1 / 37

Outdoors Power Supply

Outdoors Power Supply. Team 2 ECE 445 Senior Design Saad Baig Arturo Guillen. Table of Contents. Introduction Features Design Overview Testing Successes and Challenges Recommendations Potential Improvements Acknowledgments Questions. Introduction. The outdoor power supply

eddy
Télécharger la présentation

Outdoors Power Supply

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. Outdoors Power Supply Team 2 ECE 445 Senior Design SaadBaig Arturo Guillen

  2. Table of Contents • Introduction • Features • Design Overview • Testing • Successes and Challenges • Recommendations • Potential Improvements • Acknowledgments • Questions

  3. Introduction • The outdoor power supply • Purpose • Implementation • Two stages • Power generation • DC-DC conversion

  4. Features • Multiple outputs (12 V, 5V, Universal) • Portable • Runs on conventional fuel • Ease of use

  5. Design Overview • Basic block diagram

  6. Thermoelectric Generation • What is a TEG? • No moving parts • Completely silent • Highly reliable

  7. Initial TEG Housing Structure • Design parameters • 200 psi Compressive Loading • Uniform Load • Insulation

  8. Final Structure • Fan • Water pot heatsink • Compression at the edges • Insulation at the base

  9. Initial Converter Design • Comparison of different topologies • Flyback and Boost have high efficiencies

  10. IV Characteristic of HZ 14

  11. Flyback Advantages • Flyback Topology • Dielectric isolation • Minimal parts required • Easily derive multiple outputs

  12. Flyback Design Issues • Low input voltage from TEG • Very high peak currents on the primary • Challenging inductor design • Availability of materials

  13. Final Converter Design • Boost topology • Main components • Inductor • MOSFET • Diode • Output Capacitor

  14. Two-Stage Boost

  15. Boost Schematic (PCB Design)

  16. Controller • TPS 43000 • Under-voltage lockout at 1.65 V • Hiccup over-current protection • Imax(hu) = .25 / RDS(ON) = 11.36 A • Low power mode

  17. Inductor Calculations • Minimum inductance needed to avoid operating in DCM • 5 V • Lcrit = 1.908 uH • 12 V • Lcrit = 11.27 uH Lcrit = (Rmin / 2) * Tsw(1-D)2*D

  18. Output Filter • Moderate voltage ripple at the output • 5 V • C0 min = 3.6 uF • 12 V • C0 min = 16.8 uF Coutmin = I0max * Dmax / ( fin * vripple )

  19. Feedback Network • Vr = [Rbias/(Rbias+R1)]* Vout • Vout = [1/(1-D)]* Vin FB pin Vr R1 Vout To PWM Comparator Rbias Vref

  20. Testing: TEG • Approximate module Δ T • Verify power output • Verify module integrity • Calculate temperature differences across interfaces

  21. Approximate Module ΔT • Measured temperatures • Th = 2740 C • Tc = 1250 C • Measured open circuit voltage • Voc = 1.93 V ΔT = 1100 C

  22. Verify Power Output P0 = 4.9 Watts

  23. Verifying Module Integrity • Voltage across .3Ω load • VR = 1.427 V • Module current • I = VR / RL = 4.76 A • Internal resistance • Ri = ( VL-Voc )/ I = .126 Ω

  24. Calculating ΔTi • Interface temperature drop • ΔTi = (Th - Tc) – ΔT = 390 C • Values in the range of 300 C to 500 C are acceptable

  25. Testing: Boost Converter • Vds, Vgs, output voltages and ripple voltages • Efficiencies at different loads • Testing in conjunction with the TEG • Line and load regulation

  26. Converter Waveforms 5 V 12 V Drain Voltage Gate Voltage

  27. 5 V Converter Efficiency 𝜼 = 1 – Ploss/Pin

  28. 12 V Converter Efficiency

  29. 5 V TEG/Supply Testing

  30. 12V TEG/Supply Testing

  31. Line And Load Regulation • 5 V • % Load reg = 2.2 (.11 V) • % Line reg = 1.2 (.06 V) • 12 V • % Load reg = 5.0 (.6 V) • % Line reg = 2.2 (.264 V) % Line regulation = [Vout (highest input) – Vout (lowest input)]/ Vout nominal % Load regulation = [Vout (no load) – Vout (max load)]/ Vout nominal

  32. Successes • Both converters worked • Good efficiencies on the converter • TEG was able to provide sufficient power

  33. Challenges • Lead time on parts • Low input voltage controllers uncommon • Time constraints • Magnetics design can be complex

  34. Recommendation • Importance of documentation • Maintain a well organized lab journal • Record ideas, implementation, test data, etc • Explore multiple sources • Verify design equations against different sources • Utilize design tools provided by manufacturer

  35. Potential Improvements • Circuitry for low-power temperature controlled heat sink fan • Better TEG structure • Compression/Thermal expansion • Uniform Load • Smaller and lighter design • Safety

  36. Acknowledgments • Professor Paul S. Carney • Professor Patrick L. Chapman • Professor Philip T. Krein • Paul Rancuret • ECE machine shop • Scott McDonald • David Switzer • Greg Bennett • ECE parts shop • Mark Smart • Power Lab • Andy Friedl • Kevin Colravy • Ben Niemoeller

  37. Q & A QUESTIONS ?

More Related