1 / 42

Micro-Hydro System Utilizing Rain Runoff

Micro-Hydro System Utilizing Rain Runoff. Group # 9 Mark Boktor Jeff Shearer Charmin Patel TA: Tamer Rousan. ECE 445 May 4, 2010. Introduction. Purpose To utilize runoff rain water to generate power for a sump pump in case of a power outage. Features Regulates DC output voltage

klaus
Télécharger la présentation

Micro-Hydro System Utilizing Rain Runoff

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. Micro-Hydro System Utilizing Rain Runoff Group # 9 Mark Boktor Jeff Shearer Charmin Patel TA: Tamer Rousan ECE 445 May 4, 2010

  2. Introduction • Purpose • To utilize runoff rain water to generate power for a sump pump in case of a power outage. • Features • Regulates DC output voltage • Converts DC to AC for electric machine functionality • Outputs up to 250W

  3. Block Diagram • DC Generator: Outputs DC voltage proportional to speed • DC-DC Boost Converter: Boost DC voltage to 170V and • regulates output • Analog Voltage Regulating Circuit: Provides regulated • power for IC chips • DC-AC Converter: Inverter which converts 170VDC to • 120Vrms at 60Hz • Low-pass RC Filter: Makes inverter output more • sinusoidal

  4. Generators • Initially planned on using AC generator • Used two DC generators on a single shaft • Generators connected in series Shaft link

  5. Generator Output

  6. Generator Efficiency vs. Speed - For 9.1Ω load - Importance of gearbox

  7. DC-DC Converter Requirements: • Receive varying voltage from generator • Must be able to adjust duty ratio => use a PIC • Output approximately 120*√2 Vdc for DC-AC inverter The most important equation:

  8. Part Sizing Capacitor sizing Inductor sizing MOSFETs and Diodes - Obey the ratings

  9. Feedback • Reference voltage and scaled output voltage • Reference voltage is 2.5 V • Scaled output is 2.5 V when output of the first stage is 70 V • Compare the two voltages to determine next action

  10. Why 2-stage? • Scaling a lower voltage allows for greater accuracy

  11. Finite Duty Ratio Adjustment • Accuracy limited by microcontroller • Period of control signal determined by: Tosc*4*(TMR2 Prescale)*(PR2+1) • Duty ratio determined by: “value”/PR2

  12. Finite Duty Ratio Adjustment • Want period to be as small as possible • Tosc and TMR2 Prescale basically fixed • PR2 and “value” must be nonnegative integers • For 50 kHz: PR2 = 99

  13. The “Close Enough” Approach • The output will not be stable when the duty ratio is constantly varying • Designate a range of outputs that are acceptable, and do not adjust duty ratio when in that range • Sump pump runs OK if voltage is not perfect • Noise

  14. Results – Efficiency

  15. Results –Output variation with steady input

  16. Results – Output Voltage Variation Peak variation is about 3 V, 1.76%

  17. Results – Sudden Input Variation

  18. Input Variation – Does it matter? • Is 10 V change in 200 ms realistic? • Momentum of turbine • Duty ratio can change in about 10 ms

  19. DC-DC Converter – Final Design

  20. DC-AC Converter • H-Bridge configuration • Input: 170 VDC • Output: 120 VRMS at 60 Hz

  21. Choosing the MOSFETS • N-channel MOSFET • @VGS = 10 V • RDS(on) = 0.39Ω • Drain-Source Voltage: 500V • Drain Current: 14 A

  22. Gate Driver Circuit

  23. Gate Driver Waveform

  24. Pulse Width Modulation (PWM) • Sinusoidal Output (SPWM) • Sine wave at 60 Hz • Sawtooth wave at 50 kHz • Comparator outputs SPWM • UC3825 and TL598

  25. PWM Waveform

  26. Output with PWM

  27. Complications with PWM Output • Resonant filter (LC) • Maximum Duty ratio: 50% • Minimum frequency: 1 kHz

  28. Using PIC • Use PIC to generate two 60Hz opposite square waves • Output will replace PWM and be fed to the gate driver

  29. Advantages of Using PIC • Simplifies circuits • No sine generating chip necessary • No need for -5VDC for sine chip • No high frequency noise from PWM

  30. Results Using PIC PIC output 60Hz square wave Outputvoltage of Inverter Good frequency output

  31. Efficiency of Inverter

  32. Low-pass RC Filter Cutoff frequency: Transfer Function:

  33. LPF

  34. Efficiency of Inverter with LPF

  35. Inverter with LPF

  36. Efficiency with Induction Machine

  37. Battery/Voltage Regulating • 12V Heavy Duty Battery • In series with generator • Provides power to Driver/PIC • Provides necessary high starting current for sump pump

  38. Future Work • Test with water turbine • Integrate DC-DC converter with DC-AC converter • Improve efficiency of DC-AC converter and LPF • Add method to charge battery when sump pump is not operating

  39. Ethical Considerations • To avoid injuring others, their property, reputation, or employment by false or malicious action • To be honest and realistic in stating claims or estimates based on available data

  40. Thank You • Ali Bazzi • Kevin Colravy • Mark Smart • Grainger Power Lab • All ECE 445 TA’s

  41. Questions ??

More Related