THE ELECTRIC BICYCLE THE ELECTRIC BICYCLE PROJECT INCLUDING AN PROJECT INCLUDING AN

INVESTIGATION OF HUMAN INVESTIGATION OF HUMAN CYCLING PERFORMANCECYCLING PERFORMANCE

S. I. Brand, N. Ertugrul and W.L. SoongUniversity of Adelaide

School of Electrical and Electronic EngineeringAdelaide, Australia

INTRODUCTIONINTRODUCTION BENEFITS OF ELECTRIC BICYCLESBENEFITS OF ELECTRIC BICYCLES

– CLEANCLEAN

– QUIETQUIET

– EFFICIENTEFFICIENT

– ECONOMICALECONOMICAL

– REDUCED TRAFFIC CONGESTIONREDUCED TRAFFIC CONGESTION

DETERMINE HUMAN POWER FROMDETERMINE HUMAN POWER FROM– Stationary Tests and Mobile TestsStationary Tests and Mobile Tests

DESIGN AND BUILD CUSTOM HUBDESIGN AND BUILD CUSTOM HUB INVESTIGATE BATTERY OPTIONSINVESTIGATE BATTERY OPTIONS DEVELOP CONTROL SYSTEMDEVELOP CONTROL SYSTEM

PROJECT SCOPEPROJECT SCOPE

CYCLING POWER DATACYCLING POWER DATA ATHLETE TIME TRIALS (A.I.S.)ATHLETE TIME TRIALS (A.I.S.) STATIONARY DYNAMOMETER TESTSSTATIONARY DYNAMOMETER TESTS MOBILE CYCLING TESTSMOBILE CYCLING TESTS

HOW MUCH POWER?HOW MUCH POWER?

A Horsepower = 746 WattsA Horsepower = 746 Watts

How much is a “Human Power”?How much is a “Human Power”?

BICYCLE DYNAMOMETERBICYCLE DYNAMOMETER

MEASURED PARAMETERSMEASURED PARAMETERS

DYNAMOMETERDYNAMOMETER– WHEEL SPEEDWHEEL SPEED– PEDALLING TORQUEPEDALLING TORQUE– OUTPUT CURRENTOUTPUT CURRENT– OUTPUT VOLTAGEOUTPUT VOLTAGE

MOBILE DATA LOGGING SYSTEMMOBILE DATA LOGGING SYSTEM– WHEEL SPEEDWHEEL SPEED– PEDALLING TORQUEPEDALLING TORQUE– GEAR RATIOGEAR RATIO

DATA LOGGING SYSTEMSDATA LOGGING SYSTEMS

STATIONARY TESTING STATIONARY TESTING – LABVIEW SOFTWARELABVIEW SOFTWARE

– DESKTOP COMPUTERDESKTOP COMPUTER

– DAQ CARDDAQ CARD

MOBILE TESTINGMOBILE TESTING– VISUAL DESIGNER SOFTWAREVISUAL DESIGNER SOFTWARE

– DATA SAMPLING HARDWAREDATA SAMPLING HARDWARE

– LAPTOP COMPUTERLAPTOP COMPUTER

PEAK CYCLIST PEAK CYCLIST POWERPOWER

0

200

400

600

800

1000

1200

0 20 40 60 80

Time (s)

Po

we

r (W

)

TrainedAthlete

AverageCyclist

SUSTAINED SUSTAINED CYCLING POWERCYCLING POWER

MOBILE DATA RESULTSMOBILE DATA RESULTS

MOTORPOWER

HORSE AND HUMAN POWER HORSE AND HUMAN POWER COMPARISONCOMPARISON

BICYCLE POWER REQUIREMENTSBICYCLE POWER REQUIREMENTS 450 WATTS PEAK450 WATTS PEAK 200 WATTS CONTINUOUS200 WATTS CONTINUOUS

BATTERY ENERGY DENSITYBATTERY ENERGY DENSITY

160 WATT-HOURS WILL PROVIDE

–25 MINUTE POWERED RANGE

–50 MINUTE PEDAL ASSIST RANGE

MOTOR DEVELOPMENTMOTOR DEVELOPMENT

WASHING MACHINE MOTOR

MACHINING ALUMINIUM

WOODEN MOCK-UP

FRONT WHEEL

MOTOR EFFICIENCYMOTOR EFFICIENCY

BRUSHLESS MOTOR - DC MOTOR DYNAMOMETER

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 500 1000 1500 2000

Motor Speed (rpm)

Torq

ue (N

m)

DC Motor Losses

DC Motor +AC Motor Losses

CONTROL SYSTEMCONTROL SYSTEM

3-PHASE BRIDGE INVERTER BOARD

MICROCONTROLLER and MICROCONTROLLER and PROGRAMMINGPROGRAMMING

MICROCHIP PIC16F877 MICROCHIP PIC16F877 14 BIT CORE14 BIT CORE 20MHz20MHz 33 INPUT/OUTPUT PINS33 INPUT/OUTPUT PINS 8 ANALOG INPUTS8 ANALOG INPUTS

MICROCHIP RESOURCESMICROCHIP RESOURCES– PIC MICROCONTROLLERSPIC MICROCONTROLLERS

– MPLAB SOFTWAREMPLAB SOFTWARE

– PRODUCT DATA SHEETSPRODUCT DATA SHEETS

– APPLICATION NOTESAPPLICATION NOTES

C – COMPILERC – COMPILER CHIP PROGRAMMERCHIP PROGRAMMER

MOTOR WAVEFORMSMOTOR WAVEFORMS

100% PWM100% PWM 40% PWM 40% PWM

CONCLUSIONS CONCLUSIONS and FUTURE WORKand FUTURE WORK DIRECT DRIVE HUB MOTORDIRECT DRIVE HUB MOTOR

– EFFICIENT (84%) AND LOW MAINTENANCEEFFICIENT (84%) AND LOW MAINTENANCE

BICYCLE POWER REQUIREMENTSBICYCLE POWER REQUIREMENTS– 200 WATT CONTINUOUS, 450 WATT PEAK200 WATT CONTINUOUS, 450 WATT PEAK

BATTERY CAPACITYBATTERY CAPACITY– 160 WATT-HOUR160 WATT-HOUR

USER INTERFACEUSER INTERFACE– LCD DISPLAY and KEYPADLCD DISPLAY and KEYPAD

– INPUT - CUSTOMISED RIDER SETTINGSINPUT - CUSTOMISED RIDER SETTINGS

– OUTPUT - SPEED, DISTANCE AND BATTERY STATEOUTPUT - SPEED, DISTANCE AND BATTERY STATE

CUSTOM BUILT MOTOR CUSTOM BUILT MOTOR – RARE EARTH MAGNET ROTORRARE EARTH MAGNET ROTOR

– INCREASE EFFICIENCYINCREASE EFFICIENCY

– REDUCED WIEGHTREDUCED WIEGHT