CPET 491 Senior Design Phase II. Solar Mini Blinds

Transcription

1 CPET 491 Senior Design Phase II Solar Mini Blinds With DC DC converters and a supercapacitor storage medium By Josh Stetzel Date: April 24, 2017 Project Advisor: Dr. Hadi Alasti Course Instructor: Prof. Paul I Hai Lin 1 Topics of Discussion Problem topic Feasibility Solar Energy Collection and Conversion Electrical Energy Storage Fabrication Requirements Circuit Design Simulation Prototype Testing Demos 2 1

2 Executive Summary Reduce the dependency on fossil fuels Utilize photovoltaic energy and convert to electrical energy Store electrical energy with supercapacitors Deliverable include the prototype, final report, and project presentation Cost was around $200 Took about 130 hours to complete 3 Problem Topic Natural resources are limited Renewable energy is the future (if we want a future) Currently 67% of electrical energy is produce with fossil fuels 4 2

3 Feasibility Solar mini blinds will perform best in winter months Set it and forget it Li ion batteries more suitable Supercapacitor are impractical, but used to gain knowledge 5 Solar Energy Collection and Conversion 6 solar cells per solar panel 8 solar panels attached to mini blinds Output has been as high as 25V at 210mA Output voltage is regulated to 5V±0.5V 6 3

4 Electrical Energy Storage 400F * 6 at 2.7 volt supercapacitors are in series Input voltage is boosted to 17 volts Output voltage is bucked down to 5V Utilized 4 diodes as leveling circuit 7 Fabrication Process Create solar panels from solar cells Mount solar panels Prototype circuitry Build supercapacitor pack Mount and connect circuitry 8 4

5 Solar Cells Silicon Polycrystalline cells were chosen Cheaper than monocrystalline Produce less power and waste to manufacture About 17% efficiency 0.6% efficiency decay per year 0.6V open circuit voltage per cell 200mA short circuit current per cell 9 Storage Element Supercapacitors Expensive, relatively high capacity compared to normal capacitors Low no load leakage current, 0.85mA after 72 hours Can be stored for several days with usable energy Requires leveling circuit for series configuration 10 5

6 Supercapacitor Wiring diagram Pos D1 D5 D9 D2 D6 D10 D3 D4 C1 400F Supercapacitor D7 D8 C2 400F Supercapacitor D11 D12 C3 400F Supercapacitor D13 D14 D15 D16 C4 400F Supercapacitor D17 D18 D19 D20 C5 400F Supercapacitor D21 D22 D23 D24 NEG C6 400F Supercapacitor 11 Requirements Physical Requirements Functional Requirements Operational Requirements Environmental Requirements Performance Requirements 12 6

7 Circuit Design LM2678T simple switcher for buck converter 8 30 volts in, 5 volts out, max 5A LM2585 simple switcher for boost converter 4 40 volts in, max 65 volts out, 3A max output Utilized standard USB connectors for inputs and outputs 13 Boost Converter Circuit Rb2 From Solar Panels V1 5V Cb1 150µF Rb1 2.94kΩ Cb3 470nF Ub lm kΩ Rb3 19.1kΩ Lb1 68µH Db1 1N4447 Cb2 330µF Pos Neg To Supercapacitors 14 7

8 Buck Converter Circuit From Solar Panels V1 25V Cp7 15µF Cp6 15µF Cp2 15µF Cp3 10nF Cp1 0.47µF Up LM2678t Lp1 22µH Dp1 10TQ045 Cp4 180µF To Charge Medium Cp5 180µF VBUS D+ D- GND Jp1 Shell CASE1,CASE2 USB Type A 15 Supercapacitor Pack 16 8

9 Supercapacitor Pack Simulation 17 Prototype Completed on breadboard first Checked for proper voltage Transferred over to protoboard 18 9

10 Protoboard Buck converter 19 Protoboard Buck/Boost Converter 20 10

11 Testing Various tests were performed through a Rheostat Tests were performed outside on the 23 of April, sunny and 68 F Solar panels without regulation circuitry Neg Voltage Current Load resistance Vsc1 Vsc2 Vsc3 Vsc4 Vsc5 Vsc6 Vsc25Vsc26Vsc27Vsc28Vsc29Vsc30 from Rheostat 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 10V 300mA 35Ω Vsc7 Vsc8 Vsc9 Vsc10Vsc11Vsc12 Vsc31Vsc32Vsc33Vsc34Vsc35Vsc36 12V 280mA 41Ω 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 24V 200mA 165Ω Vsc13Vsc14Vsc15Vsc16Vsc17Vsc18 Vsc37Vsc38Vsc39Vsc40Vsc41Vsc42 25V 170mA 193Ω 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 26V 130mA 260Ω Vsc19Vsc20Vsc21Vsc22Vsc23Vsc24 Vsc43Vsc44Vsc45Vsc46Vsc47Vsc48 Pos 26V 100mA 355Ω 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 0.5V 21 Testing Buck converter testing with a current limited power supply Voltage input Current input Voltage output Current output Load resistance 25.4V 110mA 4.6V 240mA 19.7Ω 25.7V 100mA 4.7V 180mA 26.0Ω 25.4V 60mA 4.8V 150mA 32.0Ω 25.2V 40mA 4.8V 110mA 60.6Ω 25.0V 30mA 4.8V 80mA 60.6Ω 25.0V 30mA 4.9V 60mA 80.6Ω 25.3V 20mA 4.9V 40mA 123.8Ω 25.5V 10mA 4.9V 20mA 247.0Ω 22 11

12 Testing Buck converter testing with solar panels Voltage Current Load resistance from Rheostat 4.77V 150mA 30.7Ω 4.81V 110mA 41.9Ω 4.84V 90mA 54.9Ω 4.87V 60mA 80.0Ω 4.89V 40mA 125Ω 4.91V 20mA 242Ω 23 Final Integration Testing 24 12

13 Physical Requirements Requirement Data ID Requirement Requirement (Shall or Should Type statements) 6 Physical The system shall integrate solar cells onto window blinds 7 Physical The system shall have at least one USB interface 8 Physical The system shall incorporate a voltage regulation circuit The system shall store electrical 9 Physical energy in rechargeable batteries Verification Method Verification Planning Date Verified Inspection Inspection Inspection Inspection Verification Report 25 Functional Requirements Requirement Data ID Requirement Requirement (Shall or Should Type statements) The system shall capture 10 Functional solar energy with photovoltaic cells 11 Functional The system shall incorporate a buck/boost converter Verification Method Verification Planning Date Verified Inspection Inspection Verification Report 26 13

14 Operational Requirements Requirement Data ID Requirement Requirement (Shall or Should Type statements) 1 Operational The system shall capture solar energy 2 Operational The system shall convert solar energy into electrical energy The system shall store the 3 Operational captured solar energy as electrical energy 4 Operational The system shall provide a D.C. output to power a user's device 5 Operational The system should supply D.C. power via the USB interface Verification Method Verification Planning Date Verified Inspection Inspection Test Test Demonstration Verification Report 27 Environmental Requirements Requirement Data ID Requirement Requirement (Shall or Should Type statements) 18 Environmen The system shall be tal exposed to direct sunlight 19 Environmen The system shall operate between 60 and 80 degrees tal F Verification Method Verification Planning Date Verified Inspection Test Verification Report 28 14

15 Performance Requirements ID Requirement Type Requirement Data Requirement (Shall or Should statements) Verification Planning Date Verified Verification Method Verificatio n Report 12 Performance The D.C. output shall be 5V ±.5V Demonstration 4/24/ V 13 Performance 14 Performance The D.C. output shall be capable of supplying the battery with at least 200 milliamps of current The fully charged system shall be able to deliver >= 4W Test Test mA max 29 Performance Requirements Requirement Data ID Requirement Requirement (Shall or Should Type statements) The voltage regulator shall not 15 Performance exceed 100 degrees F 16 Performance 17 Performance The current shall be limited to 1.0 amps The batteries should be capable of at least 1000 mah of energy Verification Planning Date Verified Verification Method Test Test Test Verificatio n Report 300mA max 30 15

16 Cost Material/Tool Cost Item Qty Cost Each Total Cost Comments PCB board 3 $ 0.50 $ 1.50 LM2678T 2 $ 5.82 $ LM $ 6.42 $ 6.42 Resistors 4 $ 0.10 $ 0.40 Capacitors 17 $ 1.00 $ Diode 28 $ 0.54 $ Inductor 3 $ 2.00 $ 6.00 Mini blinds 1 $ $ Supercapacitor 6 $ $ Solar cell 50 $ 0.28 $ $ Material Total $ Project Management 32 16

17 Project Management 33 Original Risk Register ID Entry Date Type 1 2-Nov-16 Schedule IF 2 2-Nov-16 Technical IF 3 2-Nov-16 Technical IF 4 2-Nov-16 Technical IF 5 2-Nov-16 Cost IF 6 2-Nov-16 Cost IF 7 2-Nov-16 Schedule IF Risk Description: 'IF statement' The solar cells will take too long to acquire The current from the solar cells is too great If the solar cells are too heavy It the overcharge circuit malfunctions If my components use too much power The battery gets damaged if the overcharge system won't work THEN THEN THEN THEN THEN THEN THEN Consequence of Risk: 'THEN statement' The integration will be delayed Output current would be outside of parameters the mini blinds won't hold the cells, and won't be able to capture sunlight The battery could explode Must replace with better component Battery must be replaced it will need to be redesigned, leading to a schedule delay Status Likelihood (1-5) Severity (1-5) Score Rank* Response Open Low Mitigate Open Low Mitigate Open Low Accept Open Medium Mitigate Open Low Accept Open Medium Mitigate Open Medium Mitigate Description of Response order them asap Add a current regulating circuit Use a watchdog function to keep tabs on charging have a spare battery on hand Model the system before ordering parts 34 17

18 Risk Register Rev Risk Matrix 36 18

19 Conclusion Solar panels would work better on a mobile platform Li ion batteries would be more suitable Learned valuable information about supercapacitors Gained knowledge on solar energy 37 References Buchmann, I. (2017, Feburary 19). Bu 209: How does a Supercapacitor Work. Retrieved from Battery University: Energy, U. D. (2017, Feburary 19). Frequently Asked Question. Retrieved from U.S. Energy Information Administration: M. Ameer Ur Rehman Sheikh, M. S. (2014). Voltage Balancing of Supercapacitors String using Rectifier Diodes: Analytical and Simulation Ap proach. International Journal of Scientific & Engineering Research, Maehium, M. A. (2017, Feburary 19). The Real Lifespan of Solar Panels. Retrieved from energy informative: solar panels/ 38 19

20 Questions/Comments? 39 Demo With Li ion Battery 40 20

21 Demo With Supercapacitor Pack 41 21