1 / 42

BIWT :: Blade Induction Wind Turbine

BIWT :: Blade Induction Wind Turbine. Team 25 (Steven Pitula , Scott Chen, Sangmin No). Presentation Outline. Introduction Features / Benefits System Overview Individual Part Description with Testing Verification Physical Turbine & Power Conversion System Battery Charging System

lucine
Download Presentation

BIWT :: Blade Induction Wind Turbine

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. BIWT :: Blade Induction Wind Turbine Team 25 (Steven Pitula, Scott Chen, Sangmin No)

  2. Presentation Outline • Introduction • Features / Benefits • System Overview • Individual Part Description with Testing Verification • Physical Turbine & Power Conversion System • Battery Charging System • Tachometer & Braking System • Limitations / Improvements • Ethical Consideration • Q&A

  3. Introduction • BIWT provides eco-friend and efficient solution for current wind turbine manufacturer • The main goal of BIWT is to increase total power produced by wind turbines through the use of electromagnetic induction in the bladesand smart controlling system.

  4. Features & Benefits • Features • Generating extra power in terms of electromagnetic induction • Power conversion • Smart Operation monitoring and controlling (rpm, power output, charging) • Benefits • Clean and renewable energy source • Value for money through efficient power generation • May be implementable on current wind turbines

  5. System Overview – Block Diagram

  6. System Overview – Components • Physical Turbine & Power Conversion System • Induction blades, DC generator • Rectifier, Boost Converter • Battery Charging System • Charge controller • 6V/12V lead-acid battery for storage • Tachometer & Braking System • PIC16F877A • Tachometer

  7. The Turbine • Wood • PVC • Aluminum

  8. Induction System Solenoid length = 4 inches Magnet path = 12 inches The solenoids are connected in series and are positioned at the ends of the blades

  9. Solenoid Testing • 3Vpp up to 10 RPM • 3.5 Vpp from 10 to 30 RPM • Magnets do not move • above 30 RPM

  10. Rectifier and Filter The full-wave rectifier is made of 4 schottky diodes and the filter is a 1mF capacitor

  11. Rectifier/Filter Testing Input = 3 Vpp20Hz Output = 1.15 V 40Hz Vdrop = 0.35V Vripple = 4.9%

  12. Boost Converter • 200uH inductor • 1mF capacitor • Schottky Diode • Transistor

  13. 555 Timer

  14. Boost Converter Testing Efficiency: 15%

  15. Efficiency Losses Pac = Pbc * Erec * Eboost Erec = 71% Eboost = 15% Etotal = 10.5%

  16. Induction vs. Generator Power

  17. Battery Charging System - Overview • Store the power output from wind turbine • Charge controller to choose right storage according to power output from the turbine • Charging controller to maximize charging efficiency and protect the battery and circuit • 3 charging methods • Below 13.5V : Charge 6V lead-acid battery • From 13.5V to 15.1V : Charge 12V lead-acid battery • Over 15.1V : Go to dummy load

  18. Battery Charging System – Storage • Battery Selection • 6V lead-acid battery from Power-Series : 7.0Ah • 12V lead-acid battery from Power-Series : 8.0Ah • Required Charging Current Calculation • 6V lead-acid battery : 7.0Ah / 10Hr battery charging time = 0.7 A required : 8.0Ah / 10Hr battery charging time = 0.8 A required

  19. Battery Charging System – 1st Design • 1st Design • Charge 12V lead-acid battery • Use LM 317 voltage regulator • Assume rectified DC Voltage Input to the regulator • Reasons for Design Failure • Lower power output than we expected • Minimum 18V required for LM 317 • Need to modify the circuit for charging 6V battery • Varying DC power output from wind turbine • Potentiometer

  20. Battery Charging System – 1st Design Schematics

  21. Battery Charging System – 2nd Design • 2nd Design • Multiple charging options • Use LTC 1042 monolithic CMOS window comparator • Assume rectified DC Voltage from the DC generator • Reason of Design Failure • Sudden change of turbine motor • Results change in power output • Testing

  22. Battery Charging System – 2nd Design Schematics

  23. Tachometer • Built in contactless tachometer • RPM = revolutions per minute • Design requirements: • 5% margin of error vslaser tachometer reading • LCD display • Controls braking system • Additional features: • Average RPM with user reset

  24. Reference1 Original Schematic

  25. Early Design Approach • RPM = • Reduce variables • Circuit Requirements • Accurate time detection • Accurate revolution detection • Large number division • TTL? • Solution = embedded systems  microcontroller

  26. PIC16F877A • 8 bit , 256 bytes EEPROM peripheral interface controller • MPLAB IDE / CCS compiler • Up to 20 MHz external CLK • Useful functions • CCP (capture and compare) • 3 timers (scalable) • Interrupt friendly

  27. Timer1 • 16 bit register • Time = (# of counts)x(frequency of counts) • Time = 2^16 x increment frequency • setup_timer_1(T1_EXTERNAL | T1_DIV_BY_8); • Timer 1 increment frequency = 500 khz • Overflow • #int_timer1 : of_count = of_count + 1; • Extend timer1 by 16 bits • Total Time = [2^16x (overflow count) + (Timer1 count )] x increment freq • Time for overflow ~ .131 seconds

  28. CCP1 and RPM equations • Capture Timer 1 on interrupt from pin17 • current_ccp = CCP_1; • setup_ccp1(CCP_CAPTURE_RE); // rising edge triggered • Allows us to measure time between interrupts • Sets sensor requirement: 1 low to high transition per revolution • RPM = 1/[(2^16 x overflow count + captured timer1 count)/60] • AVGRPM = (((x*AVGRPM) +RPM)/(x+1)); x = x+1; • User push button  interrupt  reset x • CCP guide *(reference 3)

  29. LCD 16x2 • LCM –SO SO1602D SR/A LUMEX (testing LCD) • HD 44780 controller LCD front panel • Parallel: 4 data inputs / 2 control lines from pic • Modified Flex_LCD driver *(reference 2) • 500 ms delay • Example print format: printf(lcd_putc,"\fRPM: %f\n",RPM); printf(lcd_putc,"AVG: %f\n",AVGRPM);

  30. Braking System • Old braking system: mechanical friction based • Maximum RPM set in code • When tachometer calculates RPM >= Maximum RPM: • Power mosfet IRL 520 is turned on, LED lights up • Generator terminals shorted • RPM decreases, held in brake mode for 3 seconds • RPM is cleared, brake is removed • Recheck RPM • Reapply brake or do nothing

  31. Tachometer Schematic

  32. Tachometer Fabrication and Testing • Modular approach • LCD constant  LCD variable  CCP  Timer1  RPM (fxn generator)  AVG RPM (fxn generator)  sensor  RPM and AVG RPM (sensor) = Final Product • LCD output test variables vs assembly debug • Over 11 code versions / 35 word pages of debugging procedures • Debugging procedure and documentation: • Problem/Symptom? Identify associated variables • Output to LCD + check • Solution? Modify code / recheck

  33. Sensor Design and Testing • Old design: reed relays • New design: optical sensor • TX / RX pair RX high impedance 1.5 M Ω • From testing: no voltage change (reflective tape) point TX directly at RX .04v voltage change • Use 110 lab optical sensor: OPB607a • Measurements 2mm away • Vambient: 4.63v Vblacktape: 4.81v Vreflectivetape: .84 • PIC: detects high / low / high transition without debouncing

  34. Key Breakthroughs Debugging • LCD variable output: simple counter with 2 variables • Symptom: counter would stop or reset, shifting breadboard • Possible causes: loose pin connections, bad hardware, bad code

  35. Additional Breakthrough Debugging • AVG RPM function (with fxn generator) • AVG RPM = # of revolutions / [total elapsed time / 60s] • Symptom: AVG RPM not displaying correct value - display interrupt count (# of revolutions) and time count increments - set fxn generator to 1 hz (frequency of interrupt) - interrupt count fine , timer count is incrementing too slowly - possible cause : total time elapsed counter or algorithm issue - check code  problem: every CCP interrupt resets timer1, total time is innacurate • Solution: AVGRPM = (((x*AVGRPM) +RPM)/(x+1)); x = x+1; • X will be reset by user push button

  36. Testing and Results • Finished RPM detection Circuit (fxn generator input) • RPM = Frequency x 60

  37. Testing and Results • Final product testing:

  38. Braking System Test • Maximum RPM set in code • Demo : 3000 rpm • Test: Max RPM set to 100 • Source drain impedance switch off (20.18 Ω) • Source drain impedance switch on (.17 Ω) • Drive voltage increased till >100 RPM, LCD display 98 RPM • Brake applied for 3 seconds, RPM drop to 31, led on • Brake disengaged and re-engaged when drive voltage held constant

  39. Limitations and improvements • Generator • Coupling System • Solenoid System • Power Conversion • Charging Circuit

  40. References • 1) http://electroschematics.com/451/digital-bike-tachometer/ • 2) http://www.ccsinfo.com/forum/viewtopic.php?t=30964 • 3) http://www.ccsinfo.com/forum/viewtopic.php?t=29963&highlight=ccp

  41. Q&A

  42. THE END Thank You

More Related