HV bushings

intro
Transformer bushing - cantilever test

EGU – HV Laboratory a.s. has a long term experience in HV bushings testing. We can provide a full range of type testing of HV bushings with Um up to 550 kV.
New tests according to IEC 60137 and IEEE C57.19.00 have been introduced to cover the whole testing range.

Tests objects:

Tests:

  • AC withstand tests up to 1 200 kV
  • Dry lightning impulse voltage testing up to 2 600 kV including chopped impulses
  • Wet switching impulse voltage testing up to 1 600 kV
  • EMC / RIV testing up to 800 kV
  • Partial discharge measurements up to 800 kV. Background noise level below 1 pC (bridge
    measurement)
  • Tg δ and capacitance measurements
  • Pollution testing of bushings acc. to IEC 60570 up to Um = 420 kV

Cantilever Load Withstand Test

  • Bushing rates: up to 550 kV system voltage
  • Top terminal loading (IEC) & condenser side loading (IEEE)
  • High cantilever loading levels

Temperature Rise Test

  • Transformer bushings, wall bushings, oil-oil bushings
  • Bushing rates: up to 550 kV system voltage
  • High current test transformer 10 kA
  • On-line current and temperature monitoring

Tightness Test

  • Testing acc. to IEC 60137, cl. 8.11 & 9.8 – liquid filled bushings
  • Test chamber 5 600 mm x 900 mm
  • Oil pressurized » controlled temperature of 75 °C
  • On-line temperature monitoring and storage

Thermal Stability Test

  • Bushing rates: up to 550 kV system voltage
  • On-line temperature and tan δ monitoring
  • Conductor losses simulation

Standards:

  • IEC 60137
  • IEEE C57.19.00, IEEE C57.19.01