8/12/2019 Capstone - Ampacity

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DepartmentofElectricalandComputerEngineering

The examples that are shown here are representative ofthe cables that we used to verify our application. Thecalculations that we performed to analyze and compareour results are modeled off of these examples as well.

Project Description:

We are investigating the methodsthat are used throughout theworld to estimate maximumcurrent carrying capacity ofpower cables; The currentstandards have been individuallydeveloped through recognizedstandards associations overrecent years.

Project Proposal:

We have developed a comparisonof modern day methods used forthe optimal sizing of powercables by devising a MATLABapplication. The applicationperforms complex calculations inorder to draw comparisons andsimplify the comparison process.The resulting conclusions that we

have drawn, provide us withexperiential knowledge on thebest fir comparisons of multipleindustry standards.

Capstone Advisor: Robert Bass, Ph. D. Capstone Coordinator: Prof. Mark Faust Team Members: Sadok Houimel , Abdullah Al Salem, David Dang, Ignatius Frederick Susanto, Solomon Cooper

Summary of Results:

The findings of our research are consistent withthe industry practices and it is generallyconveyed through the percent error differencesthat the standards and commonly used methods

of calculation provide a fairly accurate result.

We still maintain our speculation that estimationof underground cables and the current methodsof calculation that are used are not accurateupon the addition of many variables. It isimperative that advanced methods are used inthe estimation of current carrying capacities.

Common Standards:

IEEE Standard 835 IEC 60287 NFPA 70E 2012

Application Description:

The development of the application is based of thework of J.H. Neher and M.H. McGrath in their 1957paper, The Calculation of the Temperature Rise and

Load Capability of Cable Systems. Neher andMcGraths paper simplifies the complex calculationsused for calculating cable ampacity and the developedapplication follows the workflow diagram that ispresented here. It was necessary to makeassumptions in the calculations such as maintaining asteady state and ignoring the cyclical response thatmost systems normally see.

Heat Transfer Diagrams:

Ladder networks and heat flow diagrams arerepresentative of some of the methods that are used inestimation of the current capacity. These estimatesrepresent the thermal impedances of the cables.