User:MundaneUser/enes100/My Work

Wind Turbine

Write problem/project Goal
To design and construct a functional scalar wind turbine
 * | Funtional Wind Turbine Prototype

My First Task
To charge and test batteries that will be used for power storage and to research inverter designs and create a schematic for an inverter.

Summary of actual work over first week
I had planned on charging a 12v battery with a trickle charger. The trickle charger was unsuccessful in charging the battery. I had also planned on creating an inverter schematic. I was able to recreate a schematic but I was not able to understand exactly how an inverter works. To fully grasp the concept I must learn how exactly a transistor works.

Week1 Narrative
I began drawing up ideas for the Turbine design. I analyzed contemporary designs both professionally manufactured and home-made to get a starting point. Then I referenced available tools and materials to come up with a strong, effective, simple design.

My Second Task
To test more batteries and to disassemble a computer fan which I believe is from a power supply.

Summary of actual work over second week
All batteries tested (two 12V and one 6V) and successfully charged. I had a minor mishap with the fan when I took it apart.

Week2 Narrative
I disassembled a small computer fan in order to scavenge the fan blades. During the removal of the shaft I cracked a fan blade. I proceeded to disconnect the DC motor from the fan blades to understand how to get the next one apart because this set of blades was broken. I roughly documented my steps at home; I planned on disassembling another on Tuesday with a full detailed tutorial to show to my team. The reasoning behind my detailed tutorial following my initial attempt is so that I understand how to properly take it apart without breaking any blades during the detailed documentation.

My Third task
So far the plan is to research a way to have two separate LED's turn on at different amperages. For example, when our motor is only producing 2V a yellow LED is emitting and when the generator is producing 3.86V (max V from generator spun with an air compressor @ 100PSI-tank pressure and ~35PSI-output pressure) a second LED is emitting as well or when the HI-V is being produced the LOW-V LED is off. I am not sure which is possible or which is less complicated. The idea is still very rough, hopefully through some thorough research and progression through my Principles of Electrical Circuits text, I may arrive at a solution. I have been drawing up circuit diagrams for my goal: I am postponing the idea of a HI-V and a LOW-V LED display. I have transferred my focus to producing a parallel circuit that uses a pull down resister to regulate voltage and current to my LED and on the other leg of the circuit using the amperage to charge a battery. With 150mA I should be capable of charging a small 1.6V NiCd battery or a lithium ion battery (a cell phone battery). In order to charge a cell phone battery I will take a Micro-USB connector, sever the wire and direct wire it to my circuit (assuming that I have the proper resistance within the circuit; this is achievable by deriving my resistor value by calculating my desired Voltage and Amperage).

Summary of actual work over third week
The original plan fell through completely because I destroyed our miniature prototype fan blades during a test. The blades came off the crankshaft during the test for two reasons: first, because I had not fully secured the blades to the shaft; second, because I applied maximum (35) PSI from an air compressor. Instead I had to scale up our project design incorporating the DC motor we scavenged from a radiator fan during week 1. Because I had to redesign a whole new prototype, I have postponed my LED circuit testing. I have also had to retest motor output using a leaf blower instead of compressed air. Instead of redesigning a base and shaft I scavenged a pipe cemented into a plastic bin and used that for the main shaft and support.

Week3 Narrative
I designed new motor mount for larger motor on the new shaft. My plan is to use a dremel with a cutting wheel to make slits equal to the fins on the motor, use a sanding wheel to create a cup to sit the motor in, and drill two opposing holes and run a bolt through the pipe and the motor.


 * Because I am working with a larger motor with higher voltage and current output I have redesigned my test circuit to include greater resistance so that we are not flowing too much current through the diode. In order to calculate the resistance necessary for the circuit I had to do some LED testing to determine their optimum voltage and current, turn on voltage, and what current exceeds the desired range.


 * During a test of the 12V DC-Motor, using a 1HP electric leaf blower, we were able to produce 8.1V maximum. Using this information and an LED Calculator I was able to determine that my circuit would need 330 Ohms total resistance. From that I was able to design a simple LED circuit with 330 Ohms resistance incorporating an ammeter and voltmeter to measure our motors output. During the creation of the circuit, I was unable to find a 330 Ohm resistor so I had to improvise by soldering a 220 Ohm resistor and a 110 Ohm resister in series. Finally, I attached the test circuit to the wire harness that was part of the DC-Motor assembly. Next step was to test the circuit while attached to the generator. I decided to use ambient wind speed and see if I could get usable power. During the test I was unable to get a voltage or amperage measurement. I later realized that my circuit resistance was so much that the amount of current created from the wind was not great enough to forward bias the diode. This caused my circuit to be open and the result was no Amp or Volt readings. Next, I decided to use the 1HP leaf blower in addition to the ambient wind speeds. Before I could take a measurement, the additional wind pressure caused the long cardboard blades to collide with the shaft. I propose that I cut the blades in half and increase our number of blades to 8.


 * Next, I planned on using a 12V cigarette USB adapter to charge a cell phone using a traditional USB to Mini-USB cable. In order to do so I severed the cables leading to the adapter and soldered them directly to the wire harness. During the test, I was unable to produce a charge at maximum output with two leaf blowers. I tested the circuit directly with a variable power supply. During the test I heard a large popping noise. I checked the fuse to see if it was the source of the noise, it was not. I'm still not sure what it was but I did discover that I had reverse wired the circuit from the harness to the adapter.

My Fourth task
Over the next week I plan on testing, finishing, and implementing my charging circuit as well as testing my LED voltage detector circuit. Also, I plan on redesigning and constructing a new fan. Lastly, I will record a video tutorial on how to disassemble a PC fan (will include my documented steps from earlier in the project) and a video tutorial on disassembling a radiator fan and motor.

Summary of actual work over fourth week
I had originally planned on rewiring the wire harness and USB adapter circuit. The adapter circuitry was destroyed resulting from the reverse biasing of a capacitor. This caused the capacitor to burst and was the source of the loud popping noise during the initial test. I eliminated the possibility of fuse failure because the fuse was still measuring voltage, proving that it remained a closed circuit. I was unable to find an identical PC fan so I've decided not to create a video tutorial. Also, the PC fan is obsolete within our new design specifications. Lastly, I have successfully created and tested an LED voltage detector circuit. I am working on a way to implement the design onto the main chassis of the turbine.

Week4 Narrative

 * In an attempt to reduce time spent soldering and hard wiring my circuits together, I began experimenting with breadboards. Since I am not familiar with wiring circuits on breadboards I began with some simple tests. First, I wired a single LED using 4 jumpers. One from the power source to the positive column, one from the power source to the negative column, then a positive and negative to power and return. I later realized that the same task can be accomplished using only two leads, directly from source to row. Now that I have understood how to supply power via jumpers on a breadboard, I tried wiring two LEDs in parallel. To connect them in parallel I set my positive row on row 15 and my negative (return) on row 18. Then I attached the LED's Anode to the positive row (15) in column A and the cathode on the negative row (18) in column A. The next LED I set had a 1 column 3 column gap on the board so its anode was in row 15 column E and its cathode was in row 18 column E. Remembering that series circuits divide voltage and parallel circuits divide current, using a variable power supply I was able to see that the circuit operated at 1.8V at 40mA. This means that the current doubled in order to power both LEDs meaning that the circuit was indeed parallel. Next, I wired three LEDs in series and I tiered each one cathode to anode. This circuit took 5.4V at 20mA to power all three LEDs. Because the voltage was divided, the circuit was wired in series.


 * Next, I placed a 1 Ohm resistor in parallel between my LEDs causing the first LED1 to turn off and LED2 to remain on. This is because the current flows to the path of least resistance and the resistor caused the current to bypass LED1 because it was not forward-biased and therefor had greater resistance. In another test, I had three LED's wired in series, when a parallel resistor is introduced between LED2 and LED3, only LED3 turns on. Using the same series LEDs, if the resistor is introduced between LEDs 1 and 2, both 2 and 3 remain on.
 * ParallelLEDCircuits.jpg
 * Continuing on my train of thought, I decided to wire my side-by-side test circuits together in parallel and see the outcome. Only LED 1-2 was functioning. This illustrates the same concept as the first two tests using a parallel resistor. This lead me to the conclusion that I would need an initial pull down resistor before the LEDs to draw enough current to forward bias each leg of my circuit.


 * Using the same LED Calculator as before, I calculated my initial test circuits resistor values:

I would need a 100 Ohm resistor in order to drop the voltage down to 1.8V. I will also need an initial pull down to draw current through the initial LED. Then using a variable power supply set to 2.7V, I lit the LED. This was a fast test in order to check my resistors and LEDs.
 * I've added another leg on to the original circuit in an attempt to regulate the turn on of the LEDs at varying voltages. I attached the positive and negative leads on the breadboard to the variable power supply. First, I increased the current just enough to allow voltage flow, then I adjusted the voltage regulator until my first diode turned on. Then I switched the display to amps and measured the current flow. Next, I switched the display back to volts and adjusted the voltage regulator until the second diode turned on. The circuit worked! I've recorded the results below.

Because this double-LED circuit is designed to divide 3.2 volts, I must increase the number of LEDs to 3 in order to handle 6V. I may even need to include a fourth LED.


 * I've added another leg and noticed the same pattern of turn on as with two. What is interesting, and possibly incorrect, is my data. I've noticed that the middle LED requires 17mA to turn on while the third only requires 5.2mA. I may have misread the meter so I will have to retest the circuit and make sure my data is accurate.


 * Another interesting characteristic of my circuit is that it is only capable of soft-switching. Meaning that the LEDs do not turn on at full brightness, they fade in and out depending on the voltage. My next goal is to solder a hard-wired LED voltage detector on to the wire harness and connect it to the wind turbine generator.

Complete Project Page
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