Electrical type tests and the electrical part of the extension of prequalification tests were performed on two 127 / 220 (245) kV cable systems manufactured by PRYSMIAN in 2020 and 2021 at LCOE HV Lab.

The cable systems with total length of around 35-40 m included the following elements:

• Two 127 / 220 (245) kV power cables types with XLPE insulation, 2500 mm² copper cross-section and aluminium tube screen.
• Composite outdoor terminations U_m 245 kV with different creepage distance.
• Dry-type joints with sheath interruption U_m 245 kV.
• Two 245 kV GIS plug-in connectors.

The following electrical type tests were performed according to IEC 62067 Standard;

• Bending test witnessed at Prysmian factory.
• Partial discharge test at ambient temperature after the assembly of the accessories.
• 60 heating cycle tests without voltage.
• Partial discharge test, 191 kV 1.5 U_o, at ambient temperature.
• Tan δ measurement,127 kV U_o, at high temperature, 95-100 ºC in the conductor.
• 20 heating cycle voltage tests.
• Partial discharge test, 191 kV 1.5 U_o, at ambient temperature.
• Partial discharge test, 191 kV 1.5 U_o, at high temperature, 95-100 ºC in the conductor.
• Lightning impulse voltage test 1050 kV at high temperature.
• Power frequency voltage test 254 kV, 50 Hz for 15 minutes.
• Examination of the cable system and the accessories.
• Resistivity of the cable semi-conducting screens on a separate sample.

Assembly of 127/220 kV Cable system at LCOE HV Lab

The electrical test sequence was completed, no signs of deterioration on both power cables and the assembled accessories were detected during the final examination.

Electrical type tests performed on the complete cable system according to section 12.4 of IEC 62067 Standard and electrical part of the extension of prequalification tests performed on the complete cable system according to section 13.3.2 of IEC 62067 Standard were passed successfully.

Lightning impulse test on 127/220 kV cable system

More information: Tomás García tgarcia@ffii.es Paula Cid paula.cid@ffii.es