Colorado School of Mines - 2003 Future Energy Challenge

							Colorado School of Mines - 2003 Future Energy Challenge
Participants: Saad Al-Muaili, Kristie Dukeminier, Eric Elson, Steve Englebretson, Erek Hutto, Kevin Pera, and Chris Pink Advisors: Dr. Marcelo Simões, Dr. P.K. Sen, Dr. Felix Farret, Professor Doug Sutton, and Jeferson Correa

Department of Engineering, Golden, CO 80401
Sponsors
•Institute of Electrical and Electronics Engineers (IEEE)
Power Electronics Society, Industry Applications Society, Industrial Electronics Society, and Power Engineering Society

THE COMPETITION
Design and build a prototype 10 kW inverter interface system to convert DC power from a solid- oxide fuel cell to 120/240 V AC power for a residential home

Participating Schools
•Colorado School of Mines •Drexel University •Michigan State University •The Ohio State University •Seoul National University of Technology •Texas A&M University •University of Akron •University of Central Florida •University of Missouri -Rolla •University of Wisconsin -Madison •Virginia Polytechnic Institute and State University •West Virginia University

•U. S. Department of Energy •U.S. Department of Defense •National Energy Technology Laboratory (NETL) •Advanced Energy •Grainger Center for Electric Machinery and Electromechanics •and Others

Main Requirements
• • • • • Low Cost ($40/kW) Safety and Reliability Maximize Efficiency Minimize Size and Weight Minimize Cooling Requirements

Competition Emphasis
• Innovation • Excellence In Undergraduate Education • Practicality and Manufacturability

US Electricity Generation 2000
Renewable 2% Nuclear 20% Oil 3% Gas 16% Coal 52% Hydro 7%

Role of the Inverter
• • • • • Inverter Retail Cost ~ $1000/kW Cannot Use Fuel Cells, PV, Wind Directly Alternative Energies Less Economical Goal to Halve Inverter Manufacture Cost Reduce Cost of Alternative/Distributed Energies Battery Backup
Fuel Cell: 29Vdc

Equivalent Resonant Circuit Analysis

DC-AC Inverter
Load: House 120Vac

VS

il(t) vC(0)=-VS
il ( t )  V s  vc  0  L 
 t

+ _

R/N2 vl(t)

e

sin   t 

v l  t   il  t  

R N
2

Proposed Topology and Control System for Primary Switches US Electricity Use 2002
Other 3% Industrial 31% Commercial 30%
Hysteresis Comparator Timing Sequence

Fuel Cell Communications
vo

Renewable Energy Benefits
• Diversified Fuel Supply – Hydrogen, Sun, Wind in addition to Oil, Coal – Increased Long-Term Economic Security • Increased Efficiency Capability – Chemical Conversion in place of Combustion • Environmental Benefits – Greatly Reduce NOx, SOx, CO2, Emissions

Results of Simulation for 5kW Load
Output

Fuel Cell

FC

Transducers to measure Current & Voltage

vref +

Gating Logic

PI
+ _ + _

_

Reference

RS - 232

Microcontroller •A/D Conversion •Power Calculations •Fault Analog

Residential 36%

Output Voltage
Fuel Cell Converter – Battery Charge Controller

Estimated Customer Cost/kWh
$0.10 $0.08 $0.06 $0.04 $0.02 $Co al Nu Fue P Win cle l Ce hotov d ar olta ll ic

Distributed Power Benefits
• Increased System Reliability • Increased Efficiency Capability
─ Decreased Line Losses ─ Potential For Cogeneration

• Benefits to Power Grid
─ Aid Transmission and Distribution Networks

Results of Simulation for 5kW Load

Fuel Cell

Boost Converter

High Voltage DC link Bus
Resonant Inverter

• High Quality “Premium Power” • Power Where/When Grid Is Unavailable

Zoom of Current Through Resonant Circuit

Current After Cycloconverter

Converter/ Battery Charge Controller

96 V Battery

300W 48 VDC Power Supply