In India, there are lots of people who still prefer trains to travel and spend days together to complete their journey. Most trains usually don't provide electricity even though there are charging sockets available. Even if they do, it is seen that such a charging facility takes a longer time than usual to fully charge the cell phone. Sometimes the passengers can even be seen fighting for charging their cell phones if there are less number of charging sockets available. I've myself witnessed people waiting at every coach's doors to get a chance to charge their phones.
Click here to see the proof for a live example! :-p
To this problem, a common temporary solution may be a to use a typical PowerBank which doesn't last longer and need to be charged again. Solar cells are next preferred ones but are unreliable at most times and they are not economical too. So my unique solution to this problem is to use a Wind Generator. Since the trains run at least for 20 hours a day with a minimum speed of 30kmph, the wind hitting the windows can be converted into valuable electrical energy and hence charge our cell phones.
The application of this 5 watt wind generator is not just limited to a moving train but is immense as it can easily be used while travelling on any vehicle like bicycles, buses, motorbikes,recreational vehicles..etc.
In this simple Instructible I'll show you how to make one for yourself with the easiest method possible.
Step 1: Materials Required
If you dont have a 3D Printer
>>Epoxy Putty like Mseal
Step 2: Polarity Test of the DC Generator
(Skip this test if you already know the polarity of the generator)
The polarity of the generator varies along the direction of rotation or the direction at which the propeller rotates. With the action of wind, some propellers are designed to rotate in clockwise direction and some are designed to rotate in anticlockwise direction.
Simply Connect the terminals of the propeller coupled generator to the respective positive and negative terminals of the voltmeter and conduct the test.
Just give a blow manually to the propeller such that it rotates. Simultaneously observe if the voltage read on the voltmeter for a positive or negative voltage.
>>If the voltage read is positive, then the terminal of the generator connected to the voltmeter positive is positive and the other terminal is negative.
>>Else if the voltage read is negative, then the terminal of the generator connected to the voltmeter positive is negative and the other terminal is positive.
Refer the video for demonstration of the polarity test.
Step 3: Schematic/Circuit Diagram and Working
The total Circuit involved with the wind generator is shown in the above pictures.
Whenever the fan rotates, an emf will be generated. The output voltage is not constant. But in order to charge our phones, a constant voltage is necessary. For that we need to use a voltage regulator of constant 5v output. Even the output current through the voltage regulator is limited to 1Amps, and thereby making this wind generator a 5W energy source. There may be noise in the output, to mnimise the same, shunt capacitors are use. You can either use two 33 micro Farad capacitors or two 22 microFarad capacitors across input to ground and output to ground terminals. Finally a micro usb cable that is compatible with your phone can be connected to the output terminals to charge the phone.
You can either rig up the components on a perforated board or can even design a simple PCB, etch it, place the components and mount it on a DC generator directly.
Step 4: 3D Printing (You May Skip This Test If You Dont Have a 3D Printer)
Some parts of the above 3d structures are used from ready made models available on Thingiverse and assembled by me through Blender software. You must edit the parts because the size of your DC motor may vary with that of mine. The main intention of myself uploading the 3d files are to provide you an access to the files used for my idea. I have attached the blender files in case you need to edit it. If you have used a motor with an outer casing of 25mm diameter., then you can go ahead and print all the parts separately and join it as shown in the above figures. I have used fevikwik to join all the parts.
After assembling everything, place your generator in the cylinder and attach a fan to it from the front. Since I have made a PCB, I have directly mounted the PCB to the generator. You can even attach the rigged up perforated board circuit which was shown in the previous step to the output of the generator and complete the working model.
Step 5: If You Don't Have a 3D Printer
In case you don't have a 3D printer, then you can make an epoxy adhesive to attach a metallic clip to the generator like the one shown in the above picture and allow it to dry n .
After attaching the steel clip, connect the circuit which was shown in the previous step to the output of the generator and complete the working model.
Step 6: Mounting Methods
This wind Generator can be Mounted on the rods of any moving vehicles regardless of the direction of movement of the vehicle or the window seating arrangement of the passenger in trains or buses.
For instance I have shown how to mount the wind generator in various ways.
Step 7: Conclusion
>>This working model has been tested and found to be working successfully while travelling on a bike and bus with speeds no less than 40kmph. However, I didn't find the necessity to travel in trains so I could not experiment it personally and record the video there.
>>The Working video of the same while travelling in a scooter has been uploaded.
>>Feel free to ask any kind of queries. I assure you a reply to it as soon as possible.
>>My sincere thanks to all the staff of BMSCE Research and Development team for granting us the permission to use the 3D printer and providing other technical support.
>>Please vote my instructible for the contest "BRAVE the ELEMENTS" if you liked it. :)