SmartBridge Control Group

1
SmartBridge Control Group

• Outline
• Current Functionality
• Working Control System Simulator
• Control System Overview
• Mesonet Weather Station Integration
• Interface to HVACSIM Bridge Model
• Layered Control Concept
• Simulation
• Current Tasks

2
Control System Overview
Objective - No Ice on Bridge!
3
Layered Control Concept

• Multiple Independent Feedforward Controllers
• Parallel operation
• Worst case scenario rules
• Dynamic Layer Configurations
• Cold weather usually moves NW to SE (in OK)
• Additional layers added to catch unusual weather
• Layers configured based on history, current
  conditions

4
Mesonet Weather Station Integration

• Archived Data for 1993-1999
• Ten stations
• 15-minute data

5
Mesonet Weather Sites
6
HVACSIM Model Integration

• Bridge Response Time
• Iterative with HVACSIM model
• Utilizes Mesonet Weather Data
• On/Off Heat Pump Response
• 33.5oF target average bridge deck temperature
• No Ice on Bridge - Conservative Approach

7
Simulation

• Use archived weather data and HVACSIM
• 60 sec. computer time per run
• Controller - 5 sec.
• HVACSIM Model - 15 to 75 sec.
• 60 hrs. computer time per winter
• System evaluation
• Bridge on-time
• Ground loop temperatures

8
Current Tasks

• NWS Weather Station Integration
• Use to validate, enhance Mesonet data
• Radar-based Weather Front Prediction
• Locate front and project path, speed
• Rough estimate of precipitation
• Bridge Model Enhancements
• Variable Flow Rate
• Evaluate Other Bridge Systems
• Virginia / Oregon

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Tunable User Parameters

• Parameters
• Danger Temp
• Minimum desired average bridge deck temp.
• Approach Temp
• Weather station warning temperature
• Warn Time
• Length of time future weather is extrapolated
• Layer Threshold
• of warnings required to start heat pump