1 / 10

Quarter ending 11/31/01 Task 4.3.1.3 - Integrated Control Strategies Stone/Spitler/Elliott

Oklahoma State University Geothermal Smart Bridge. Quarterly Progress Report. Quarter ending 11/31/01 Task 4.3.1.3 - Integrated Control Strategies Stone/Spitler/Elliott. Accomplishments. Alternative controller (SC2) developed for the model bridge Bridge deck wetness sensor developed

sonnagh
Download Presentation

Quarter ending 11/31/01 Task 4.3.1.3 - Integrated Control Strategies Stone/Spitler/Elliott

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Oklahoma State University Geothermal Smart Bridge Quarterly Progress Report Quarter ending 11/31/01 Task 4.3.1.3 - Integrated Control Strategies Stone/Spitler/Elliott

  2. Accomplishments • Alternative controller (SC2) developed for the model bridge • Bridge deck wetness sensor developed • Preliminary communications infra-structure plan for Smart Bridge control systems developed

  3. Issues driving development of alternative controller • The model bridge heating system uses a single heat-pump and is configured for an ON/OFF controller. • The minimum OFF time after the model bridge heat-pump has been engaged is 5 to 20 minutes. This severely limits modulation of heat into the bridge by controlling length of ON cycles. • The existing simulated MPC controller optimizes heating time by manipulating loop temperature into the deck and is not easily modified to control the model bridge. • Typical warm-up time to 0 0C for the bridge deck is 6-12 hours which is approximately best forecast lead time. • The existing MPC controller does not handle the situation where there is no precipitation, the deck is wet, and the deck surface cools below freezing. • A controller that implements ON/OFF action with dead-band has been implemented successfully (Smith et. al.) on the model bridge.

  4. SC2 Concept • Based on icing prevention through: • Bridge deck wetness prediction • Bridge deck wetness sensing • Bridge deck temperature control. • Uses NWS RUC product • Detect threat of a wet bridge surface • Precipitation • Dew events • Up to 12 hours lead-time. • Existing ON/OFF controller for temperature control. • “leaf wetness” type sensors for deck wetness sensing.

  5. SC2 Algorithm • The ON/OFF controller is engaged during the threat of a wet bridge deck surface. • Once the threat of a wet bridge deck surface has passed, the ON/OFF controller is allowed to disengage. • The ON/OFF controller does not disengage until the bridge deck surface is dry. • If the bridge deck surface is wet and the deck temperature falls near freezing, the ON/OFF controller is engaged.

  6. Smartbridge Control System Communications Elements

  7. Smartbridge control system tasks and information flow

  8. Plans for Next Quarter: • SC2 will be implemented on the model bridge and monitored during the following quarter. • Bridge deck wetness sensor will be tested and performance validated. • A strategy will be identified for implementing adaptivity for the Smart Bridge controller.

More Related