Overload characteristics of paper-polypropylene-paper cable

Technical Report · Sat Sep 01 00:00:00 EDT 1990

OSTI ID:6771599

Ernst, A ^[1]

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1. Underground Systems, Inc., Armonk, NY (USA)

The short-time rating of PPP pipe-type cable may be lower than the equivalent paper cable sized to carry the same normal load. The ratings depend on the relative conductor sizes and the maximum allowable conductor temperatures of the insulation. The insulation thermal resistivity may be a significant parameter for overload times of approximately one hour and should be verified for PPP insulation. The thermal capacitance temperature characteristic of PPP insulation is not known. However, the overload ratings are not very sensitive to this parameter. Overload ratings are given for maximum conductor temperatures from 105 C to 130 C. Use of ratings based on temperatures greater than 105 C would require testing to determine the extent of degradation of the insulation at these higher temperatures. PPP-insulated cable will be thermally stable over a wider range of operating conditions (voltage and current) compared with paper-insulated cable. The short-circuit ratings of PPP- and paper-insulated cable systems and the positive/negative and zero sequence impedances are compared. 21 refs., 22 figs., 5 tabs.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (USA); Underground Systems, Inc., Armonk, NY (USA)
• Sponsoring Organization: EPRI
• OSTI ID: 6771599
• Report Number(s): EPRI-EL-6929
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
ELECTRIC CABLES
DESIGN
ELECTRICAL PROPERTIES
ELECTRICAL FAULTS
ELECTRICAL INSULATION
PAPER
PIPES
POLYPROPYLENE
UNDERGROUND POWER TRANSMISSION
CABLES
CONDUCTOR DEVICES
ELECTRICAL EQUIPMENT
EQUIPMENT
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PHYSICAL PROPERTIES
POLYMERS
POLYOLEFINS
POWER TRANSMISSION
240301* - Power Transmission Lines & Cables- Power Cables- (1990-)