NAU Collegiate Wind Competition 2016 Tunnel Team B (Electrical Design) Midpoint Report Michael Evans Korey Holaas Scott Muente Jess Robinson Zachary Sabol Brayden Worrell 2015-2016 Project Sponsors: The U.S. Department of Energy (DoE) & National Renewable Energy Laboratory (NREL) Faculty Advisors: Dr. David Willy and Karin Wadsack Instructor: Dr. Sarah Oman DISCLAIMER This report was prepared by students as part of a university course requirement. While considerable effort has been put into the project, it is not the work of licensed engineers and has not undergone the extensive verification that is common in the profession. The information, data, conclusions, and content of this report should not be relied on or utilized without thorough, independent testing and verification. University faculty members may have been associated with this project as advisors, sponsors, or course instructors, but as such they are not responsible for the accuracy of results or conclusions. 1 Table of Contents 1 – Background ........................................................................................................................................... 5 1.1 – Introduction .................................................................................................................................... 5 1.2 – Project Description ......................................................................................................................... 5 1.3 – Previous Competition Turbines...................................................................................................... 5 2 – Requirements ........................................................................................................................................ 5 2.1 – Customer Requirements ................................................................................................................. 5 2.2 – Engineering Requirements ............................................................................................................. 6 2.4 – Testing Procedures (TPs) ............................................................................................................... 7 2.4.1 - Continuous Power .................................................................................................................... 7 2.4.2 - Withstand Wind Speeds ........................................................................................................... 7 2.4.3 - Fit within the Testing Space .................................................................................................... 8 2.4.4 - Assembly and Disassembly ..................................................................................................... 8 2.4.5 - Shutting Down ......................................................................................................................... 8 2.5 – Design Links (DLs) ........................................................................................................................ 8 2.5.1 - Controls.................................................................................................................................... 8 2.5.2 - Load ......................................................................................................................................... 8 2.5.3 - Power Electronics .................................................................................................................... 9 2.5.4 - Software ................................................................................................................................... 9 2.6 – House of Quality (QFD) ................................................................................................................ 9 3 – Existing Designs ................................................................................................................................... 9 3.1 - Full Turbine Designs ...................................................................................................................... 9 3.1.1 - Aleko WGV75 Vertical Wind Turbine Generator ................................................................... 9 3.1.2 - SunForce 400 Watt Wind Generator ..................................................................................... 10 3.1.3 - Xzeres Skystream 3.1 ............................................................................................................ 10 3.2 – Controls ........................................................................................................................................ 10 3.2.1 – Market Research ................................................................................................................... 10 3.2.2 – Benchmark Testing ............................................................................................................... 12 3.3 – Software ....................................................................................................................................... 12 3.3.1 – Market Research ................................................................................................................... 12 3.3.2 – Benchmark Testing ............................................................................................................... 13 3.4 – Power Electronics ........................................................................................................................ 13 3.4.1 – Market Research ................................................................................................................... 14 2 3.4.2 – Benchmark Testing ............................................................................................................... 15 3.5 – Load ............................................................................................................................................. 15 3.5.1 – Market Research ................................................................................................................... 15 3.5.2 – Benchmark Testing ............................................................................................................... 15 4 – Designs Considered ............................................................................................................................. 16 4.1 – Power Electronics Designs ........................................................................................................... 16 4.1.1 – Passive Rectification with Schottky Diodes.......................................................................... 16 4.1.2 – Active Rectification with MOSFETs .................................................................................... 16 4.1.3 - Active Rectification with MOS-controlled Thyristors........................................................... 16 4.1.4 – Buck-Boost Converter ........................................................................................................... 16 4.1.5 - Flyback Converter ................................................................................................................. 17 4.1.6 - SEPIC Converter ................................................................................................................... 17 4.2 – Software Designs ......................................................................................................................... 18 4.2.1 - Tie Push-Button and Loss of Power Together ....................................................................... 18 4.2.2 - Sensing Circuits to Activate Switches ................................................................................... 18 4.2.3 - Using PID controller and PWM to control TSR .................................................................... 18 4.2.4 - Arduino Sleep Library ........................................................................................................... 19 4.3 – Controls Designs .......................................................................................................................... 19 4.3.1 - AC Wye-connected Brake ..................................................................................................... 19 4.3.2 - DC Dynamic Brake ................................................................................................................ 20 4.3.3 - Mechanical Disc Brake -- Hydraulically Controlled ............................................................. 21 4.3.4 - Mechanical Disc Brake -- Pneumatically Controlled ............................................................ 21 4.3.5 - Hysteresis Brake .................................................................................................................... 21 4.3.6 - Webbed Frog Feet Air Brake ................................................................................................. 22 4.4 – Load Designs................................................................................................................................ 22 4.4.1 - Diversion Load ...................................................................................................................... 22 4.4.2 - Smart Material Load .............................................................................................................. 23 4.4.3 - Heat Sink Fan as a Load ........................................................................................................ 23 4.4.4 - Loads Inspired by Nature ......................................................................................................