Wave Energy Conversion Team: Andrew Cameron Brent MacLean Helen McDonald Steve McDonald Nicholas Smith Supervisors:Dr. Robert Bauer Dr. Larry Hughes Richard Rachals Sponsor:

The Project Objective To design and build a working scaled model of a 100W wave energy converter. Design Requirements Scalability Serviceability Simplicity Mean power output of at least 100W Cost less than $1, Resilient to adverse weather conditions

The Design Dynamic Buoy Stationary Shaft (stator) Linear Generator and Alignment System are housed within the buoy. Removable Top Cap

Presentation Outline Construction of Reciprocating Inducting Point Absorber (RIPA) Shape Testing Design and Testing of Linear Generator Mathematical Model Concluding Remarks

Construction

RIPA - Construction Design Prototype Proof of Concept Main Components Shaft Pod Buoy Shaft Pod Buoy

RIPA - Construction Construction Characteristics Inexpensive Low or non-corrosive materials Non-magnetic materials Simplistic (University Resources) Primary Element Linear Generator: Coils & Magnets

RIPA - Construction Shaft Assembly Linear Generator Stator Support Shaft Upper Support Shaft Linear Generator Stator Lower Support Shaft

RIPA - Construction Linear Generator Stator Stainless Steel Shaft 510 turns of 30 AWG Magnet Wire per coil Epoxy coated

RIPA – Construction Pod Components Magnet Sleeve Assembly Alignment System Alignment Support Ring Yoke Assemblies

RIPA - Construction Pod Assembly Threaded Rods Set Screws

RIPA - Construction Buoy Assembly Buoy Internal Structure Upper Core Lower Core Top Cap Rubber Foam

RIPA - Construction Overall Assembly

Shape Testing

Buoy Shape Considerations Choose shape based on Lowest Damping Ratio Closest Natural Frequency to Desired Range Verify Mathematical Model Justify Assumptions

Drop Test Dropped Shapes from set height Measured Vertical Displacement Characterized natural frequency damping ratio Verified Mathematical Model

Experimental Correlation

Damping Ratio Variation

Natural Frequency Variation

Desired Range

Shape Conclusions Original Testing Results Cylinder Revised Testing Cone Mishap During Manufacturing of Second Shape

Linear Generator

Linear Generator Design Goal produce a linear generator capable of functioning in multiple wave heights accomplished by the use of annular (ring- shaped) magnets and the orientation of the magnets

Linear Generator Testing Part 1 Predicted Value for Magnetic Flux Magnet Flux Rating =1.21Tesla

Linear Generator Testing Part 1 Drop Testing For Determination of Flux Initial drop testing was performed to try to quantify the amount of flux interacting with coils Single magnet dropped at fixed heights for constant velocity 100 turns of copper Attached to oscilloscope to obtain a reading for maximum voltage

Linear Generator Testing Part 1 Actual Value for Magnetic Flux From the drop testing, peak voltage is determined Velocity, length of coil, and number of turns are known and constant Average Magnetic Flux = 0.46T

Matlab Validation

Drop Testing With Pod Same type of testing as with single magnet Only one velocity could be tested Average Magnetic Flux: B=0.51T

Mathematical Model

RIPA In Action

Mathematical Modeling MatLab Simulink Invaluable tool to build a model Fundamental formulas implemented Built up simulator starting with first principles Specialized simulators for specific tests

Model Verification Simulated lab conditions to ensure that the model accurately predicts results Model validated using multiple test situations Step Input simulation to characterize buoy shape dynamics Drop test simulation to characterize magnet interaction

Model Verification Voltage comparison

Extrapolated Results Simulator used to determine requirements to meet project goal of 100W

Extrapolated Results Magnet strength and scale not changed Buoy dimensions changed Electrical characteristics modified Larger amplitude wave input Requires more coils to accommodate longer stroke Longer period waves

Closing Remarks

Extrapolations Wave Input 0.5 m amplitude, 1.5 sec period Device Configuration 16 inch buoy diameter 500 turns per coil with reduced impedance 50 coils 9 sets of magnets Average Output 100W

Cost Material Changes Magnets Fiberglass Inner core Material

Design Requirements Requirements Met Scalability Serviceability Simplicity Mean power output of 100W Requirements Not Met Cost less than $1, Resilient to adverse weather conditions

Thank You Sponsor Mr. Richard Rachals Supervisors Dr. Robert Bauer Dr. Larry Hughes Technicians Angus Macpherson Peter Jones Greg Jollimore Stuart Carr Brian Liekens Outside Resource Dr. Timothy Little Mechanical Engineering Department

QUESTIONS???