Interim Design Report
Contents
1. 30 Back EMF c T V I 31 Housings and MountingS ae 35 sig bolsa ENS 35 Mem c TREE a NE 36 Waterproof Electrical Housing seen 38 ELECTRICAL DESIGN 39 uu y He M M 39 DC to DC Step Down 41 Power Status Indicatlors 45 Battery Status MIKA T 47 donem H 49 Charge Regulator sni ee een 52 ee 56 AquaJolt PROJECT MANAGEMENT us u puna u h Sma ass 60 Budget Analyg lt Ssu uu lana 60 Work Breakdown Structure and Schedule Analysis 68 APPENDIX LTC3789 DATASHEET eurer nn A APPENDIX B MAX6458 6459 DATASHEET B APPENDIX C MAX8212 DATASHEET nana tau nta tao nna und n tun hann a cu C APPENDIX D LM350 DATASHEET u D APPENDIX E BATTERY E APPENDIX F MAIN SHAFT BEARINGS DATASHEET F APPENDIX G INTERMEDIATE SHAFT BEARING DATASHEET G APPENDIX SHAFTS DATASHEET_ III a H APPENDIX I SPROCKETS DATASHEET a A teu Rain ER aS a2. 18 97 595 89 Mechanical Budget Quantity 4 NO O PN P 100 Notes Includes screw nuts 1346K33 McMaster Carr 6793K23 McMaster Carr 6793K11 McMaster Carr 6793K9 McMaster Carr 6261K171 McMaster Carr Already Own 6384K79 McMaster Carr 60355K707 McMaster Carr 6061K331 McMaster Carr Tractor Supply Company Lowe s 3018T14 McMaster Carr check Lowe s Lowe s check for smaller sizes Lowe s Wholesale Marine NI shipping Lowe s Lowe s expressPCB NI shipping Lowe s Lowe s Lowe s Lowe s Order Status Purchased Purchased Ordered Ordered Ordered Ordered Ordered Purchased Ordered Ordered Ordered 1 Purchased Josh Purchased Ordered Purchased Purchased Purchased Purchased purhcased Purchased Purchased Purchased Purchased Tot Cost 25 86 1 71 34 87 31 46 5 27 5 07 33 57 0 00 24 62 22 62 6 59 50 00 12 32 8 00 9 47 15 98 31 96 4 47 0 00 50 00 42 00 51 00 5 20 94 88 10 00 18 97 67 AquaJolt Budgeted Spent Electrical 273 91 Electrical 273 91 Mechanical 595 89 Mechanical 454 89 Total Cost 869 8 TotalSpent 728 8 WORK BREAKDOWN STRUCTURE AND SCHEDULE ANALYSIS Fall Semester For the most part the project is on schedule and in some areas is actually ahead Generator testing originally planned for the spring was started in the fall in order to help finalize the wh
3. GEOMETRIC EXPLANATION OF VARIABLES IN TORUS VOLUME FORMULA 21 AquaJolt For the four tubes originally postulated to be able to support the platform each one has to displace 0 025 m of water The tubes selected were 14 inch diameter lawnmower tubes Individually they were found to displace 0 01 So the design was changed to include ten tubes five on either side This increases the overall cost of the floatation but still stays well within budget As this weight was the worst case scenario the overall design and budgeting only includes six tubes The floating platform consists of a wooden support structure that is topped with plywood sheeting as seen in Figure 13 Marine plywood that has been treated for water resistance was chosen as the sheeting material because of its unique properties Plywood is cheap relatively lightweight and easily obtained both domestically and in economically depressed regions Figure 13 shows the decking and framing FIGURE 13 FLOTATION DEVICE CONFIGURATION The tubes will be secured to the platform using short lengths of rope attached to the wooden support structure using large staples Figure 14 shows the floatation deck as seen from the bottom The red lines represent 1 amp 40boards All other supports are 10X20 The design of the support structure allows for each tube to have a compartment to help further secure the flotation devices in place There are not any supports extruding downward on
4. Two of these will be used in our system one to measure the power from the battery and one to measure the power coming straight from the generator Then based on the indication from the LEDs the user can flip a switch to select where to draw power from The typical configuration for window detection is shown in Figure 44 Vcc Vec L TM NEN Lu gt S ur I 4 R1 e nma nmal lt lt lt lt 5 lt lt gt gt 3 e Z lt gt ees owe 2 FIGURE 44 MAX6458 WINDOW DETECTION CONFIGURATION This IC contains an internal hysteresis option of 5 This radds noise immunity to the voltage monitors and prevents oscillation due to repeated triggering when is near the threshold trip voltage Page 9 MAX6458 Datasheet Appendix B MAX6458 6459 Datasheet Based on page 11 of the MAX6458 Datasheet Appendix B MAX6458 6459 Datasheet the values for the resistors were calculated as follows Choose a value for Rrora the sum of R1 R2 and R3 Because the MAX6458 MAX6459 have very high input impedance RTOTAL can be up to 5MY 46 AquaJolt For our system with a 5 hysteresis 1 228 V 1 167 V 14 5 V Vrrip ow 11 5 V Set Rrora 55 5 R3 4 7 R2 1 22 R1 49 5 BATTERY STATUS INDICATOR This system shows the capacity of the battery that is l
5. there is no output Battery The battery will store the power produced by the generator INPUT DC Power 0 14 V 0 3 A OUTPUT DC power 0 12 V 0 10 A Generator Power Status Indicator The generator power status indicator will determine if the inverter is being supplied sufficient DC voltage to operate 10 15 VDC It will use comparators to determine if the voltage is within the specified range If it is a green LED will turn on If not a red LED will turn on This will let the user know if it is okay to turn on INPUT DC Power 0 14 V 20 mA OUTPUT Green or Red LED will be illuminated DC Power 0 V 1 mA 0r 11 5 14 5 V 10 mA 12 AquaJolt Battery Power Status Indicator The battery power status indicator will determine if the inverter is being supplied sufficient DC voltage to operate 10 15 VDC It will use comparators to determine if the voltage is within the specified range If it is a green LED will turn on If not a red LED will turn on This will let the user know if it is okay to turn on INPUT DC Power 0 14 V 20 mA OUTPUT Green or Red LED will be illuminated DC Power 0 V 1 mA or 10 5 12 V 10 mA Inverter The inverter will take the DC output of the battery and convert it to AC then send it to the user This includes an 80 efficiency consideration INPUT DC Power 10 15 V 0 10 A OUTPUT AC Power 120 V 0 800 mA 60Hz ORGANIZATION AND MANAGEMENT The AquaJolt team consists of two mecha
6. www digikey com www digikey com 33973 2 0 12 0 24 Y 697531 2 0 12 0 24 Y Section Total 0 78 Battery Status Indicator Manf Part Quantit Unit Total y Price Price MAX6459 5 Sample 0 LM10841S 5 0 NOPB 1 1 33 1 33 SN7404NE4 ND 1 0 87 0 87 CMF115HFCT ND 1 0 17 0 17 RNF14FTD44K2CT ND 2 0 15 0 3 690697 3 0 03 0 09 VB3G40ND 1 0 8 0 8 P91BACT ND 1 0 09 0 09 P20 0CACT ND 10 0 15 1 5 690620 1 0 03 0 03 SFR2500001050FR50 1 0 18 0 18 0 RNF14FTDD5K11CT 1 0 15 0 15 ND ALSR5J 700 ND 1 1 55 1 55 RNF14FTD41K2CT ND 1 0 15 0 15 In Lab In Lab Ordere Receive d d Y N 2 5 Y In Lab Y In Lab Y N Y N Y In Lab Y N Y N Y N Y In Lab Y N Y N Y N Y N 64 AquaJolt 100 Res www jameco com 690380 1 0 03 0 03 Y In Lab 2 Res www jameco com 690937 1 0 03 0 03 Y In Lab 4 7 Res www jameco com 691024 1 0 03 0 03 Y In Lab 1300 Res www digikey com P130BACT ND 1 0 09 0 09 Y In Lab Yellow LED WWW jameco com 334108 3 0 12 0 36 Y In Lab 65 AquaJolt Part Op Amp Nor Gate Zener Diode 13V Zener Diode 36V Mosfets 120VAC 60Hz Trans 22k resistor 27k resistor 1 Res 47 Res 3 3kQ Res 2 7kQ Res 1000 Res 1 Res 20 Res 0 1pF Cap 1pF Cap 220pF Cap 1N4148 Manufacturer www jameco com www jameco com www mouser com www mouser com www futureelectronics com Scrap Material WWW jameco com www jameco com www jameco com www jameco com www jameco com www jame
7. 4096 efficiency loss from velocity of the water to velocity of the wheel INPUT Water 0 5 m s OUTPUT 0 38 rpm 0 1750 N m water 0 3 m s Gear System The torque and rpm of the turning mechanism will be sent through a system of gears to increase RPM at the cost of torque The desired ratio is anticipated to be at least a 10 1 gearing ratio This also includes a 979 efficiency consideration INPUT 0 38 rpm 0 1750 N m OUTPUT 0 369 rpm 170 N m Output Shaft The shaft transmits the altered torque and rpm to the generator The DC power generated is taken experimental data shown the section labeled fBack EMF INPUT 0 369 rpm 170 N m OUTPUT DC power 0 65 V 0 4 A DC to DC Step Down This section will take the DC power from the generator and drop it down into a range that is acceptable for the battery and the inverter INPUT DC Power 0 65 V 0 4A 11 AquaJolt OUTPUT DC Power 0 14 V 0 5 A Charge Regulator This device will prevent the battery from becoming overcharged It allows power to pass through until the battery is fully charged Once it is charged the charge regulator stops the battery from charging In addition it also keeps the battery from returning charge to the generator when insufficient torque is applied to the wheel It also has a current regulator to keep the current at a safe level for charging the battery INPUT DC Power From DC to DC Step down 0 14 V 0 5 A DC Power From Voltage Mon
8. M6 x 1mm A0 dia 10 15 mm Min 2 84 1 995 2 000 7236 mm 50 67 50 8 FIGURE 25 DIMENSIONS OF THE DC 540 Back EMF One issue that has not been thoroughly addressed by previous generator projects is back electromotive force This physical phenomenon occurs inside of any current producing alternator This force acts against the current being generated which results in a physical torque that needs to be overcome by whatever turning mechanism is in place None of the specifications listed by Presto Wind or WindBlue gave any information on how their generator responds to different current levels This is most likely due the fact that the current output of the generator the driving force in the creation of back EMF varies widely depending on the battery used the characteristics of the circuit and the charge already present in the battery Since the DC 540 was on hand it was possible to conduct experiments on it to determine its traits and design for them accordingly Figure 26 shows one of the two testing setups used to determine back EMF present at a given time 31 AquaJolt Generator FIGURE 26 EXPERIMENTAL SETUP TO DETERMINE The experiment was carried out using a wooden pulley with a radius of about 0 03 m This pulley had a groove carved into the edge in order to give the string a more secure winding place The generator was then clamped in place and different weights were attach
9. is supplied to the battery Since the charge regulator requires minimal and readily available parts it was constructed on a bread to test its compatibility with the voltage monitor Figure 55 Charge Regulator Voltage Monitor FIGURE 55 CHARGE REGULATOR CONNECTED TO VOLTAGE MONITOR The compatibly was tested by connecting the devices to a variable power source One was set a 14V to simulate the output of the buck boost regulator A separate power source was connected to 54 AquaJolt the voltage monitor to simulate the battery This voltage was varied while the output of the charge regulator was measured Figure 56 Voltage Monitor and Charge Regulator Compatability Test p 5 gt 2 Simulated Battery Voltage V FIGURE 56 VOLTAGE MONITOR AND CHARGE REGULATOR COMPATABILITY TEST The voltage monitor and charge regulator worked exactly as expected When the simulated battery voltage was less than 12 5V the output voltage from the charge regulator was 14V which will be sent to the battery to charge it When the simulated battery voltage was raised above 12 5 the output voltage from the charge regulator was on the mV range This system will work very well to not only charge our battery but also to prevent it from over charge Also in the section a current limiter is used to protect the battery from to being charged at too high a rate The battery we have chosen has a maximu
10. is that formulas for complex bodies do not exist This approximation also maximizes the area making this a true worst case scenario calculation The final value for the drag force will most likely be less than these calculations predict for a flat plate can be found via Figure 17 and the equations following it 400 o SEE 2 I LII HILL LI 1 imd I e 6 mmi TEES i 4 DESEE 4 I Pi ze SIT RI osE E HE e as i III T Sum 111 2 77 0 SIE ass I EH R 107 10 10 10 10 104 105 106 FIGURE 17 DRAG COEFFICIENTS FOR SPHERES AND CYLINDERS GIVEN A 05 NUMBER 5 1 10 4980000 Since the Reynolds number is greater than 10 this is turbulent flow so the above graph is used to find a value for the coefficient of friction 0 4 1 2 20 4 80 2 211000 35 1000 25 AquaJolt This force while considerable is also a worst case value Also this force is being received by two anchors so each one only sees 500 N of force The Fluke anchors should be able to handle this load The anchors will be secured on the platform at both corners with eyebolts and secured at approximately a 35 angle from the platformG centerline to ensure both that the device stays straight in the river and that the forces acting on the ropes is low since placing anch
11. models were the WindBlue DC 540 readily available and the Presto Wind M 12 Each model had its own advantages The M 12 generator came with a number of different stators allowing for multiple set up options to maximize power output It was also slightly lighter than the DC 540 and was rated to produce 12 volts at a lower overall RPM However neither generator included any sort of data on start up torques nor back EMF created at varying RPM for different loads Without knowing the torques that the generator would need to produce useable power the design for the waterwheel would be guesswork at best The DC 540 also includes a brushless design and a built in rectifier Another advantage held by the DC 540 was that as it had been used previously it had been fbroken ing avoiding the period in a new generator amp use life when power output is lower than its specifications might indicate The DC 540 generator was eventually selected due to the fact that it was on hand for immediate testing in order to determine its characteristics Figure 24 and Figure 25 show the specifications given by the manufacturer for the DC 540 Model DC 540 PMA Output a 8 8 Volts Amps 60 50 4 30 20 65 8 750 1000 1250 1500 1750 2000 RPM FIGURE 24 MANUFACTURER S SPECIFICATIONS FOR DC 540 GENERATOR This data was gathered by the manufacturer and assumedly presents the best case performance ofthe generator 30 AquaJolt 12 24 Th d
12. on a reliably consistent source of renewable energy Hydroelectricity is an environmentally friendly perpetual source of energy that has less risk than fossil fuel or nuclear power generation Many developing nations do not have the capability of generating power on a large enough scale to deliver a constant source of electricity to each home Most homes in those nations are not connected to an electrical grid like we are accustomed to in the United States However people in this part of the world still own small electrical appliances such as cell phones and radios With the increasing technological advancements in the cell phone industry phones are capable of connecting these people to the rest of the world in a way that was previously impossible However it is difficult for them to find places to charge these devices consistently A device that could generate enough electrical energy to power these small devices along with any other small appliance on hand would be extremely useful Our portable hydroelectric generator seeks to address some of the electrical generation deficiencies faced by many people in developing nations across the world The device will utilize hydroelectric generation methods to power small personal appliances such as cell phones and radios The device would be placed in a moving body of water and be able to safely generate electricity that can be sent directly to the appliance or to a battery for later use The AquaJolt por
13. support Another support method considered was a series of mounting poles that would be secured to the bottom of the river bed for the unit to rest on However this limited both the water depth and the riverbed material that the device could operate with The final floatation method chosen was to use tire inner tubes similar to the one in Figure 11 to provide the floatation These tubes while more fragile than metal counterparts have the advantage of being both lightweight and collapsible for easy transportation An arrangement with multiple inner tubes offers a high degree of stability to prevent the device from tipping while in use The inner tubes can be inflated with a simple hand pump that will be included with the final product 20 AquaJolt FIGURE 11 TYPICAL INNER TUBE DESIGN AquaJolt will be suspended in the water by inner tubes like this each secured under the main platform The amount of flotation needed was determined by using the maximum estimated weight of the completed device or 100 kg via the following formula In this formula represents the mass of the object is the density of the fluid and is the volume displaced The amount of water that needed to be displaced by the floatation mechanism was found as follows 100 1000 H 0 1 The volume of a cylindrical hoop or a torus is found via the following formula 2 The variables in the formula above are explained by Figure 12 L FIGURE 12
14. was designed using the dimensions of the generator in order to create an optimal housing size The sides are held together by epoxy to ensure a watertight seal The generator is connected to the onshore station via a garden hose attached to the back of the Plexiglas box This ensures that the wires are protected from both moisture and floating debris This component is shown in Figure 32 Hose Coupling FIGURE 32 GENERATOR HOUSING CONCEPTUAL LAYOUT 36 AquaJolt The completed conceptual design is shown in Figure 33 FIGURE 33 THE COMPLETED CONCEPTUAL MODEL OF THE FLOATATION PLATFORM AND ITS SUBSYSTEMS 37 AquaJolt Waterproof Electrical Housing All the electrical parts and components will be kept in water resistant housing for protection as shown in Figure 34 Having all the electrical parts in the housing will make transportation easy and safe The housing will be water resistant and strong enough to handle the weight of all components The whole size of the housing will be determined by the size of the individual components The largest component will be battery with dimensions of 151mm 5 95 x 65mm 2 80 x 111mm 4 48 and has a mass of 3 3 kg The next largest component is the transformer used in the inverter with dimensions of 105mm 4 125 x 89mm 3 5 x 97mm 3 8125 Outlet FIGURE 34 WATERPROOF ELECTRICAL HOUSING One side of the housing will have an AC outlet mounted on it so that the u
15. 2 FIGURE 59 120V 60 HZ TRANSFORMER The inverter will convert the incoming DC into AC and then it will step up the resulting AC to the main voltage level using a transformer The DC from the 12V 10Ah lead acid battery will be converted into by using a pair of power RFG50NO06 N Channel Power MOSFETS as seen in Figure 60 acting as efficient electronic switches By using MOSFETS very little power is wasted as heat because when they are off they are virtually an open circuit and when they are on they are close to a short circuit Dual Precision Op Amp LT1013 CMOS NOR Gates and the transistor shown in Figure 60 form a voltage controlled oscillator of which the frequency is adjusted with the 25K ohm pot This will give a square wave output voltage Figure 61 The buffers drive the MOFETS out of phase with each other The 13 volt zeners stabilize supply voltages and limit signals while the 36 volt zeners limit spikes from the transformer 57 AquaJolt R6 50965 5 v2 Key A d VDD Jt ni 7 R8 T 22 ls wet SWITCH 3 R17 D10 po sv 13 Y 220pF 22kQ VD Switch 2 switch4 2 D11 Q1 Q R7 2N3904 WN 1 R10 50 V 22 0 Switch 1 1 R14 SWITCH 3_1 L Q2 i 6 ee Switch 2 1 D5 switch4 1 gt 3 2 FIGURE 60 INVERTER DESIGN 58 AquaJolt Vo Ita Time FIGURE 61
16. 42 respectively 1 0 0ms 0 1ms 0 2ms 0 3ms 0 4ms 0 5ms 0 6ms 0 7ms 0 8ms 0 9ms 1 0ms FIGURE 39 BUCK BOOST REGULATOR OUTPUT 10V INPUT 43 AquaJolt 0 0ms 01 0 2ms 0 3 0 4ms 0 5 0 6ms 0 7 0 8ms 0 9 1 0ms FIGURE 40 BUCK BOOST REGULATOR OUTPUT 20V INPUT 1 0Y 1 0 0ms 01 0 2ms 0 3ms 0 4ms 0 5ms 0 6ms 0 7 0 8ms 0 9ms 1 0 9 FIGURE 41 BUCK BOOST REGULATOR OUTPUT 30V INPUT 44 AquaJolt 1 0 1 0 0ms 0 1 0 2 0 3ms 0 4ms 0 5ms 0 6ms 0 7 5 0 8ms 0 9ms 1 0ms FIGURE 42 BUCK BOOST REGULATOR OUTPUT 40V INPUT From these plots we can see that the buck boost regulator operates as intended This will suit our application very well POWER STATUS INDICATORS These sections determine if there is enough power coming into the inverter to be able to operate it properly The MAX6458 Voltage Monitor displayed in Figure 43 is used to accomplish this HYSTERESIS OPTION Uv UNDERVOLTAGE DV OVERVOLTAGE FIGURE 43 MAX6458 FUNCTIONAL DIAGRAM This voltage monitor measures an input voltage and checks to see if it is within a preset window For our applications the window is 11 5 V to 14 5 V If it is within this window it outputs the voltage This will light up a green LED indicating that there is appropriate power If it is outside of 45 AquaJolt this window it will output a logic low 0 V This will then be used to light a red LED
17. AQUAJOLT 12 7 2011 Interim Design Report Taylor Gammon Josh Pilgrim Mary Samoei Kendall White AquaJolt TABLE OF CONTENTS REQUIREMENTS SPECIFICATION ituri toan eon 3 97 0 eR cU 3 Mission Statement ea 4 BI co me 4 Operation sain ia 4 Customer Ne dsS E D om 4 Teehnical SSC CONS MR o Oo S 5 Needs Metrics Matrix seen 6 Testing Fan 7 Implementation Considerations 7 SYSTEM DESIGN 8 Background cosas u ur a 8 System OvervieW m ee ee 8 Functional Decomposition of BIOCKS eter neret cte 9 Organization and Management r 13 MECHANICAL DESIGN 5 22 a nta andan ttd numi qu 14 Turning Mechanism 14 Water When ua a ee ene eee ene ee 14 Power arid year ee ee 19 Flotation Mechanism E OO eee ee eee 20 trc nee ee 23 tcu ae 27 Bu EC u ae 29 Generator SEIECION
18. ND Our world is becoming increasingly mobile As cellular phones continue to increase in versatility and range a demand for a reliable source of power in remote locations continues to grow No group is more interested for decentralized energy than are developing countries As of 2009 over 1 4 billion people primarily living in Africa and Asia have little to no access to electricity Even if the people of these nations have been able to procure some sort of conventional generator they soon find themselves forced to rely on fossil fuels if they desire an electricity source These generators possess a number of inherent flaws that limit their usefulness such as the cost and weight involved in transporting fuel long distances over potentially difficult terrain The obvious solution to these issues is to use a generator that is powered by a renewable energy source such as solar wind or hydro power However solar and wind power both rely heavily upon weather conditions of a given area in order to produce a usable amount of electricity Hydro power possesses a unique advantage if the body of water is chosen judiciously hydro power can be considered a constant source of power SYSTEM OVERVIEW Aquajolt the portable hydroelectric generator would answer all of these problems Since the residents of these countries possess little in the way of what most Westerners would consider large appliances the power output of such a device would not have to
19. SQUARE WAVE OUTPUT VOLTAGE 59 AquaJolt Project Management BUDGET ANALYSIS Part LTC3789 20 Res Res 10m0 Res 120 Res 1 Res 1000 Res 4 7pF Cap 10pF Cap 0 1pF Cap 0 001pF Cap 0 01pF Cap 270pF 22uF Cap 2 2uF Cap Manufacturer www linear com www jameco com www jameco com www digikey com WWW jameco com www jameco com WWW jameco com www jameco com WWW jameco com www jameco com WWW jameco com www jameco com www digikey com www jameco com www jameco com Electrical Budget DC to DC Step Down Manf Part LTC3789 691171 691462 630HRO10E ND 691366 690865 691340 330465 29891 609043 33260 546257 PD11200 NP 158327 93731 Quantity Unit Price 1 Sample 1 0 03 1 0 03 2 0 52 1 0 03 1 0 03 2 0 03 1 0 05 1 0 06 2 0 09 1 0 07 1 0 07 1 0 48 1 0 09 1 0 08 Total Price 0 03 0 03 1 04 0 03 0 03 0 06 0 05 0 06 0 18 0 07 0 07 0 48 0 09 0 08 Ordered Received In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab 60 AquaJolt BAT54 Diode www mouser com 511 2 0 16 0 32 Y N BAT54CFILM IRF7831 www mouser com 942 4 1 87 7 48 Y N MOSFET TRF7831TRPBF Section Total 10 34 Charge Regulator Part Manufacturer Manf Part Quantity Unit Total Ordered Received Price Price 2N3906 www jameco
20. The design of the turning mechanism is critical to the success of the generator system in order to capture the largest amount of energy while maintaining the portability of the overall design There are very few portable hydroelectric generators on the market One of the few available microhydro designs the Aquair UW is a submersible propeller design that can be mounted to a floating platform or a moving water vessel This design type introduces many difficulties one of the most significant being the importance of watertight sealing This is difficult and expensive to construct particularly when there is a rotating shaft involved This design is not realistic considering the time and budget constraints on the project AquaJolt instead uses a floating undershot waterwheel as the turning mechanism Waterwheels have historically been prominent in capturing the energy of a flowing body of water for electrical or other power output However waterwheels have rarely been used in a portable hydroelectric generator application One of the most efficient undershot water wheel designs is the Poncelet design shown in Figure 4 FIGURE 4 PONCELET WHEEL DESIGN Traditional undershot waterwheels which have flat blades extruding radially from a central rotating shaft and fixed to a rim of a wheel are very ineffective at capturing the energy of flowing water typically having efficiencies around 3096 When water flows past the flat blades of this design muc
21. Voltage V FIGURE 52 VOLTAGE MONITOR BEHAVIOR WITH DESCENDING VOLTAGE 52 AquaJolt As in the input voltage decreases the output stays low until it reaches 12 1V Once it reaches this cutoff the output voltage starts following the input voltage linearly This test indicates that once the battery starts to lose capacity the voltage monitor with output a high signal to the charge regulator therefore allowing power to be applied to the battery CHARGE REGULATOR This sections controls whether power is applied to the battery or not The output of the MAX8212 from the voltage monitor section is used here to control a transistor that is used as a switch to allow power to flow through Figure 53 FIGURE 53 CHARGE REGULATOR The 14V power source is used to simulate the output from the buck boost regulator The 12V power source was used to simulate the output from the voltage monitor The multimeter measures the output voltage which is what is applied to the battery The output voltage was measured for various voltage levels from voltage monitor Figure 54 53 AquaJolt Charge Regulator Outputs 5 E 5 gt 5 Input Voltage V FIGURE 54 CHARGE REGULATOR MULTISIM TEST RESULTS This test confirms that the when the charge regulator receives a low signal from the voltage monitor voltage is not supplied to the battery When the charge regulator receives a high signal voltage
22. a FER Xn AE SER Anu iA dS l AquaJolt Requirements Specification OVERVIEW In todayG world electricity is a vital resource that is utilized in almost every nation Electricity powers devices that many people cannot seem to live without such as computers cell phones lights refrigerators and countless other products that define life in the twenty first century Electrical power generation has historically depended heavily on the consumption of fossil fuels However this dependence on fossil fuels has created a false carrying capacity for the globe allowing humans to enjoy a higher standard of living than the earth can sustainably provide Fossil fuels are a limited resource and we consume them at a faster rate than the world can produce them As fossil fuels continue to increase in price and decrease in availability sources of alternate energy are becoming critical for supplying all our energy needs Humanity has tried to harness the sun the wind even the movement of the tides in order to capitalize on natureG perpetual sources of energy These alternative energy generation methods are based on renewable energy sources and have significantly less negative environmental impact than fossil fuels One common form of energy that has been harnessed since the Hellenistic period is the force of a flowing body of water Unlike solar or wind generation methods which depend heavily on ideal weather conditions hydroelectric generation depends
23. ation is critical for the user to know so that they can know if there is enough capacity left on the battery to operate the device properly 40 AquaJolt Battery Status gt g en gt 2o 4096 6096 8096 10096 State of Charge FIGURE 36 LEAD BATTERY STATUS AS A FUNCTION OF VOLTAGE http www windsun com Batteries Battery FAQ htm Battery 20Voltages DC TO DC STEP DOWN This section takes the power that is generated by the alternator and smooths out the voltage so that it is at a constant level as well as converts it to an appropriate level to charge the battery and to power the inverter The voltage level will be 14 V This is safe for both the battery and the inverter Two buck boost controllers where considered for this application They are the LM5118 Wide Voltage Range Buck Boost Controller from National Instruments and the LTC3789 High Efficiency Synchronous 4 Switch Buck Boost Controller Using external components they both could be set up to provide 14V The LM5118 was appealing because it allowed an input voltage range of 5V to 78V while LTC37896 input range was 4V to 38V However the LM5118 could only output current at a maximum of 3A while the LTC3789 could output current 5A It was decided to use the LTC3789 because it would meet the power requirement set forth in the technical specifications The minimum required is 50W The LTC3789 can output 70W 14V 5A while the LM5118 can on
24. be very large Even 50 watts would be enough to power the small devices that are common in such areas Aquajolt will consist of a turbine attached to a floating platform and anchored in a moving body of water The turbine will convert the kinetic energy of the water into rotational energy which is translated through a gear System to a generator The generator then supplies power to an on shore charging station via a waterproof cable The device can be disassembled into at most four parts with each part weighing no more than 25 kg a55 lbs in order for it to retain its portability The on shore station will contain a battery that is charged by the generator The battery will be protected from overcharging through a charge regulation circuit An indicator will display the remaining potential of the battery The station is also equipped with an inverter to convert the DC output of the battery to 120VAC which will then be connected to an outlet Another indicator will show whether there is sufficient power being supplied from the battery to the inverter so that the inverter can function http www iea org weo electricity asp AquaJolt FUNCTIONAL DECOMPOSITION OF BLOCKS The following diagrams detail the overall block diagram of the system The numbers found are based off of water flow rates from 0 5 m s The output of the generator was estimated using the experimentally determined values outlined in the fBack EMFosection of this report The wa
25. cally such that there is a constant blade contact area in the water at all times The spacing between vanes was designed such that there is no interference between blades The modified blade design for AquaJolt is shown in Figure 5 below Side View Front View 75 6 R 35 3 cm 36 5 cm Arc Length 49 9 cm FIGURE 5 MODIFIED WATER WHEEL DESIGN One of the most important modifications in the vane design is the width The vane is designed so that when fully submerged the blade occupies a 0 28 m cross sectional area This was determined to be the largest area that would fit through a standard doorway and still provide useful power The 75 cm 30 in width of the vane fits the requirement that the device fits through a standard doorway typically 86 cm wide This blade width requires our housing and wheel supports to be thin or detachable for portability purposes The fact that the blades include a curve into their design made choosing their material a complicated matter One material suggested for the blades was Plexiglas This material could be formed to the proper radius by heating the plastic with a heat gun then pressing the sheet into a 15 AquaJolt wooden mold with the proper radius of curvature This design was abandoned due to both the difficulty in manufacturing a circular wooden mold and the expense of the Plexiglas itself as ten blades would cost over 300 The material eventually chosen was galvanized shee
26. ce is based off of the worst case scenario of the weight specifications listed above For our flotation mechanism and blade length we anticipate a need for a river depth of at least 0 6 m Waterproof Housing This keeps the sensitive electrical components of the generator safe from the spray of the river The housing is made of plexiglass sealed with epoxy to ensure a watertight seal Debris Guard This device serves to keep any wildlife or floating material in the water from hampering the movement of the wheel It will consist of a simple wire mesh that protects the wheel from oncoming debris Waterproof Electrical Housing This section houses all of the electrical components of the system circuits battery and inverter It has a user interface that contains the LED outputs of the battery status indicator and the power status indicators as well as a switch that the user can flip to select where the inverter is powered from It also has a standard AC outlet so that a device can be plugged into it The housing will protect the components from the elements and also keep them safe during normal use and transport The section will be placed on the shore Turning Mechanism This part of the device will be placed in a moving body of water and will function by converting the kinetic energy of the water into mechanical energy The rpm and torques are calculated using a wheel diameter of 1 m and a cross 1 sectional paddle area of 0 28 m and includes a
27. co com www jameco com www jameco com www jameco com www jameco com www jameco com www jameco com www jameco com Inverter Manf Part 239169 1 12562 1 771 1N4743A 3 T R 833 1N4753A 2 T P RFP50NO6 2 1 691180 5 691201 1 690865 3 691260 1 690988 2 690961 1 690620 2 690865 1 691171 1 609043 1 330431 1 30496 1 36038 5 Section Total 5 19 Quantity Unit Price 1 25 0 39 0 08 0 12 1 03 0 03 0 03 0 03 0 03 0 03 0 03 0 03 0 03 0 03 0 09 0 06 0 1 0 05 Total Price 1 25 0 39 0 24 0 24 2 06 0 15 0 03 0 09 0 03 0 06 0 03 0 06 0 03 0 03 0 09 0 06 0 1 0 25 Ordered Received In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab In Lab 66 AquaJolt Item Vane to plywood fasteners Male hose adapter Main Drive Shaft 60 tooth sprocket 18 tooth sprocket 17 tooth sprocket ANSI 25 chain WindBlue Generator Main Shaft Bearings Intermediate shaft bearings Intermediate shaft Inner Tubes Anchor Rope Eyebolts Wire Screen Water Hose Anchors Latch acrylic Sheet Metal battery PCB Board Epoxy Plywod Washers Tax at Lowes Total Cost Price 6 47 0 86 34 87 15 73 5 27 5 07 3 73 0 00 12 31 11 31 6 59 10 00 6 16 4 00 9 47 15 98 15 98 4 47 1 97 50 00 42 00 51 00 5 20 23 72 0 10
28. com 178618 1 0 06 0 06 Y In Lab Trans 7404 www digikey com SN7404NE4 ND 1 0 87 0 87 Y In Lab Inverter 61 AquaJolt Voltage Monitor Part Manufacturer Manf Part Quantity Unit Total Price Ordered Received Price 1 Res www jameco com 690865 1 0 03 0 03 Y In Lab 20 Res www jameco com 691171 2 0 03 0 06 Y In Lab 470kQ www jameco com 691500 1 0 03 0 03 Y In Lab Res 62 AquaJolt Electrical Housing Part Manufacturer Manf Part Quantity Unit Total Ordered Received Price Price 3 Pos www mcmaster com 7343K731 1 5 3 5 3 Y N Swtich Outlet Lowe s 1 3 51 3 51 Y Y Cover Wire Lowe s 15ft 10 73 10 73 Y Y Section Total 244 81 Voltage Monitors Part Manufacturer Manf Part Quantity Unit Total Price Ordered Received Price 4 7KQ www jameco com 691024 2 0 03 0 06 Y In Lab Res 2000 www jameco com 690700 2 0 03 0 06 Y In Lab Res 2kQ Res www jameco com 690937 2 0 03 0 06 Y In Lab 63 AquaJolt Red LED Green LED Part MAX6459 LM1804 5V Reg 7404 Inverter 1150 Res 5 36 Res 2000 Res 40 Res 910 Res 200 Res 1000 Res 1050 Res 5 11 Res 7000 Res 41 20 Res www jameco com www jameco com Manufacturer www maxim ic com www national co m www digikey com www digikey com www digikey com www jameco com www digikey com www digikey com www digikey com www jameco com www digikey com www digikey com
29. d were able to do physical testing Figure 50 LIP omm m mmo D 1 4 4 4 FIGURE 50 VOLTAGE MONITOR TEST When the circuit was constructed based upon the above calculations the cutoff voltage was 13 5V not at 12 5V as specified The values of the resistors were changed and tested until a 12 5V cutoff was achieved The values of the resistors used to achieve this were R1 50kY R2 490kY and R3 20KY The voltage monitor was then tested to confirm its function First the output voltage was measured as the input voltage was increased to simulate a charging battery Figure 51 51 AquaJolt Voltage Monitor Testing Rising Voltage 14 12 E 9 bp 8 gt Input Voltage V FIGURE 51 VOLTAGE MONITOR BEHAVIOR WITH RISING VOLTAGE As the input voltage increases so does the output voltage until it reaches 12 5V Once it reaches this cutoff the output voltage is in the order of mV This test indicates that once the battery is completely charged the voltage monitor will send a low signal to the charge regulator therefore stopping power from being applied to the battery In the second test the output voltage was measured as the input voltage was decreased starting at 15V and going OV This was to simulate a discharging battery Figure 52 Voltage Monitor Test Descending Voltage 5 HB Output Voltage V 15 1O 5 o Input
30. ded The difference will then be calculated and converted to a mass The assembly amp dimensions will also be measured with a tape measure and compared to the dimensions of a standard door frame This test will ensure that the generator retains its portability 2 The generator should be able to produce an average of 50 watts over a six hour period given a flow rate of at least 0 5 m s 3 The assembly should be able to be built in less than one hour by an individual after reading the user manual This test will be performed by four users and the mean time of the installation will be calculated A mean time of less than one hour will be considered a success 4 The generator will be loaded into a pickup truck and transported at least 15 km on dirt roads If it still functions properly then it passes the test of durability IMPLEMENTATION CONSIDERATIONS The apparatus surrounding the generator must be built out of affordable materials that are readily available The target market of this device is for people in very remote areas with limited resources to expensive manufacturing processes Lightweight materials such as wood aluminum and plastics are all plausible options for constructing the device The generator itself must be purchased separately It is not constructed by the product developers of this device The construction should not require highly advanced manufacturing skills in order to assemble AquaJolt oystem Design BACKGROU
31. e overall usefulness of the device The anchor was chosen to be a Fluke style anchor pictured in Figure 15 FIGURE 16 THE PROCESS BY WHICH THE FLUKE ANCHORING SYSTEM RESISTS MOTION WITH MINIMAL EFFORT FIGURE 15 STOCKLESS FLUKE ANCHOR These anchors function by digging into the riverbed at an angle providing a high degree of direct flow resistance This process is shown in Figure 16 Though the anchors are difficult for the flow to dislodge they are easily removed by the user simply by pulling straight up on the cable The stockless Fluke anchor is widely used in sand or mud situations the same types commonly found in rivers The anchors selected weigh 4 kg or around nine pounds each In order to ensure that the Fluke anchors would resist the flow a worst case analysis was performed using the maximum rated river flow rate expected The drag force on a bogy floating in water can be found via the following equation In this formula is the wetted area is the coefficient of friction for the body in question This value is usually found via approximations that treat the object as a flat plate smooth 24 AquaJolt cylinder and so on Since no such formula exists for circular tubes the body was approximated as a smooth cylinder Doing so while unrealistic is as close as the approximations get to reality as the inner tubes are cylinders of a sort The reason that irregular geometries were not used in this consideration
32. ed to the pulley A piece of reflective tape was attached to the shaft of the generator so that the rpm sensor could read the speed of the shaft under whatever torque was being applied The principle behind this test was that when the back EMF of the generator physically appearing as a torque matched the torque that was being supplied by the product of the weight and the moment arm of the pulley the overall rom would be constant So this test provided an idea of how much torque would be needed at particular rpm Two different iterations of this test were performed one with the generator being unloaded and one with the pictured Duralast Gold battery attached While this battery is most likely not the one that will be chosen for the final design it is a lead acid and as such will imitate some of the characteristics of our final choice Figure 27 and Figure 28 show the results of these tests 32 AquaJolt RPM vs Torque Unloaded 0 2 0 3 Torque N m FIGURE 27 UNLOADED ALTERNATOR RESPONSE RPM vs Torque Loaded Torque Input N m FIGURE 28 LOADED ALTERNATOR OUTPUT 33 AquaJolt The next test involved using a machine lathe to turn the generator at a specific RPM then using a Fluke clamp meter as seen in Figure 29 to measure the current produced This meter finds current via induction thus avoiding the possible changes in the circuit that can be introduced when using an inline meter By turning the s
33. eel design However issues were encountered during the wheel design phase that slowed progress on other subsystems such as the housing design The waterproof electrical housing was just recently completed because the components to be housed in it have just recently been selected 68 AquaJolt Work Breakdown Structure Spring 2012 ID 1 1 1 2 1 21 1 22 1 23 1 24 1 25 Task Name Parts Assembly Testing Mechanical Systems Gear and Shaft Turbine Assembly Housing Electrical Systems Charge Regulator Power Inverter User Interface Battery Testing Encasement Final Design Stage gate Description The parts for all subsystems are assembled and tested The mechanical subsystems are constructed The gear and shaft is constructed and the ratio tested The turbine is tested in various flow rates The waterproof chamber for the generator is constructed All electrical subsystems are constructed and tested The charge regulator is completed and tested The power inverter is completed and tested The user interface is completed and tested The battery is installed and tested The waterproof on shore charging station is constructed Teacher evaluation Deliverables An initial model to troubleshoot Working subsystems that meet specifications Results interpretations Results interpretations Working component that meets specifications Worki
34. eft in percentage form The discharge profile of a lead acid battery is fairly linear This system measures the voltage on the battery and through a system of voltage monitoring ICG the percentage is displayed through various LEDG The MAX6459 Voltage Monitor is used to accomplish this Appendix B MAX6458 6459 Datasheet The MAX6459 is comprised of two comparators one for under and one for over voltage detection as seen in Figure 43 A Multisim equivalent circuit shown in Figure 46 was created for this IC because there was not a standard SPICE model for it in Multisim Uv UNDERVOLTAGE OV QVERVOLTAGE FIGURE 45 MAX6459 FUNCTIONAL DIAGRAM 47 AquaJolt FIGURE 46 MAX6459 MULTISIM EQUIVALENT CIRCUIT Five of these ICG can be set up along with a few other external components to measure the voltage of the battery and display its state in 10 different increments The circuit diagram is shown below in Figure 47 10Percent xa 30Percent x 50Percent x ercent USA Fx 7404N 70Percent gt 80Percent 90Percent 5 00kQ en A 4 ERE c 7404N FIGURE 47 BATTERY STATUS INDICATOR 48 AquaJolt The values for the resistors were calculated using the same technique as demonstrated in the Power Status Indicator section The values are shown in the tables below VOLTAGE MONITOR The voltage monito
35. el to the generator The formulas behind torque and transmitted rpm for these chain and sprocket pairs are the same as those that govern the relationship between directly mated spur gears The ratio between gear sets is governed by the number of teeth from the driving gear to the pinion The intermediate shaft and sprockets are shown in Figure 21 FIGURE 21 THE INTERMEDIATE SHAFT AND SPROCKETS 28 AquaJolt Figure 22 shows the full gearing system from wheel to generator along with the planned supports for the intermediate bearings These bearings will be double sealed in order to ensure the continued functioning of the device by keeping out any dirt or debris introduced by the system FIGURE 22 THE COMPLETE GEARING SYSTEM DEBRIS GUARD In order to ensure the wheel remains free of floating detritus a debris guard was added to the front to keep the wheel from jamming during use The screen consists of a simple 150X280piece of hardware metal cloth with a size This size will keep most coarse materials from entering the wheel while not restricting the overall flow of water This simple addition helps protect both the device and wildlife from potential harm The screen is supported using short lengths of board This subsystem is shown in Figure 23 FIGURE 23 THE DEBRIS GUARD 29 AquaJolt GENERATOR SELECTION The first piece of electronic equipment to be selected was the generator The two front runner
36. endix Sprockets Datasheet
37. esign criterion using an assumed factor of safety of 1 5 The final length of the shaft was determined to be 0 813 m 329 so that the wheel will still be able to fit through a standard doorframe as part of the project amp requirement specifications The plywood rims of the wheel are connected to the shaft by a three inch aluminum hub This part will be machined out of aluminum bar stock The hub is secured to the rim with eight hex bolts and to the shaft with a setscrew It features a 7 mm fillet to disperse the stress concentrations between the radius changes This hub is shown in Figure 9 FIGURE 9 THE WHEEL S ALUMINUM HUB 18 AquaJolt The bearing selection for the main wheel shaft is also very important to the success of the device For a flow rate of five meters per second the blades would experience a force of approximately 3500 N Through static analysis it was determined that the radial loads the bearings must support are 1700 N and 1800 N The majority of the loading experienced by the bearings are a result of the flow of water rather than from the weight of the wheel itself The main shaft bearings selected APPENDIX F fit the diameter shaft and have a rated dynamic radial load capacity of 5782 N 1300 Ib These bearings are predicted to have a life of 8700 hours if operating at the average anticipated flow rate 2 5 m s which is almost a full year of continuous operation The bearings are double sealed to provide the m
38. h of the momentum is reflected off the blade and lost as heat Jean Victor Poncelet recognized 14 AquaJolt this inefficiency issue and designed a water wheel to better capture the kinetic energy of water in low head situations His design allows water to approach the blades flat to their edge instead of directly at the side like in a traditional water wheel The low angle of attack and curvature of the blade allows water to glide up the vane and receives the water without shock With this design Poncelet was able to record efficiencies of 65 72 which is a vast improvement over traditional wheels After the water initially contacts the blades it glides up the vane for the first 15 of rotation demonstrated in Figure 4 transferring much of its momentum into the rotation of the wheel For the next 15 of rotation the water flows back down the curved vane adding more impulse to the rotating wheel and providing more energy Since Aquauolt is designed for zero head situations instead of low head with a controllable water channel the Poncelet design had to be modified to better fit the portable application The AquaJolt water wheel still operates on PonceletG basic principle of curved vanes with minimal shock but the modified wheel has fewer vanes that are much wider The wider vanes allow the device to have more surface area contact with the body of water allowing it to capture more kinetic energy The number of vanes was determined geometri
39. haft at a given RPM measured by the sensor and kept constant by the lathe the output current of the generator could be tested Figure 30 shows the results of this test FIGURE 29 FLUKE CLAMP METER Lathe Generator Test RPM 100 80 60 40 20 pc Current A 15 FIGURE 30 LATHE GENERATOR TEST RESULTS With these two graphs an estimation of the torque needed for a given current can be made allowing the wheel design to be based on generator characteristics These tests will be performed again once the designG actual battery has arrived in order to ensure that the device will still function as expected 34 AquaJolt HOUSINGS AND MOUNTINGS Wheel Support The wheel itself is supported by a wooden A frame This support design helps to distribute the load from the wheel across the support platform The bearings are held onto this support using strips of aluminum that are screwed into the supports This method of attachment allows the wheel to be removed from the platform for easier transport The A frame support is shown in Figure 31 FIGURE 31 THE A FRAME SUPPORT FOR THE MAIN WHEEL 35 AquaJolt Generator The generator will be contained inside a small Plexiglas box This box will be secured to the plywood decking through the use of L brackets and screws The box itself is a 200 mm cube allowing extra room in the back for the generator amp mounting and the wires attached to the generator This box
40. irements but would also give the user a large storage capacity so that his or her appliances can function for an extended period of time Several different types of battery chemistries that met these two requirements were considered Their characteristics are shown below in Table 1 TABLE 1 BATTERY TYPES Criteria Lead Acid NiMH NiCd Voltage V 12 12 12 Current A 10 10 10 Mass kg 3 3 1 63 2 64 Volume cm 1089 5 708 4 1618 4 Cost 29 90 99 95 169 Specs from www batteryspace com 39 AquaJolt A decision matrix shown in Table 2 was created to determine which one of these batteries would best meet our needs both technically and with regards to the budget TABLE 2 BATTERY SELECTION DECISION MATRIX 1 8 9 18 Voltage V 0 2 9 1 8 Current A 0 2 9 1 8 1 8 9 1 8 Mass kg 0 15 1 0 15 1 35 5 0 75 Volume cm 0 15 5 0 75 1 35 1 0 15 Cost 9 1 Based on these results we have decided to go with a lead acid battery Figure 35 While it is marginally larger than the NiMH battery the cost of this battery really makes this appealing for our project since we are greatly constrained by the budget 10 12 12V 10AH 20HR mointencnce treo rechargecble battery FIGURE 35 12V 10AH LEAD ACID BATTERY BATTERYSPACE COM Another advantage of the lead acid battery is that it has a fairly linear discharge profile as demonstrated in Figure 36 This inform
41. itor 0 5 V 0 35 mA OUTPUT DC Power 0 or 0 14 V 0 3 A Voltage Monitor The voltage monitor checks the voltage on the battery to make sure it does not raise above the specified level for the battery 12 V If the voltage on the battery is lower than 12 V it sends a high signal out to the charge regulator allowing power to be supplied to the battery Once the voltage on the battery rises above 12 V the voltage monitor sends out a low signal to the charge regulator to supplying power to the battery INPUT DC Power 0 12 V 0 20 mA OUTPUT DC Power 0 5 V 0 35 mA Battery Status Indicator The charge status indicator will show how much capacity is left on the battery as a percentage by measuring the voltage The voltage range for this application is from 10 5V to 12 75V If the battery gets below this voltage it becomes unusable Therefore 10 5V was selected as 096 of capacity INPUT DC Power 0 12 75 V 0 100 mA OUTPUT Remaining voltage on the battery shown in a percentage through a range of LEDs Switch The switch will allow the user to select if power is sent to the inverter from the battery or straight from the generator or if no power is sent according to the output of the power status indicators INPUT DC Power 0 14 V 0 5 A from Generator 0 12 V 0 10 A from Battery User Selection OUTPUT If in one of the on positions DC Power 0 14 V 0 5 A from Generator 0 12 V 0 10 A from Battery If in the off position
42. le to choose whether the energy will be sent directly through an inverter to the appliance to be charged or if the energy will be stored in a battery to be used at a later time If the user wants to charge an appliance directly the power will be inverted and sent to a standard AC 120 VAC 60Hz outlet where a single appliance may be plugged in The power generation will be monitored to verify the state of the output energy CUSTOMER NEEDS Lightweight Packable and portable Easy to install Low noise level Appears finished Powers multiple appliances No risk to user or environment Low maintenance Durable Po gt Ol P AquaJolt TECHNICAL SPECIFICATIONS o co o Mom 10 Power output for multiple appliances supplies at a minimum 50W at 120VAC to a standard outlet Lightweight Less than 25 kg or can be easily separated into at most four pieces that are less than 25 kg each Portable Fits through all standard doorways 0 81m x 2 1 m Easy to install Capable of being installed within one hour by a single person after reading the user manual Appears finished No dangerously exposed moving parts or wires Durable Able to withstand transport Low noise level Produces less than 100 dB when operating from a distance of two meters Very low maintenance Does not require adjustment or handling in a six hour period No risk to user or environment Electrical components a
43. losses than do traditional directly mated gears mostly due to slack in the chain However their efficiencies are still around 97 so these losses are not necessarily an issue With the chain comes a flexibility of design as the pinion gear can be some distance away from the driving gear limited only by the chain in use The sprockets chosen for the device were machinable bore sprockets due to the fact that the generator shaft is an irregular diameter These sprockets can be bored out to whatever diameter the projects demands allowing greater flexibility in the design process The sprockets themselves are secured onto the shafts using setscrews that are included with the sprockets The ball bearings for the shaft are also double sealed and are mounted the same way as are the wheel shaft amp bearings A ratio of 10 1 was initially chosen in order to simplify the number and type of gears used As a 10 1 ratio cannot be achieved with a single common chain and sprocket pair it became necessary to include an intermediate shaft The diameter of this shaft was found to be 2 23 cm 7 89 using the Distortion Energy Modified Goodman design criterion This shaft requirement limited the kinds of sprockets that could be used as sprockets that would produce the exact gear ratio of 10 1 were found to be either too small or too large to fit on the 7 80shaft The final ratios chosen were 3 33 1 and 3 53 1 leading to an overall ratio of 11 76 1 ratio from the waterwhe
44. ly output 42W 14V 3A 41 AquaJolt VPULLUP Vin 5V TO Cin 4TyF SiR422DP Qc SiR422DP Qp SIR422DP FIGURE 37 12V 5A BUCK BOOST REGULATOR CONFIGURATION Figure 37 shows a typical application of the LTC3789 set for a 12V 5A output It can be configured for a 14V output by using the following equation from page 23 of the datasheet Appendix A LTC3789 Datasheet 1 0 8 Output voltage is 14V Let R1 20kY Then R2 330kY Since no SPICE model was available for MULTISIM use this configuration was then modeled in the LTSPICE IV software available from the manufacturer Figure 38 42 AquaJolt IN 1 1 b 4 7u Vin INTVcc EXTVcc Vinsns Voutsns 30 R6 Pgood losense Tes 4 Iw R7 Run losense v V u D1 100 Boost Boost2 27 hil m Bis Rioad TG4 A TG2 D 185817 10 270p 6 17 IRF7831 sw Q3 FH BG1 B BG2 C LTC3789 Mode PLLIN gt cs R5 il ss AT i er TON 330k 1th FB 4 0 01p SGND Sense Sense PGND 14 7 R3 Cpar 1000p Y e 20k 10m V L4 47 FIGURE 38 14V 5A BUCK BOOST REGULATOR CONFIGURATION The output was simulated using varied input voltage levels to confirm if it would output 14V The outputs for 10V 20V 30V and 40V are shown in Figure 39 Figure 40 Figure 41 and Figure
45. m charging current of 3A but the output from the buck boost controller is 5A The LM350 3 Amp Adjustable Regulator was chosen for this purpose Appendix D LM350 Datasheet It can be configured as a Low Cost 3A Switching Regulator as shown in Figure 57 55 AquaJolt LM150 FIGURE 57 LM350A REGULATOR CONFIGURATION Based on page 5 of the datasheet the resistor values are calculated using the following equation Let R1 5kY R2 42 5kY This connected to the output from the charge regulator so that it limits the current flowing to the battery INVERTER DESIGN DC AC inverter is an electrical device used to produce main voltage AC power from the low voltage DC power so that it can be used by the user Power from 12V 10Ah lead acid battery will be connected to the inverter which will output 120VAC according to the 120V 60Hz transformer 12VDC 10A 120VAC 800 ma FIGURE 58 THE INVERTER CONVERTS DC POWER TO USEFUL AC POWER Due to the high cost of purchasing an inverter AquaJoltG inverter was decided to be built in the lab Since some of the components are available in the Harding Electrical engineering lab they do not need to be purchased This will reduce the expenses in our budget The transformer seen in 56 AquaJolt Figure 59 which is the main component to be used was obtained from an old microwave which is rated at 1000 W power and has a secondary to primary turns ratio of 6 1 r 2
46. ng subsystems that meet specifications Working component that meets specifications Results interpretations Results interpretations Results interpretations Working component that meets specifications Start stop 1 9 3 1 1 9 1 3 1 1 9 i 2 6 1 91 2 22 2771 3 1 1 91 3 1 1 9 2 25 1 9 1 28 1 91 2 22 1 30 2 22 1 30 2 22 3A 1 3 1 Team members ALL ALL J M K ALL 69 AquaJolt 3 System Integration The completed A completed device 3 21 3 30 subsystems are to troubleshoot combined Acceptance Tests The ABET tests are N A 4 191 ALL Complete completed 4 19 Final Report The final report is Document 3 27 1 ALL written 4 24 70 Appendix A LTC3789 Datasheet Selected Pages full datasheet can be found at http cds linear com docs Datasheet 3789fa pdf Appendix B MAX6458 6459 Datasheet Selected Pages full datasheet can be found at http datasheets maxim ic com en ds MAX6457 MAX6460 pdf Appendix C MAX8212 Datasheet Selected Pages full datasheet can be found at http datasheets maxim ic com en ds MAX8211 MAX8212 pdf AquaJolt Appendix D LM350 Datasheet Selected Pages full datasheet can be found at http www national com ds LM LM150 pdf Appendix E Battery Datasheet Appendix F Main Shaft Bearings Datasheet Appendix G Intermediate Shaft Bearings Datasheet Appendix H Shafts Datasheet App
47. nical engineers Taylor Gammon and Joshua Pilgrim and two electrical engineers Mary Samoei and Kendall White Each team member will contribute equally to any efforts of documentation and brainstorming along with being responsible for their individual components of the overall design It is important to note that all members of the team are expected to work with the others to aid them on their own projects as well in order to ensure that each component of the entire design can be successfully integrated at the end of the design process Kendall White Kendall is the project manager and electrical engineer for the AquaJolt project He is responsible for the charge regulator and battery selection Kendall and Mary will work together to design the waterproof on shore charging station Taylor Gammon Taylor is the mechanical engineer working with Joshua concerning the turbine design and the generator housing design He is individually responsible for the gear design Joshua Pilgrim Joshua is the mechanical engineer working with Taylor concerning the turbine design and the generator housing design He is individually responsible for the generator selection Mary Samoei Mary is the electrical engineer responsible for the selection of the inverter and the design of the user interface Kendall and Mary will work together to design the waterproof on shore charging station 13 AquaJolt Mechanical Design TURNING MECHANISM Water Wheel
48. ors at a large angle introduces additional forces onto the rope At 35 the force experienced by each rope increases to 610 N A diagram showing the placement of the anchors can be shown in Figure 18 35 00 River Flow Direction lt 35 00 FIGURE 18 PROPER ANCHOR PLACEMENT WITH REGARD TO THE PLATFORM The eyebolts are placed on the upstream side of the floatation platform as shown in Figure 19 and secured on to the platform through the use of nuts 26 AquaJolt pauc FIGURE 19 THE ANCHORING EYEBOLTS GEARING A gearing system will be implemented in order to maximize the rotational speed of the generator shaft Since the waterwheel design has an inherently low rpm coming in at 19 rpm given a flow rate of 1 m s and a wheel diameter of 1 m a gearing system will be used to increase the rpm at the cost of torque The original design called for simple spur gears This style of gear offers high durability and efficiency along with a compact design to reduce the overall bulk of the system However as gear prices were examined they were deemed too costly to consider for use in the final design They were replaced by a chain and sprocket type system similar to those found on most bicycles An example is shown in Figure 20 FIGURE 20 CHAIN AND SPROCKET TYPE GEARING 27 AquaJolt Chain and sprocket gears while less expensive than their spur gear counterparts possess more inherent
49. ost resistance to damaging effects of moisture due to the operation environment The bearings will be press fit onto the shaft after the wheel has been installed Power and Efficiency The goal of the turning mechanism is to capture as much of the kinetic energy of the moving water as possible and use this energy to turn a generator to produce electrical energy To understand the feasibility of any design it is important to know the maximum power available for a given cross sectional area of a stream The total stream power available for a given cross section of a stream is given by where A is the cross sectional area and V is the stream velocity Given a cross sectional area of 0 28 m the total stream power can be plotted as a function of stream velocity as shown in Figure 10 19 AquaJolt Total Stream Power Total Stream Power System Power 3 Velocity m s FIGURE 10 TOTAL STREAM POWER AND PREDICTED SYSTEM POWER For the system power plot shown in Figure 10 an overall system efficiency of 4096 was assumed For a 40 efficient system a flow rate of 1 0 m s is required in order to produce the specified 50W output FLOTATION MECHANISM The original idea to provide floatation was to use some sort of long metal or plastic pontoon in order to make sure the device stayed straight along the direction of flow However the price of these devices was soon determined to be too great for the budget to
50. r section measures the voltage level the battery is currently at and determines if the battery is charged or not The MAX8212 Voltage Monitor will be used accomplish this One common application of this IC is for overvoltage detection Figure 48 which is what we needed it to do The block diagram is also shown below Figure 49 49 AquaJolt HYST OUT MAXLAA 8211 MAXBZTZ THRESH GND FIGURE 48 MAX8212 OVER VOLTAGE DETECTION CIRCUIT Y HYST OUT FIGURE 49 MAX8212 BLOCK DIAGRAM This section will measure the voltage of the battery and output that voltage until it reaches the preset level 12 5 V Once it goes above this level indicating that the battery is charged it will output a logic low 0 V This output is connected to the charge regulator which controls whether or not power is applied to the battery It will allow power through until it receives a logic low from the voltage monitor Based on page 5 of the MAX8212 Datasheet Appendix C MAX8212 Datasheet the values for the resistors were calculated as follows Choose a value for R1 Typical Values are in the 10 kY to 10 MY range 50 AquaJolt Caluclate R2 _ C 115 Ee EE Calculate R3 _ 21137 3 dE Set R1 50 R2 406 5 R3 89 A SPICE model for this IC was not available in MULTISIM so we could not simulate it in MULTSIM We were able to receive the physical IC in the mail an
51. re water proofed shielded there are no sharp edges exposed does not harm wildlife and contains no toxic materials Functions in most rivers Requires a water velocity of at least 1 m s and a minimum depth of 0 6 m AquaJolt NEEDS METRICS MATRIX uol je e1su pue uoneqiodsueg wuanba 5 gt SI WSIUEYIOIN ruolsiAJadns 1965009 9JinbaJ 100 Soo 5 e214329 a 5 dueys ON JO MOS 1 1 S941M JO syed p sodx punos Jo gp 00T uey ss e npoaud 32npoJd suoies Apjaimun uo 35 10 sajpuey ssassod 941 duluieJ1 jeroads ou sasinbay noy euo Jesn y UOSJEd Jo ajqedey u3e 8367 uey OU sued 5 aq ue Light Packable Easy to install Low noise level Appears finished Powers multiple appliances No risk to user or environment Low maintenance Durable AquaJolt TESTING PLANS 1 The assembly will be weighed using a bathroom scale A person will first be weighed and the weight recorded The person will then hold the assembly and step on the scale The weight will be recor
52. ser may connect devices to the inverter There will also be a connection for the water hose so that the housing and the wires can be connected to the system The water hose serves as the conduit The user interface and the battery status indicator will be placed on top of the housing covered with transparent Plexiglas for ease of view and to protect it from the elements The housing will contain the inverter battery and all the circuit boards 38 AquaJolt Electrical Design The electrical system has two main purposes sending DC power to the battery to charge it and then sending DC power to an inverter to create AC power for the user The user can select whether power comes from the battery or straight from the generator itself The system features a charger regulator to protect the battery from being overcharged as well as monitors that show the state the battery amp capacity and the state of power coming from both the battery and from the generator These indicators will help the user make a decision on where to draw power from Power is then sent through an inverter creating usable AC power to charge and run devices BATTERY The battery in our project provides us with a means of storing the power that we generate According to the technical specifications for our project we need to be able to generate a minimum power output of 50 W Based on this we decided to go with a 12 V 10Ah battery This would not only meet our minimum requ
53. t metal supported by plywood along its sides Sheet metal is relatively lightweight and less expensive than Plexiglas costing only around 60 for ten blades Galvanized steel is the most likely sheet metal to be used in order to construct the prototype due to availability cost and manufacturing abilities The edges of the blades are tabbed as shown in Figure 6 so that the rims may be properly attached through either screws or bolts The sheet metal will be cut rolled and tabbed using equipment available through the Physical Resources Department FIGURE 6 DEPICATION OF ROLLED VANE WITH TABS The vanes are held in position using two solid marine plywood rims This specialized plywood is made for underwater applications The vanes are fastened to the rim using five distributed evenly along both ends of each vane The wheel in its entirety is shown in Figure 7 16 AquaJolt FIGURE 7 THE COMPLETED WHEEL DESIGN A sample blade was fabricated in order to verify the proposed construction methods This blade does not use the full plywood rim but does serve both to illustrate the relationship between the vanes and the rims and to demonstrate the final size and weight of each blade This prototype is shown in Figure 8 AquaJolt FIGURE 8 THE PROTOTYPE BLADE The shaft for the waterwheel was chosen to be 1 91 cm 349 diameter AISI 1566 steel This decision was made using the Distortion Energy Modified Goodman d
54. table hydroelectric generator will allow people with limited resources to power electronic appliances that connect them to the rest of the world in ways that were previously impossible AquaJolt MISSION STATEMENT The goal of this project is to design a hydroelectric generator for small scale applications using information from existing designs for large scale use This small scale generator will provide a constant source of electricity in places or situations where reliable power sources are scarce A portable hydroelectric generator could be used in developing countries in order to supply individuals with a reliable source of electricity Using gasoline powered generators in these settings can be a difficult proposition due to the lack of steady supply lines needed to constantly fuel them This product will also provide energy at a much lower cost than fossil fuel generators The apparatus is intended to be a temporary source of power and the portability of the device allows users to transport it easily from one location to another DELIVERABLES 1 Portable Hydroelectric Generator 2 System Specifications 3 Test Results 4 User Manual 5 Final Report OPERATION The portable hydroelectric generator will be placed in a moving body of water and secured so that it does not float away Once installed the device will convert the kinetic energy of the moving water into usable electrical energy through a generator The user will be ab
55. ter exit flow rates are based on a 40 energy capture rate and the torques are based on a cross sectional area of 0 28 m Water Water Turning Mechanism 0 5m s 0 3 m s Flotation and Waterproof Housing Green Or Red LED Li Generator Control Circuitry Percentage of Battery Voltage Remaining User Selection FIGURE 1 LEVEL 1 FUNCTIONAL SYSTEM BLOCK DIAGRAM AquaJolt Turning Mechanism Debris Guard Water Turbine Water 0 5 m s 0 3 m s Gearing 0 369 RPM Output 0 369 RPM System Shaft to 0 170N m Generator 0 170N m FIGURE 2 TURNING MECHANISM SUBSYSTEM FUNCTIONAL BLOCK DIAGRAM Waterproof Electrical Housing User Selection DC to DC Step Down Switch Charge Regulator Inverter Battery Battery Power Status Indicator Green or Re Voltage Monitor Battery Status Various LEDs Indicator 0 12 75 0 100 mA 10 5 12 75 VDC 100mA FIGURE 3 CONTROL CIRCUITRY FUNCTIONAL BLOCK DIAGRAM 10 AquaJolt Floatation Mechanism The buoyancy system keeps the turning mechanism at the optimum depth in the water allowing the Poncelet blades to enter the water at a very small angle in order to take advantage of the bladeG unique design The buoyancy will be enough to keep at least 100 kg 8220 Ibs afloat To create buoyancy force able to keep that much weight afloat 0 1 m of water must be displaced This value for the weight of the devi
56. the front of the flotation platform so that water can flow uninhibited into the wheel structure 22 AquaJolt 1 85 0 46 FIGURE 14 THE FLOATATION PLATFORM AS SEEN FROM BELOW ANCHORING The anchoring system for the platform was originally planned to be an on shore hammer piton design in which a cable was strung to either river bank and planted in the ground This dual securing method would not only provide an added means for the wheel to stay parallel with the river flow but also ensuring that the device does not simply float downstream when left unattended This design was eventually abandoned because it severely limits the environment in which the device can be utilized The pitons depend heavily on having an adequate river width and shoreline material 23 AquaJolt This design was replaced by a more traditional method of keeping a floating body stationary anchors The plywood platform will have on either side an eyebolt where the anchor ropes can be attached The ropes each 25 feet in length will be attached to heavy anchors to ensure that the device stays in place One advantage of the dual anchors is that it recreates the stabilizing effect of the shore pitons while being less terrain dependent One limitation that this design introduces is that the river must not be overly deep However the depth of most rivers does not exceed 25 feet so this restriction should not greatly influence th
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