Introduction: ELECTRICAL GENERATOR WITH MAGNETIC COUPLING
"The world is changed. I feel it in the water. I feel it in the earth. I smell it in the air. Much that once was is lost..." - The Lord of the Rings.
Certainly ... speaking of Oil and Non-Renewable Energies, much of what it was has been lost. We need new forms of energy production ... Clean and easy to obtain ... without damage to the environment around us. Then I will show you a different way of producing energy ... it is the result of what many have been doing in isolation ... I am simply taking the best ideas and putting them together so that we can get the result wanted. The information shown here is in the public domain. It is based on ideas from the beginning of the last century. But it is until today, that with the emergence of neodymium magnets we can realize the ideas of the past. I use the principle of "Divide and Win." Why have a large, heavy and expensive generator? ... if I can achieve it with several small ones .... The idea is to connect several brushless motors used as a generator and linked to each other through a magnetic gear, in this way we can move several generators with the use of a single motor, thereby increasing the efficiency of the system.
MEXICO, February 9, 202
Step 1: MATERIALS
The materials that we are going to need are:
- CD / DVD drive motors (5 pieces)
- Neodymium magnets 5mm in diameter x 4mm in height. (60 pieces)
- ProtoBoard Double
- Bridge Rectifier 50 V / 1.5 amp. (15 pieces)
- 5mm Red LEDs (5 pieces)
- 5mm Green LEDs (5 pieces)
- 5mm Yellow LEDs (5 pieces)
- Resistors of 150 ohms to 1/4 of watt (15 pieces)
The lego pieces can be found at: www.bricklink.com
- Brick 1x16 (LEGO No. 3703) - (10 Pieces)
- Liftarm 1x11.5 (LEGo No. 32009) - (10 Pieces)
- Liftarm 2x4 L (LEGO No. 32140) - (15 Pieces)
- Axle 3 with Stud (LEGO No. 6587) - (20 Pieces)
- Pin Long with Friction (LEGO No. 6558) - (25 Pieces)
- Glue (Cyanoacrylate)
- 1/16 "(50 cm) heat shrinkable cable
- Orange and Green Phosphorescent Paint
Step 2: MAGNETS ASSEMBLY
BRUSHLESS CD/DVD MOTOR
The motors used in the CD / DVD readers are brushless motors that are formed by a series of windings that deliver an alternating current voltage signal in three phases.
For more information on Brushless motors see the following link:
1.- We will start with the assembly of the engine in its base: For this, we will form a base with the LEGO pieces as shown in the figure and we will fix it to the engine by means of cyanoacrylate glue (KOLA LOKA).
WATCH OUT! The cyanoacrylate glue sticks the skin.
2.- Now we will place the neodymium magnets around the motor. We will place the neodymium magnets with their poles located alternately N-S-N-S-N-S ...
CAUTION! Neodymium magnets are extremely powerful, brittle and can break if they collide with each other. The magnets we are using are really powerful, it has an attractive force of just over 800 grams. However, due to the high speeds that are handled, it is necessary to glue them with cyanoacrylate to the base of the engine. (During the tests, neodymium magnets were dismissed throughout the room in a couple of occasions ... :)
3.- In the end, we paint each magnet of green and red fluorescent colors for better appreciation of its operation.
Step 3: MOTOR WIRING
It is time to assemble the motor cables.
Normally these motors have a thirteen pin connector and the last three (11, 12 and 13) correspond to phases B, C, A.
If this is not the case We have to identify which of the connector pins are the ones that carry the signals to the motor windings.
We can achieve this with the help of a magnifying glass and follow the clues on the printed circuit to the connector.
Step 4: CONSTRUCTION OF THE MOTOR BASE
It is time to build the bases of the engines.
In my case, I used LEGO pieces, as they allow me to quickly capture an idea. We can get the LEGO pieces we need at www.bricklink.com.
Step 5: ELECTRICAL CIRCUIT MOUNT
We are going to build the electrical circuit.
When we use Brushless motors as generators, they give us a three-phase alternating current signal, which we have to rectify to obtain direct current.
We achieve this using rectifier diodes.
In my case, I used a complete rectifier bridge for each phase of the motor.
Half of a bridge rectifier can be used, but I prefer to use it twice and thus increase the current that I can handle for each rectifier.
The circuit used in this project is only to demonstrate the voltage that is generated in each phase.
In a practical application, the rectifier outputs of each phase are connected together.
Step 6: JOINING THE PARTS
It is time to put everything together.
The motors are placed next to each other and the separation between them is adjusted. The closer they are, the faster we can get without losing synchronism between them when they are spinning at high speeds. The cables of each motor are connected to their corresponding rectifier bridges.
IMPORTANT: You have to fix the pieces to a base so that everything stays firm. We will drive high speeds and we will have many vibrations.
Step 7: TESTS AND RESULTS
RESULTS OF THIS FIRST STAGE (I):
Several tests were performed and the following results were obtained:
- The faster the motor rotates, the more voltage we get (Faraday's Law)
- The faster the motor rotates, the probability that the magnets will be fired increases (Physical Principle: Centrifugal Force)
- If we increase the separation between the motors, we can turn them easily, however, if we increase the speed the synchrony between them is broken.
- If we reduce the separation between the motors, it is hard to start them, however, the synchrony is maintained at high speeds.
RECOMMENDATIONS FOR THE NEXT STAGE (II):
- Use Motors (As Generator) Brushless Outrunner type less than 1000KV (KV = RPM / Volt), this allows us to generate more voltage with fewer revolutions.
- To rotate the group of Generators, use an Outrunner type motor, but greater than 2000KV, this allows us to have more revolutions per minute with less voltage supply.
- Use a microcontroller (Arduino / Raspberry PI) to control the motor speed and therefore regulate the desired output voltage.
- Obtain the graph of Temperature of the motors against the RPM, in order to obtain the optimum speed of operation and in case of being required to provide cooling to the motors. (In case of criticism, Brushless Inrunner type motors for boats can be used. This type of motors comes with a water cooling circuit).
Step 8: FINAL COMMENTS
In this project I use a CD / DVD engine as a generator, which according to its data is a 12 V / 1 Amp motor, which gives us a motor with a capacity of 12 Watts.
If the new model aircraft engines are used, impressive results can be obtained. There are small engines with a power of several hundred Watts. If we put them together, we can energize an inverter unit of up to 1500 Watts easily. In addition to allowing us to change the configuration of the electrical circuit to adapt to the needs of the Power Inverter. If these types of motors are used and the motors are placed in the form of a ring, so that we can electronically control their position during the start and stop of the system, we can obtain a highly efficient system.
We can use this type of Power Generators in the near future as an increase in the flight time of our Quadcopter's.
Step 9: REFERENCES
Participated in the