Computer program for determination of earth potentials due to faults or loss of concentric neutral on URD cable. [BACB Code]

Technical Report · Sun May 01 04:00:00 EDT 1977

DOI:https://doi.org/10.2172/7212946· OSTI ID:7212946

Joy, E. B.; Nunnally, H. N.

Extruded solid dielectric cables with bare concentric neutral wires have received wide industry acceptance for underground residential distribution primary construction. The performance of this type of cable has been outstanding since the early 1960's. However, incidences of corrosion of the bare copper concentric neutral wires have caused the utilities to consider methods of mitigating the corrosion process. One viable method to control the corrosion is to apply an appropriate semiconducting or insulating jacket over the neutral wires. However, the effects of the jackets on ''touch and step'' potentials during short-circuits was not known. A research program was undertaken to develop a general computer program to calculate ''touch and step'' potentials, using the Franksville, Wisconsin Test Data as a basis for verifying the program. An additional objective was to compute earth surface potentials resulting from operation with an open neutral. The basic approach to the calculation of ''touch and step'' potentials is to isolate a section of cable of arbitrary length. A distributed parameter model is used to represent this cable section, the surrounding soil and supplemental grounding within the section. An equivalent circuit is employed to represent the remainder of the electrical system. The calculation of the ''touch and step'' potentials involves the solution of sets of simultaneous equations for the isolated section and Kirchoff's equations for the external equivalent circuit.

• Research Organization: Georgia Inst. of Tech., Atlanta (USA). School of Electrical Engineering
• OSTI ID: 7212946
• Report Number(s): EPRI-EL-545
• Country of Publication: United States
• Language: English

Related Subjects

200301* -- Power Transmission & Distribution-- AC Systems
EHV & UHV-- (-1989)
24 POWER TRANSMISSION AND DISTRIBUTION
B CODES
CABLES
CHEMICAL REACTIONS
COMPUTER CALCULATIONS
COMPUTER CODES
CONDUCTOR DEVICES
CORROSION
EARTH CRUST
ELECTRIC CABLES
ELECTRIC POTENTIAL
ELECTRICAL EQUIPMENT
ELECTRICAL FAULTS
EQUIPMENT
NUMERICAL SOLUTION
POWER TRANSMISSION
SOILS
UNDERGROUND POWER TRANSMISSION