system for my bike to supply my phone and lights with energy. I want to use a Dynamo (6 V, 3 W) to charge a USB Powerbank. From its two USB ports I want to charge my phone and run the front and back light. As a front…
TJLW
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Different fan size in same duct

Im trying to build pc cabinet such that there is 3 fan input to cabinet, and just one output which is the smps inbuilt fan. Then seal off all other air gaps. Q. Will the smps fan break due to receiving 3x its capability? Or reprase as, Will using…
iuofk
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Regulating the output of a vintage motorcycle dynamo

I am restoring a late 1940s Velocette Mac 350 motorbike. I have a few working dynamos for this bike, but the original regulators are hard to find in working condition. I bought a regulator on Aliexpress, but I am pretty sure now that this regulator…
David Maher
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