Rocky Mountain Power 2011 Clinic Project Dynamic Line Rating Preliminary Design Review Project Advisor: Dr. Thomas Schmid Clinic Team Members: Skyler Kershner, Benjamin Sondelski, Trevor Nichols, Shayan Barzagari, Zhao Qi

Presentation Overview Project Background Goals Proposed Solution Additional Considerations System Implementation Model Expected Results Budget / Timeline

Project Background Overhead Conductor Sag National Electrical Safety Code specifies minimum clearance As conductor heats, sag increases Environmental, power considerations Dynamic line rating system needed [1] Clearance Levels

[2] Line Sag Illustration Project Goals Develop dynamic line rating system Combine best characteristics of commercially available models Simple design Implement system in a model Validate collected data [2] Line Sag Illustration

Proposed Method: Thermal Imaging Directly measures sag and line temperature Non-contact measurement [4] Configuration [5] Camera View

Proposed Method: Thermal Imaging Provides high contrast images, temperature measurement Image processing tracks lowest point in line [6] Thermal Image

Proposed Method: Thermal Imaging Limitation: Cost Model Price $19,500 FLIR T620 [7] $13,500 FLIR SC325 [8] FLIR E60 $7,500 [9]

Conclusion Need for dynamic line rating Goals Thermal imaging as potential solution Limitations of thermal imaging Other methods needed

Overview Sag – Tension rating and calculation Tension as a solution Tension as a problem Design Problems/Solutions** Conclusion

Tension as a Possible Solution All-Inclusive Measurement line temperature, environment temperature, solar absorption Accuracy Simplicity Low-Power Draw

Sag-Tension Rating and Calculations D – Vertical sag S – Horizontal length of the span W – Unit weight of the conductor Tr – Resultant conductor tension Th – Horizontal component of tension Fig. 1 Parabolic Sag Curve [10]

Tension as a Possible Problem Cost Actual implementation Required line outage for installation Ice and wind loading Length of Conductor Stretching and high temperatures

Design Problems/Solutions Ice loading Wind loading For structures below 60 feet: For structures exceed 60 feet: Resultant ice and wind loading

Conclusion Overview of Tension Tension pros Tension cons Solutions to tension cons

Overview Magnetic Field Sensing Implementation difficulties Build a model - advantages Conclusion

Magnetic Field Sensor [11] Three Axis Magnetic Field Sensor MAGNETOMETER RS232 W/CASE High Accuracy, <0.5% Full Scale 10 to 154 Sample/Sec Low Power consumption Input voltage range 6 to 15 (VDC) [11]

Magnetic Field Measurement Difficulties

Build a Model Test wide range of aspects Control experiment variables and environment Develop realistically implementable solutions Retain a low budget

Conclusion Magnetic Sensing Magnetic Difficulties Advantages of Model

Overview Proposed Solution Math defining model requirements Measuring Temperature Conclusion

Proposed Solution Mock thermal imaging system [12] [13] Build a model scaled down to 1:30 ratio Approximately 600 feet scaled to 20 feet Measure sag in a controlled environment Clinic Lab – Merrill Engineering Building 2350 Develop an effective dynamic line rating system

Math defining model Tension in the line – direct effect of line temperature Temperature – direct effect of amount of line current Amperage – controlled system input

MEASURING TEMPRATURE

MEASURING TEMPRATURE

Conclusion Mock thermal imaging Proposed Solution Characteristics of model Mock thermal imaging IR thermometer IR video camera

Physical Model: Introduction benefits of in-house scale model power supply electrical diagram conductor span expected model performance

Benefits of In-House Scale Model communications controlled environment simple comparison to IEEE 738 no exposure to weather verification of thermal time constant test bed for future clinics

Power Supply need 480V, 3 phase 208V 3 phase is available 2kVA each power supply losses

Model Electrical Diagram National Electrical Code: bonding and grounding conductor sizing overcurrent protection ground detector

Conductor Span 1½″ PVC structure (FORMUFIT connectors) transparent covering (acrylic or polycarbonate) dead-end attachments

Expected Model Performance 20′ span 200lbs tension at 25°C Sparrow ACSR

Physical Model: Conclusion benefits of in-house scale model power supply electrical diagram conductor span expected model performance

Budget Qty Description Cost Total Total: $1566 1 Transformer $0 2 Cable Transformer Pad $20 $40 4 Various lugs, clamps, connectors $80 Circuit breaker $300 3 Locking plug $42 $126 Tension meter $1000 Total: $1566

Timeline

CONCLUSION Measure Sag Build a Model Desirable: Measure Conductor Temperature Due to budget, use Temp Sensor and IR Camera Validate Measurement Measuring Tension Magnetic Sensor

Contact Info / References Rocky Mountain Power Clinic Team University of Utah Electrical and Computer Engineering Department rmpclinic-2011-2012@lists.utah.edu References [1] “Clearance Levels”, Oct. 3, 2011. [Online]. Available: http://www.pge.com/mybusiness/customerservice/otherrequests/treetrimming/faq/orchard/index.shtml. [2] “Line Sag Illustration”, Oct. 3, 2011. [Online]. Available: http://redefinescience.blogspot.com/2011/05/power-lines.html. [3] “Tension Illustration”, Oct. 3, 2011. [Online]. Available: http://www.ehow.com/how_8049821_calculate-transmission-line-tension.html. [4] “Configuration”, Oct. 3, 2011. [Online]. Available: http://www.eng-tips.com/viewthread.cfm?qid=139418&page=274. [5] ”Power Line View”, Oct. 3, 2011. [Online]. Available: http://forcechange.com/2190/proposed-legislation-would-speed-up-permitting-process-for-transmission-lines. [6] “Thermal Image”, Oct. 3, 2011. [Online]. Available: http://www.x20.org/thermal/. [7] “FLIR T620”, Oct. 3, 2011. [Online]. Available: http://www.flir.com/thermography/americas/us/content/?id=18118. [8] “FLIR SC325”, Oct. 3, 2011. [Online]. Available: http://www.flir.com/thermography/americas/us/content/?id=31095. [9] “FLIR E60”, Oct. 3, 2011. [Online]. Available: http://www.flir.com/thermography/americas/us/content/?id=36820. [10] “Sag and Tension”, Sep. 20, 2011. [Online]. Available: http://www.iaei.org/magazine/2004/05/the-effects-of-ruling-span-on-sag-and-tension/ [11] “Smart Digital Magnetometer HMR2300”, Sep. 30, 2011. [Online]. Available: http://www51.honeywell.com/aero/common/documents/myaerospacecatalog- documents/Missiles-Munitions/HMR2300.pdf. [12] “IR Thermo Gun”, Sep. 29, 2011. [Online]. Available: http://chaermai.en.ecplaza.net/2.asp. [13] “IR Security Camera”, Sep. 29, 2011. [Online]. Available: http://www.buy.com/retail/product.asp?sku=224174617&listingid=157870950&&