The fastest-growing energy source in the United States is renewable energy, primarily from hydro, wind, and solar power. Within the group of renewable energies, solar generation is projected to be the fastest-growing source of electricity in the future, increasing from 11% to 48% by 2050 [1]. The US is also one of the largest and fastest-growing wind markets in the world and considerable investments are being made, or plans to be made, inland and offshore wind farms [2]. The expansion of the renewable energy sector requires immense investments in infrastructure, with significant respect given to underground cable systems. As with all underground cable systems, these must operate with very high reliability and maintain a long service life expectancy to ensure the uninterrupted distribution of power.
Very Low Frequency Testing Solutions
Very low frequency (VLF) is an excellent testing solution for the very long cable systems that typically run from wind or solar farms. When comparing power frequency (60 Hz) to VLF (0.01 – 0.1 Hz), there is a 600x to 6000x less power and current requirement when testing at the same test voltage. This allows relatively small, portable, and lightweight instruments to be used in the field for testing of long lengths of cables. Read more: The Basics of VLF Testing
VLF testing solutions can be used during all aspects of the cable lifetime – for installation, acceptance, and maintenance tests. Incorporating diagnostic techniques, such as tan delta and partial discharge (PD), helps to detect and locate potential problems before cable failures occur. Tan delta measurements are a precise and non-destructive method to provide important information on the extent of aging in cable insulation. PD measurements with source localization capability allow direct allocation of PD activity on cable segments, joints, or cable terminations to determine where the exact weak spots are. A failure during service equates to a significant loss in revenue of the wind or solar farm operator and costs associated with repair or replacement of the cable system. Read more: VLF Diagnostic Cable Testing
VLF Withstand Testing:
- Voltages up to 26.1 kVrms and 34 kV DC
- Ideal for testing voltage class cables up to 20 kV
- Ideal for maintenance testing of 25 kV cable systems
- Weighs only 22 kg (48 lbs)
- Voltages up to 44 kVrms and 60 kV DC
- Ideal for testing voltage class cables up to 35 kV
- Ideal for maintenance testing of 46 kV cable systems
- 2 part design for enhanced portability
- Voltages up to 57 kVrms and 80 kV DC
- Ideal for testing voltage class cables up to 46 kV
- Can also be mounted in a van or trailer
VLF Tan Delta Testing:
- Voltages up to 26.1 kVrms
- Integrated tan delta measuring function – no additional hardware required
- Weighs only 22 kg (48 lbs)
- Ideal for testing voltage class cables up to 20 kV
- Ideal for maintenance testing of 25 kV cable systems
- Voltages up to 44 kVrms
- Integrated tan delta measuring function – no additional hardware required
- Most powerful generator with integrated tan delta measuring function
- 2 part design for enhanced portability
- Ideal for testing voltage class cables up to 35 kV
- Ideal for maintenance testing of 46 kV cable systems
VLF Partial Discharge Testing:
- Rated for voltages up to 44 kVrms
- PD source localization and display of PD activity over the cable length
- Complete PD measurement solution together with Frida or Viola
- Complete monitored withstand test solution and simultaneous tan delta/PD measurement compatibility with Frida TD or Viola TD
- Intuitive and modern software interface
- At 40 lbs the lightest and most compact complete PD measuring device on the market
- Rated for voltages up to 57 kVrms
- PD source localization and display of PD activity over the cable length
- Ideal for PD testing together with the PHG 80 Portable
- Ideal for installation in cable test vans
- Intuitive and modern software interface
- The lightest and most compact PD measuring device on the market up to 57 kVrms/ 80 kVpeak