1. Fuel Cell Simulator System Martin Ordonez, Masters Candidate Supervisors: Dr. M. Tariq Iqbal Dr. John E. Quaicoe Faculty of Engineering and Applied Science Memorial University of Newfoundland

2. Introduction Fuel Cells (FC) Why FC Simulators?

3. Organization Direct Methanol FC (DMFC) and Electronic Load Description Dynamic Behavior of a DMFC Fast Dynamic Power Converter for FC Simulators Stand Alone FC Simulator A Novel FC Simulator Based on a Small Single FC Conclusions

4. DMFC System Description Cross section of the DMFC Membrane Electrode Assembly Anode and Cathode Plates

5. DMFC System Description Cross section of the DMFCActual DMFC

6. Electronic Load for FC Systems Conceptual Schematic of the electronic load power stage and instrumentation Picture of the Electronic load

7. An Advanced Electronic Load for FC Systems Conceptual Schematic of the electronic load based on Digital Signal Processor (DSP) DSP board top view DSP board bottom view

8. An Advanced Electronic Load for FC Systems The advanced electronic loadPower module expansion

9. DMFC Steady State Characteristic Curve FC Polarization Curve

10. Dynamic Behavior of a DMFC: Current Steps Response to a series of current steps : v-i plot Response to a series of current steps : time domain plot

11. Dynamic Behavior of a DMFC: Power Steps Response to a series of power steps : v-i plot Response to a series of power steps : time domain plot

12. Dynamic Behavior of a DMFC: Resistive Steps Response to a series of resistive steps : v-i plot Response to a series of resistive steps : time domain plot

13. Dynamic Behavior of a DMFC: Current Ripple DC+AC current test for 25Hz and 400Hz: v-i plot DC+AC current test for 25Hz and 400Hz: time domain plot

14. Power extraction as a percentage of the power extraction without ripple Current Ripple Operation: Output Power Reduction

15. Peak Power Availability Peak power extraction from no-load to 400mA : v-i plot Peak power extraction from no-load to 400mA : time domain plot

16. FC Electrical Equivalent Model

17. Summary Advanced electronic load Dynamic behavior of a DMFC Power reduction with current ripple operation Peak power availability Examination of the generic FC dynamic model

18. Fast Dynamic Power Converter for FC Simulators Dynamic response requirements? Fast dynamic response Large signal frequency response: DC+AC current test for 25Hz and 400Hz: v-i plot Unity Gain Negligible phase shift

19. Evaluation of Isolated Converters Flyback Forward Push pull, half and full bridge Following a reference signalInductor and output current

20. Reversible Buck converter Topology Selected for the Power Converter Advantages: Avoid discontinuous conduction mode Fast capacitor discharge (reverse current) Best switch utilization Suitable for switching surface control

21. Control Strategy: A Simple Analogy Which is the fastest way to travel by car? MallUniversity

22. Maximum acceleration Brake!!!! Control Strategy: A Simple Analogy Answer: Time optimal MallUniversity

23. Control Strategy: Time Optimal

24. Control Strategy: Parameter Change

25. Control Strategy: Normalization

26. Control Strategy: Normalized Switching Surface

27. Control Strategy: More Switching Surfaces

28. Control Strategy: Facts About Switching Surfaces Facts: No unique SS can give a universal solution Simple approach to predict the transient response: The closer the better

29. Control Strategy: Inspection of the Ideal Transient

30. Control Strategy: Region of Convergence

31. Control Strategy: Control Law

32. Power Converter Prototype

33. Simulation vs. Experimental Results

34. More Experimental Results Start up and resistive stepsFrequency response

35. Summary Analysis of the dynamic requirements Converter topology selection Control strategy: Selection of a SS Prototype development Experimental result

36. Stand Alone Fuel Cell Simulator Conceptual block diagram of the system Suitable for Laboratory operation No computer No communication cards No licensed software Small low cost system

37. Parameters of the Model 1) 2) 3) 4)

38. FC Model vs. Actual FC

39. DSP-based Implementation Flow diagram of the FC model and power converter controller

40. FC Stack Emulation: 55 Single Cells in Series Response to a series of current steps : v-i plot and time domain plot

41. Summary Empirical model with reduced computational requirements Development of a stand alone FC simulator based on a DSP The most important feature: portability Good match between the FC simulator and experimental results

42. A Novel FC Simulator Based on a Small Single FC Replacing FC model for a small single FC Include membrane drying, catalyst poisoning, aging, etc. Avoid results that depart from reality Use of scale up rules

43. A Novel FC Simulator Based on a Small Single FC Control Area Network (CAN) bus PC based monitoring and analysis Fast dynamic power converter for FC simulators Four modes of operation

44. A Novel FC Simulator Based on a Small Single FC Control Area Network (CAN) bus PC based monitoring and analysis Fast dynamic power converter for FC simulators Three modes of operation

45. A Novel FC Simulator Based on a Small Single FC Control Area Network (CAN) bus PC based monitoring and analysis Fast dynamic power converter for FC simulators Three modes of operation

46. A Novel FC Simulator Based on a Small Single FC Control Area Network (CAN) bus PC based monitoring and analysis Fast dynamic power converter for FC simulators Three modes of operation

47. Operating Principle

48. Experimental Results: Current Ripple Operation 120 Hz current ripple operation: v-i plot and time domain plot Ch1: Power converter output voltage Ch2: Single FC output voltage Ch3: Single FC output current Ch4: Power converter output current

49. Experimental Results: Current Step Response Current step response : v-i plot and time domain plot Ch1: Power converter output voltage Ch2: Single FC output voltage Ch3: Single FC output current Ch4: Power converter output current

50. Concluding Summary Electronic load development Dynamic test of DMFC Power converter design Stand alone FC simulator A novel FC simulator based on a single FC

51. Acknowledgments Dr. T. Iqbal Dr. J. Quaicoe Ms. Moya Crocker Dr. R. Venkatesan Dr. P. Pickup Dr. O. Yepez Dr. M. Koen Alonso Mr. F. Ghioldi Prof. R. Oros

52. Fuel Cell Simulator System Martin Ordonez, Masters Candidate Supervisors: Dr. M. Tariq Iqbal Dr. John E. Quaicoe Faculty of Engineering and Applied Science Memorial University of Newfoundland Questions?