High power bicycle pedal generator for recharging batteries. Bicycle generator design review Installing a generator on a bicycle

There is a special device that can generate power energy. Such a device is a bicycle generator. The resulting electricity is absolutely free. The production process occurs by scrolling the pedals. According to the types of bicycle generators, there are 4 types:

• Bottle.
• Bushing.
• Contactless.
• Carriage.

The frequency of pedaling is quite closely and almost inextricably linked with the output of current and voltage. This reproduction is typical for all types of generators. The bicycle generator produces only alternating current. To ensure constant current, it is necessary to install a rectifier bridge. It consists of specialized diode lamps. Or you can install a two-half-cycle rectifier. You can buy a generator for a bicycle in special stores, as well as at car markets.

Bottle generator for bicycle

This type of generator is called a bus generator. By type it is a secondary value generator. The bicycle bottle generator consists of a housing that is completely insulated. On the outside there is a special roller that is designed for rotation. It is tightly attached to the body, that is, to the plug. Also, the filling of this generator consists of a conventional copper winding and a magnet. The movement of a magnetic field occurs due to the contact of the roller with the tire of the bicycle wheel. Based on this, energy is transferred from the wheel to the mechanics.

The faster the wheel rotates, the faster the roller on the generator rotates. Maximum polarity is achieved in the generator itself, and voltage is reproduced.

The positive side of this type of generator is:

• Low price relative to other types.
• Easy to install on a bike.
• The device can be easily turned off or on by moving away from the bicycle.

As for the shortcomings, they are not so significant:

• The tire begins to wear out over time.
• It takes time to set the incline level.
• The appearance of sound due to friction against the tire, especially at high speeds.
• Slight misalignment of the wheel due to the weight of the generator, which ranges from 200-250 grams. This is connected due to its fastening on one side.
• If the weather is rainy, the generator does not operate at full capacity. The friction on the wheel is insufficient due to sliding.

But taking into account these disadvantages and advantages, in general, this type of generator is quite effective.

Contactless generator for bicycle

Electricity is supplied through the operation of a bottle generator. The carriage also produces current. In another way, this type of bicycle generator is called a hub dynamo. The name comes from the fact that there is no contact between the generator and the wheel. The current appears as a result of close contact of the rim to the generator. This is what causes the magnetized field of the wheel rim to form.

The lighting diode is directly installed in the device. The voltage goes directly, without any additional stabilization devices. The positive aspects of this device are:

• No friction factors on the wheel.
• Compact and light weight, up to 70 grams.
• There are no connection cables.

The headlight, which is located at the front, is installed on the fork. Taillight - rear. Based on this, these flashlights are independent in themselves. They burn not due to batteries, but due to the rotation of the wheel in a magnetic field. The quality of lighting is at a sufficient level. When riding a bicycle in slow motion, the lights should go out, but this is not the case. This does not happen due to the fact that a special capacitor is installed. In essence, it can be called a battery that gains energy while riding a bicycle.

Conclusion

Using a bicycle generator is beneficial. Firstly, absolutely free electricity generation. Secondly, convenient and comfortable road lighting at night. The 12 volt DC bicycle generator is convenient to use and easy to install. It can also be assembled almost quickly. Does not take up much space during transportation. A bicycle generator does not cause any harm.

When using conventional bicycle dynamics, the question of their durability always arises. After all, in such a device the rotor rotates, as a result of which friction occurs in the bearings (or bushings), which subsequently destroys the generator. Also, the excess friction force leads to a loss of energy, that is, the bicycle does not roll as far and you need to put in more effort to accelerate it.

A way out of this situation may be to use a contactless generator. This device has no rotating parts and can work almost forever. As a rule, the role of the rotor is played by the bicycle wheel itself, and the stator is attached to the frame or fork. The cost of such generators is quite high, so it makes sense to try to create one yourself.

Below we will consider the simplest way to create a contactless generator for a bicycle. But this is just a model, a principle that can be used to create similar homemade products.

Materials and tools for homemade work:
- a powerful magnet (the author uses neodymium from a hard drive);
- three coils (you can make it yourself);
- rear light with three LEDs;
- 4700 nF capacitor;
- headlight (with five white LEDs);
- double switch from the computer power supply;
- two screws with nuts and washers (for attaching the magnet to the wheel);
- screwdrivers and wrenches, soldering iron, electrical tape;
- wires, switches and other small items.

Step one. Installing generator elements on a bicycle
Everything works according to a very simple scheme. A powerful neodymium magnet from a computer hard drive is attached to the bicycle wheel using two screws and nuts (The author uses three magnets, this eliminates vibrations. You can use more). A coil is placed opposite it to the bicycle fork at a minimum distance; when a magnet passes near it, a current arises in it. The author has three coils, one is needed to operate the rear light, and two are needed to operate the front light. Since the current is pulsed, the lights will flash while driving. The closer the magnet passes near the coil, the more energy it can generate.

How to generate electricity by pedaling? One kilowatt-hour costs 5 cents. To obtain this amount of energy, you need to pedal for 10 hours. There is no point in talking about industrial scale electricity production using pedal generators. Nevertheless, this method of generating electric current is required quite often, because with the help of muscular power we can generate electricity anywhere without consuming fuel, day or night. The equipment is cheap and requires virtually no maintenance.

They are mainly required in two cases:

1. For when traveling by bike.
2. To generate as much electricity as possible using stationary pedal generators.

Pedal bicycle generators are designed to generate electricity in remote areas where it is inconvenient to use solar panels. A generator for a bicycle can generate up to 300 W of electricity (on average 40-150 W depending on the cyclist).

There are many recommendations on the Internet that work by rotating the pedals. not the best choice as they contain many rare unnecessary parts or require a lot of work to adapt the alternator to the bike, suffer from friction problems, belt slippage and rapid wear.

How to choose the right bike generator.

• The motor is installed on a stationary bicycle - it is a rear hub motor (the front wheel of a stationary bicycle does not rotate).
• For good performance, the motor must use modern rare-earth permanent magnets, and the bicycle generator must be of a brushless design.
• To get a good inertia effect, it must be heavy and be an electric bicycle wheel.
• To reduce mechanical losses, the motor should be direct drive/not use gears.
• In order for a person to cope with pedaling for a long time, the motor must produce a power of at least 200 W. The more, the better (losses decrease, weight increases).
• The motor voltage must exceed the specified output voltage so that it does not fall below a critical value, even when pedaling at less than full power.

The figure above shows the internal structure of the wheel motor, designed as a 24V, 500W hub generator manufactured by Golden Motor / Jiangsu, charging a 12V battery.

Installing a generator on a bicycle.

1. Find a bicycle - any junk, but with a working front axle, pedals, chain, saddle and preferably a rear derailleur.
2. Replace the rear wheel with a hub motor.
3. Place the bike on a stand so that the rear wheel can rotate freely. You can also hang the back of the bicycle so that it does not touch the ground at all; take a stand made of metal brackets mounted on a wooden base.

You can return the bike to its original state very quickly - you just need to remove it from the support and put the wheel back.

Electrical circuit for recharging batteries using a pedal generator.

The motor-generator is located on the left of the circuit, the output voltage (+/-12 V) is on the right. You can connect any load to the output: light bulbs, fluorescent lamps, LED lighting equipment, radio, TV, satellite receiver, inverter. All connected devices must be rated for 12 V.

Let's look at the diagram in more detail. The bicycle generator produces 3-phase alternating current, which must be converted to direct current before use. A three-phase rectifier can be made from six diodes or purchased ready-made (used in wind energy). It looks like a regular bridge rectifier, only it has five terminals instead of four. The rectifier must be rated at least 100 V and 35 A. Each of the diodes must withstand the same voltage, but only half the current (20 A). The straightener requires some cooling - so attach it to a large metal piece.

The output power of the rectifier cannot be directly supplied to a light bulb or TV, since it does not produce a stable voltage. It will fluctuate between zero and maximum and may damage the equipment. This problem is solved by connecting the battery in parallel to the output of the rectifier, which will absorb the excess power generated by the generator and fill the periods of time when the generator does not produce enough power or even stops for a short time. The battery does not have to be large or anything special - any lead-acid battery will do. If it has a large capacity, that's also good. You can use an old 12V 16Ah computer UPS battery. For home use, sealed batteries that do not emit gases are recommended.

There are other components in the diagram. One of them is a fuse, which is needed in case of a short circuit. The battery produces so much current that it can even ignite the cable. A 2.5 mm 2 cable and a 30 A fuse are recommended. There are also two measuring instruments on the diagram (not in the photo). One voltmeter (with its own fuse) and one ammeter. Despite the fact that the pedal generator works without them, a voltmeter is highly recommended for the sake of battery health. It's better to take a digital voltmeter. As soon as it displays 14 V (for 12 V systems), you need to stop rotating. Never exceed 15 V. The voltage should also not fall below 10.5 V. The analog ammeter (with a zero mark in the middle of the scale) is not very important, but it shows whether energy is being pumped into the battery (eventually leading to a full charge of the battery) or consumption ( leading to battery discharge). The circuit cannot use a digital ammeter because the current changes too frequently to provide a consistent reading. The range of the ammeter depends on the current drawn by the load. It is best to buy one with a range of +/- 20 A.

The relationship between battery voltage, generator voltage, front and rear sprocket sizes.

The voltage of the battery and generator, the size of the front and rear sprockets affect the effort expended by a person and his cadence. With the correct selection of these parameters at the selected power, the system produces the required output voltage at an adequate cadence (50 - 60 rpm).

To check this dependence in practice, you need to set the generator voltage higher than the battery voltage, and also try using different gears (you will need a bicycle with a working shifter).

As the battery charges, the cadence increases and only timely changing of the sprockets with the switch allows you to maintain a stable cadence. The presence of gears is also necessary for individual adjustment of the pedal generator for each individual person.

Technical specifications of the Golden Motor/Jiangsu based system: 24V alternator, 12V battery, 42T chainring, 14T rear sprocket (18T if battery voltage is below 11V).

Although there are records. During one of the tests, it was possible to generate 12 kWh in 24 hours. But this is not the limit; Siemens stated that it had created an installation with the help of which a person was able to obtain 4.2 kW/h in an hour. But 62-year-old inventor Manoj Bhargava assembled a unique exercise bike. Using it for just one hour can provide electricity to a small house for a whole day. The scientist hopes that Free Electric (as he called his invention) will help solve problems with electricity supply in third world countries. Let's watch a video about it:

Now look at the photo below. What do you think these people are doing?

These are prisoners, violators of the order of the colony, in one of the Brazilian prisons, instead of a punishment cell, they generate electricity. They charge batteries that are used to power Santa Rita's lights at night. And the idea was taken by the head of this institution in the women's prison in Phoenix (Arizona, USA). There, convicts pedal for 16 hours a day, and this counts towards their 24-hour sentence. This way they shorten their time.

Application of electric generator

Where can a bicycle electric generator be used in our everyday life?
You can, for example, charge your phone while exercising in the morning. Well, really, why not exercise and save energy at the same time? Measure how long it takes to charge your cell phone. Try to remember the time and try to beat it in the future.
You can combine business with pleasure, so to speak - see if you can generate as much energy as the blender consumes. Then you can make yourself a sports cocktail.

If you have a technically adventurous child, why not try bringing this idea to life just for the experience.
Use your imagination and maybe some other funny ideas will come to your mind.

It is possible that you will want to bring your ideas to life. What do you need for this?

• Bike. An old one that has not been used for a long time or has been lying around is perfect for these purposes.
• 12V DC motor.
• V-belt for connecting the rear wheel to the engine.
• Beam for stand 100*50 mm.
• Diode.
• Battery 12V.
• An inverter that converts direct current 12V into alternating current 220V.

If you do not plan to connect anything other than a DC light bulb to this device, then you can do without the last three points.
And they will be needed to connect other electrical appliances. The reason for this is the uneven voltage that will come from the generator (electric motor).

How to make an electric generator

Let's get started. I am posting two diagrams for comparison. On the first, the pedal generator can only power DC light bulbs, and on the second, it can fully work with devices designed for 220V AC. We choose a scheme.