Generator from a motor from a hard drive. How to assemble a wind generator from three hard drives and one pump from a washing machine

Riding a bicycle past summer cottages, I saw a working wind generator:

Large blades rotated slowly but surely, the weather vane oriented the device in the direction of the wind.
I wanted to implement a similar design, albeit not capable of generating enough power to provide "serious" consumers, but still working and, for example, charging batteries or powering LEDs.

Stepper motors

One of the most effective options for a small homemade wind turbine is to use stepper motor(SHD) (English) stepping (stepper, step) motor) - in such a motor, the rotation of the shaft consists of small steps. The windings of a stepper motor are combined into phases. When current is applied to one of the phases, the shaft moves one step.
These engines are low-speed and a generator with such an engine can be connected without a gearbox to a wind turbine, Stirling engine or other low-speed power source. When using a conventional (collector) DC motor as a generator, a 10-15 times higher speed would be required to achieve the same results.
A feature of the stepper is a fairly high starting torque (even without an electrical load connected to the generator), reaching 40 grams of force per centimeter.
The efficiency of the generator with stepper motor reaches 40%.

To check the performance of a stepper motor, you can connect, for example, a red LED. By rotating the motor shaft, you can observe the glow of the LED. The polarity of the LED connection does not matter, as the motor generates alternating current.

Five-inch floppy disk drives, as well as old printers and scanners, are a storehouse of such powerful enough engines.

Engine 1

For example, I have a SD from an old 5.25″ drive that was still working as part of ZX Spectrum- compatible computer "Byte".
Such a drive contains two windings, from the ends and the middle of which conclusions are drawn - in total, six wires:

first winding coil 1) - blue (English) blue) and yellow (eng. yellow);
second winding coil 2) - red (eng. red) and white (eng. white);
brown (English) brown) wires - conclusions from the midpoints of each winding (eng. center taps).

disassembled stepper motor

On the left, the rotor of the engine is visible, on which "striped" magnetic poles are visible - north and south. To the right is the stator winding, consisting of eight coils.
The resistance of half of the winding is ~ 70 ohms.

I used this motor in my original wind turbine design.

Engine 2

My less powerful stepper motor T1319635 firms Epoch Electronics Corp. from the scanner HP Scanjet 2400 It has five outputs (unipolar motor):

first winding coil 1) - orange (English) orange) and black (eng. black);
second winding coil 2) - brown (eng. brown) and yellow (eng. yellow);
red (English) red) wire - leads connected together from the midpoint of each winding (eng. center taps).

The resistance of half of the winding is 58 ohms, which is indicated on the motor housing.

Engine 3

In an improved version of the wind generator, I used a stepper motor Robotron SPA 42/100-558, produced in the GDR and designed for a voltage of 12 V:

wind turbine

There are two options for the location of the axis of the impeller (turbine) of the wind generator - horizontal and vertical.

advantage horizontal(most popular) location axis, located in the direction of the wind, is a more efficient use of wind energy, the disadvantage is the complexity of the design.

I chose vertical arrangement axes - VAWT (vertical axis wind turbine), which greatly simplifies the design and does not require orientation to the wind . This option is more suitable for roof mounting, it is much more effective in conditions of rapid and frequent changes in wind direction.

I used a type of wind turbine called a Savonius wind turbine. Savonius wind turbine). It was invented in 1922 Sigurd Johannes Savonius) from Finland.

Sigurd Johannes Savonius

The operation of the Savonius wind turbine is based on the fact that the resistance (Eng. drag) to the oncoming air flow - the wind of the concave surface of the cylinder (blade) is greater than the convex one.

Aerodynamic drag coefficients ( English drag coefficients) $C_D$

two-dimensional bodies:
concave half cylinder (1) - 2.30
convex half of the cylinder (2) - 1.20
flat square plate - 1.17
3D bodies:
concave hollow hemisphere (3) - 1.42
convex hollow hemisphere (4) - 0.38
sphere - 0.5
The indicated values are given for Reynolds numbers (eng. Reynolds numbers) in the range $10^4 - 10^6$. The Reynolds number characterizes the behavior of a body in a medium.

Body resistance to air flow $(F_D) = ((1 \over 2) (C_D) S \rho (v^2) ) $, where $\rho$ is air density, $v$ is air flow velocity, $S $ - sectional area of the body.

Such a wind turbine rotates in the same direction, regardless of the direction of the wind:

A similar principle of operation is used in a cup anemometer (eng. cup anemometer)- instrument for measuring wind speed:

Such an anemometer was invented in 1846 by the Irish astronomer John Thomas Romney Robinson ( John Thomas Romney Robinson):

Robinson believed that the cups in his four-cup anemometer moved at a speed equal to one third of the wind speed. In reality, this value ranges from two to a little more than three.

Currently, three-cup anemometers, developed by Canadian meteorologist John Patterson, are used to measure wind speed ( John Patterson) in 1926:

DC brushed motor generators with a vertical microturbine are sold at eBay for about $5:

Such a turbine contains four blades located along two perpendicular axes, with an impeller diameter of 100 mm, a blade height of 60 mm, a chord length of 30 mm, and a segment height of 11 mm. The impeller is mounted on the shaft of the DC commutator micromotor with the marking JQ24-125H670. The rated supply voltage of such a motor is 3 ... 12 V.
The energy generated by such a generator is enough to light up the "white" LED.

Savonius wind turbine rotation speed cannot exceed wind speed , but this design is characterized high torque (English) torque).

The efficiency of a wind turbine can be estimated by comparing the power generated by the wind generator with the power contained in the wind blowing around the turbine:
$P = (1\over 2) \rho S (v^3)$ , where $\rho$ is the air density (about 1.225 kg/m 3 at sea level), $S$ is the swept area of the turbine (eng. swept area), $v$ - wind speed.

My wind turbine

Option 1

Initially, the impeller of my generator used four blades in the form of segments (halves) of cylinders cut from plastic pipes:

Segment sizes -
segment length - 14 cm;
segment height - 2 cm;
segment chord length - 4 cm;

I installed the assembled structure on a fairly high (6 m 70 cm) wooden mast from a bar, attached with self-tapping screws to a metal frame:

Option 2

The disadvantage of the generator was the rather high wind speed required to spin the blades. To increase the surface area, I used blades cut from plastic bottles:

Segment sizes -
segment length - 18 cm;
segment height - 5 cm;
segment chord length - 7 cm;
the distance from the beginning of the segment to the center of the axis of rotation is 3 cm.

Option 3

The problem turned out to be the strength of the blade holders. At first I used perforated aluminum strips from a Soviet children's designer 1 mm thick. After several days of operation, strong gusts of wind led to a break in the slats (1). After this failure, I decided to cut out the blade holders from foil textolite (2) with a thickness of 1.8 mm:

The bending strength of the textolite perpendicular to the plate is 204 MPa and is comparable to the bending strength of aluminum - 275 MPa. But the modulus of elasticity of aluminum $E$ (70000 MPa) is much higher than that of textolite (10000 MPa), i.e. Texolite is much more elastic than aluminium. This, in my opinion, taking into account the greater thickness of the textolite holders, will provide much greater reliability of fastening the wind turbine blades.
The wind generator is mounted on a mast:

Trial operation of a new version of the wind generator showed its reliability even with strong gusts of wind.

The disadvantage of the Savonius turbine is low efficiency - only about 15% of the wind energy is converted into shaft rotational energy (this is much less than can be achieved with wind turbine Darya(English) Darrieus wind turbine)), using lifting force (eng. lift). This type of wind turbine was invented by the French aircraft designer Georges Darier. (Georges Jean Marie Darrieus) - 1931 U.S. Patent #1,835,018 .

Georges Darier

The disadvantage of the Darrieus turbine is that it has very poor self-starting (the turbine must already be spinning up to generate torque from the wind).

Converting the electricity generated by the stepper motor

The stepper motor leads can be connected to two Schottky bridge rectifiers to reduce the voltage drop across the diodes.
You can use popular Schottky diodes 1N5817 with a maximum reverse voltage of 20 V, 1N5819- 40 V and a maximum direct average rectified current of 1 A. I connected the outputs of the rectifiers in series in order to increase the output voltage.
You can also use two mid-point rectifiers. Such a rectifier requires half as many diodes, but at the same time, the output voltage is also reduced by half.
Then the ripple voltage is smoothed out using a capacitive filter - a 1000 uF capacitor at 25 V. To protect against increased generated voltage, a 25 V zener diode is connected in parallel with the capacitor.

my wind turbine diagram

electronic unit of my wind generator

Wind turbine application

The voltage generated by the wind generator depends on the magnitude and constancy of the wind speed.

With the wind swaying the thin branches of trees, the voltage reaches 2 ... 3 V.

With the wind swaying the thick branches of trees, the voltage reaches 4 ... 5 V (with strong gusts - up to 7 V).

CONNECTING TO JOULE THIEF

The smoothed voltage from the wind generator capacitor can be fed to - low-voltage DC-DC converter

Resistor resistance value R is selected experimentally (depending on the type of transistor) - it is advisable to use a 4.7 kΩ variable resistor and gradually reduce its resistance, achieving stable operation of the converter.
I assembled such a converter based on germanium pnp- transistor GT308V ( VT) and pulse transformer MIT-4V (coil L1- conclusions 2-3, L2- conclusions 5-6):

CHARGE OF IONISTORS (SUPERCAPACITORS)

Ionistor (supercapacitor, eng. supercapacitor) is a hybrid of a capacitor and a chemical current source.
Ionistor - non-polar element, but one of the terminals may be marked with an "arrow" - to indicate the polarity of the residual voltage after it has been charged at the factory.
For initial research, I used an ionistor with a capacity of 0.22 F for a voltage of 5.5 V (diameter 11.5 mm, height 3.5 mm):

I connected it through a diode to the output through a germanium diode D310.

To limit the maximum charging voltage of the ionistor, you can use a zener diode or a chain of LEDs - I use a chain of two red LEDs:

To prevent the discharge of an already charged ionistor through the limit LEDs HL1 And HL2 I added another diode - VD2.

To be continued

You will definitely like this material, as in it we will look at how to get a simple generator from an old computer CD / DVD drive.

First of all, we offer you to get acquainted with the author's video

Consider what we need:
- old CD/DVD drive;
- wire cutters;
- soldering iron;
- any plastic case;
- wires;
- hexagon;
- washer.

According to the author of the homemade generator, the idea is quite effective, since the ratio of the gear ratio to the motor that drives the gear that pushes the disc tray is quite large. Thus, it is possible that at low revolutions of the same gear, good revolutions will be obtained on the electric motor, and we will be able to get a generator. Whether the plan will turn out or not, we will find out at the end of the review, and now let's get to work.

First you need to unsolder the board on which the motor is mounted.

Next, we cut off the part of the plastic drive housing on which the motor rests, as well as the gear we need. Later, we will remove the handle from this gear so that we can turn it and generate electricity.

We take the first wire and solder it to one of the contacts of the motor.

Solder the second wire to the second contact.

To test the generator, the author of the idea uses UBS inputs, which are installed in a plastic case. So he glues a piece of drive with a motor and gear into this case using a glue gun.

To make a handle, you will need a hexagon and a washer. These parts need to be attached to each other. The author does this by soldering.

Solder the wires to the USB connectors.

On the second half of the plastic case, you need to make a hole for the gear ledge.

Finally, glue the homemade handle to the ledge of the gear. Our generator is ready.

In this article, we will consider a model of a powerful magnet generator that is capable of generating electricity with a power of 300 watts. The frame is assembled from dural plates 10 mm thick. The generator consists of 3 main parts: housing, rotor, stator. The main purpose of the housing is to fix the rotor and stator in a strictly defined position. The rotating rotor must not touch the stator coils with magnets. The duralumin case is assembled from 4 parts. The angular layout provides a simple and rigid structure. The body is made on a CNC machine. This is both a plus and a disadvantage of the development, since for a high-quality repetition of the model, you need to find specialists and a CNC machine. The diameter of the discs is 100 mm.

You can also take a ready-made electric generator in the online store.

The rotor of the electric generator I. Belitsky

Rotor is an iron axle. On it are fixed 2 iron disks with neodymium magnets located on them. An iron bushing is pressed between the discs on the axle. Its length depends on the thickness of the stator. Its purpose is to provide a minimum gap between the rotating magnets and the stator coils. Each disk contains 12 neodymium magnets with a diameter of 15 mm and a thickness of 5 mm. For them seats are made on a disk.

They need to be glued with epoxy or other glue. In this case, it is necessary to strictly observe the polarity. In the assembled state, the magnets should be located so that opposite each is another from the opposite disk. In this case, the poles must be different towards each other. As the author of the development himself writes (Igor Beletsky): “It will be right to have different poles, so that the lines of force come out of one and enter the other, definitely S = N.” You can buy neodymium magnets in a Chinese online store.

Stator device

Sheet textolite 12 m thick was used as a base. Holes for coils and rotor bushings were made in the sheet. The outer diameter of the iron coils that are installed in these holes is 25 mm. The inner diameter is equal to the diameter of the magnets (15 mm). Coils perform 2 tasks: the function of a magnetically conductive core and the task of reducing sticking when moving from one coil to another.

Coils are made of insulated wire 0.5 mm thick. 130 turns are wound on each coil. The direction of winding is the same for all.

When creating a powerful generator from, you need to know that the higher the speed that can be provided, the higher the output voltage and current of the device will be for free energy.

We continue to recycle plastic bottles. I propose to consider the manufacture of a vertical rotary windmill from four bottles. The rotation assembly used can become a generator of weak currents or an excellent wind speed sensor for a homemade anemometer. Showing photos and videos of a windmill. The assembly diagram is detailed below.

How to make a windmill from PET bottles with your own hands

1. Necessary tools: heat gun, scissors, drill, knife and screwdriver. Materials used: four identical PET bottles with caps from 0.2 to 2 liters each, a hard drive motor, a plastic vitamin jar, an old sink siphon and a wooden pole of the required length.

2. Disassembly of a computer hard drive is considered. To work, you will need an engine and a patch plate for fixing the disc pancake with fasteners. Fasteners can be under a Phillips screwdriver, but more often under an asterisk.

3. We begin the work with the most time-consuming and responsible unit - installing a rotation unit in the lid of a vitamin jar. To do this, under the end of the engine, a hole in the plastic lid of the jar is cut out with a knife with a knife in a strictly symmetrical way.

Motor Jar Lid Hole

4. We outline the mounting holes on the patch plate and drill them.

5. Install the rotation assembly in the cover.

Holes are marked Rotation knot fixed

6. We mark the jar into four sectors and glue four lids symmetrically with a well-heated thermal gun. Glue is liberally applied to the lid and the lid is glued in the right place. There should be no labels on the jar, and it is advisable to clean the places of gluing with an emery cloth.

7. We screw PET bottles into corks and use a permanent felt-tip pen to mark cutouts in the jar. The position of the cutouts determines the direction of rotation of the windmill. The cutouts should be on the other side as shown in the photo, that is, when rotating, the windmill tries to tighten the cover.

8. Cut out the bottles in turn and immediately screw them into place. We screw the jar into the lid - the homemade windmill is ready. It is useful to check and, if necessary, balance the wheel with a piece of plasticine.

Lids are glued

9. The issue of installing a windmill initially caused difficulty, but was surprisingly simply resolved. The inch standards of the hard drive and the siphon from the sink turned out to be the same, and the engine was remarkably fixed with a union nut on the siphon, if necessary, you can add a rubber washer. Before installation, the engine was disconnected from the cover, the union nut was inserted and the can cover was fixed back. Wires are soldered to the motor windings to evaluate the generating capabilities of the motor.

10. The end of the pole is firmly inserted into the siphon and the whole structure is installed for testing. The windmill is quite sensitive and with a quiet wind immediately began to slowly rotate.

Rotation knot fixed

A simple wind generator can be made from a few faulty hard drives and a water pump from a washing machine. Alternative energy is closer than it seems, now there is more than enough junk to make such necessary gizmos. Such a design, of course, will not power your entire house with electricity, but it will do just fine for charging all kinds of USB gadgets.

It will take

Pump from an automatic washing machine. It stands at the very bottom and serves to pump water from the drum into the sewer.
Four hard drives, can be from different manufacturers.
A pole is a long pipe for mounting a windmill to a height.
Bolts, nuts, washers.
Wires.

A few words about the water pump

A water pump will be used as a generator that generates electricity. It consists of a movable rotor with permanent magnets and a movable stator with a U-shaped magnetic circuit and a coil on it.

The rotor is pretty easy to pull out.

Thanks to the use of permanent magnets, such a pump works perfectly as a generator capable of delivering up to 250 V. Of course, our windmill will not give such speed and the output voltage will be several times less.

Wind turbine manufacturing

It was decided to fix the pump with construction steel corners, bending and cutting them as needed.

It turned out like this, a kind of collar.

A hole was made in the magnetic circuit of the pump for a more secure fixation.

Assembly assembly.

Wind turbine blades

The blades are made from PVC pipe.

We cut the pipe into three even parts along.

And then we cut out our own blade from each half.

We make holes in the places where the blades are attached to the generator.

Blade attachment

For fastening the blades of the wind generator, two disks from the HDD were used.

The hole in which is perfectly suited to the diameter of the impeller.

We mark up.

Drilling.

The discs are attached to the rotor with bolts, washers and nuts.

Screw on the blades.

Swivel

In order for the windmill to rotate in different directions depending on the wind, it must be installed on a turntable, in the role of which the engine from the hard disk will be used, since there are very good bearings.