Transcript Speech Operated Mobile Platform

Senior Project –ECE – 2008
Power Conversion Control for a Micro-Wind Turbine
Kevin Donovan, Malysa Cheng
Advisors: Prof. Spinelli, Wilk
Abstract
With increasing demand for alternative energies, wind power is emerging as one of the earth’s viable renewable
resources. Though horizontal-axis turbine designs currently dominate the market, vertical-axis wind turbines
(VAWTs) can provide better performance in lower-class winds. Given the low average wind speeds at Union
College, we have designed a hybrid VAWT with a microcontroller-based power conversion system to effectively
charge a battery over a broad range of wind speeds.
Goals
•Safely charge a deep cycle battery
•Maximize system efficiency
•Broaden range of useful wind speeds
•Record wind speed vs. turbine RPM data
System Overview
Alternator
Rectifier
DC-DC
Converter
Hybrid VAWT Design in SolidWorks
Battery
Inverter
Load
Control Algorithm
Measure
Wind
Speed
Measure
Shaft
RPMs
Measure
Battery
Voltage
Calculate
Alternator
Voltage
Alternator Voltage vs. RPMs
Wind
Torque
AC
DC
Storage
AC
Outlet
9v> Valt > 15v
Log Data
Determine Battery
Charge State
25
Voltage (V)
20
Design
Set Duty
Cycle Ratio
15
10
5
0
0
50
100
150
200
250
300
RPMs
•Alternator with rewound stator for higher
voltages at lower rotational speeds
•Buck/boost converter topology allows for output
voltages above and below input
•AGM battery for safety and depth of discharge
•Anemometer and Hall-effect transistor for wind
speed and RPM sensing
•Basic Stamp 2psx controls DC-DC converter
duty cycle and records sensor data
•Parallax PWMPAL coprocessor allows Basic
Stamp to output PWM signal while also running
the control algorithm
Buck/Boost Converter Topology
Future Work
Once the turbine manufacturing is completed, we
will evaluate its performance in different wind
speeds. With this data, the DC-DC converter can be
optimized for the most frequent turbine RPMs.
We will also investigate more efficient MOSFET
driving techniques.