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TEAM STEADY SUPPLY

ERIC VANDENBURG, SPENCER HOMAN, TREVOR LARSON and NIK URLAUB

Team website: http://seniordesign.engr.uidaho.edu/2010-2011/microgrid/

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Table of contents: Background Problem Definition Uninterruptible Power Supply (UPS) Current Design Design specifications Load information Proposed Design # 1 Constraints Proposed Design # 2 Proposed Design # 3 Ideas Design Tradeoffs Budget Schedule

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Background: Advanced Electric Ship Demonstrator (AESD)

also known as “Sea Jet” 1/4 scale model, Length: 133 feet, Weight:

239,000 lbs, Location: Bayview, Idaho AESD is used for a variety of different tests and

experiments (eg. Acoustic data collection, Hull modification, Motor types)

Propulsion System is powered by 720 12V@40A/Hr Batteries

Auxiliary System is powered by 4 UPS Shore power, Diesel Engine used for charging

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Problem Definition: This is a Feasibility Study with the following

objectives: Replace the Four Uninterrupted Power Supplies

(UPS) Provide Uninterrupted Power Flow to Every Auxiliary

Load. Increase the Duration of Battery Run Time (Increase

Quiet Mode Run time) Decrease Charge Time for Batteries (Decrease Time Between Quiet Mode Runs) Decrease Acoustic Contamination

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What is an uninterruptible power supply (UPS):

PROSUPS provide a Load with power at all timesDuring connection to Shore/Diesel Generator, Load is powered and battery is charging.During Quiet Mode Runs the Battery supplies the Load with power

CONS UPS are not designed to run on the internal batteries for extended timeUPS are not designed to charge quickly UPS are not designed to minimize acoustics (Inverters)

4 UPS = 4 Inverters = Loud

SHORT QUIET MODE RUNS

LONG CHARGE TIME

ACOUSTIC CONTAMINATION

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Current Design:

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Design specifications: Continuous power supply to the loads at all times. Draw power from a common bus. Batteries capable of providing power for more than

45 minutes. Remove the (4) uninterruptible power supplies

(UPS) causing unwanted acoustics

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Design process: Brainstormed/researched DC microgrids Obtained load profiles from NAVSEA Calculated power consumed by the

auxiliary power system Determined the number of batteries

needed. Would it be feasible to run auxiliary

loads off of the propulsion system.

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Load information:With Onboard Data Acquisition System (ODAS) equipment off:• UPS #1 – 6.0A• UPS #2 – 13.9A• UPS #3 – 2.0A• UPS #4 – 3.3AWith ODAS equipment on:• UPS #1 – 17.4A• UPS #2 – 18.5A• UPS #3 – 7.3A• UPS #4 – 3.3AUPS #4 has weak batteries causing ODAS configuration not

to be utilized for this unit.

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Design Schematic# 1

Estimated run time:46.997 minutes

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Design #1 Calculations

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Constraints: Space: Current UPS dimensions 4*(4ft. by 2ft.

by 2ft.). Battery dimensions 24*(12 in. by 6 in. by 4 in.) SPACE not a problem.

Cost: Compare each design (Comparison in tradeoff Table)

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Design Schematic # 2Auxiliary System ties into one battery string of the Propulsion System

Auxiliary load is roughly only 12% of Propulsion load. Propulsion System will be able to support auxiliary system.

Vital Loads have power at all times

Estimated run time:1 Hour 45 minutes

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Design #2 Calculations

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Design Schematic # 3Auxiliary System ties into all 6 battery strings of the Propulsion System

Auxiliary load is roughly only 1% of Propulsion load. Propulsion System will be able to support auxiliary system.

Vital Loads have power at all times

Estimated run time:21.399 Hours

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Design # 3 Calculations

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Options Considered Current Lead-Acid Batteries (12V @

40A/Hr) Lithium-Ion Batteries (36.8V @ 50A/Hr) Fuel cells (not feasible)

• Size needed for storage• cost

Back up battery bank for Design # 2 Types of Inverters, most cost effective and

easy to implement

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Design Tradeoffs

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Project Learning Gained knowledge of DC microgrids A better understanding of one-line

diagrams Basic battery bank design Better team communication Site visit

The operations and uses of the AESD

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Budget: Site Visit (2): $308.80 Poster: $75.00 Total: $383.80

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Schedule: Start of Semester: January 10, 2011 Detailed Design Review: February 15,2011 Snapshot Day: March 8, 2011 Expo: April 29, 2011 Logbooks Due: May 5, 2011 Final Report: May 5, 2011

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Questions: