The electricity grid must become greener, smarter and more reliable. But what does this energy transition mean for connecting underground medium-voltage cables? And which cable joint technology performs best in a network with decentralized generation? Choosing the right medium voltage cable joint is more important than ever.
Jointing technologies: heat shrink, cold shrink or liquid insulation?
There are several techniques for connecting cables:
- Heat shrink technique: the sleeve is shrunk around the connector with a gas burner.
- Cold shrink technique: the housing shrinks by removing a spiral.
- Liquid connection technique: the cable connection is insulated with liquid silicone.
Impact of sustainability on the cable network
The energy transition is putting more pressure on the existing grid. Sustainably generated energy from solar and wind farms is fed in decentrally, so that electric currents move in opposite directions. This ‘two-way traffic’ and the use of transmission controllers introduces high-frequency harmonics into the network.
Thermal load and partial discharge: a risk for cable joints
Harmonic networks increase the risk of partial discharges (PDs), which can affect XLPE insulation. Traditional shrink sleeves made of plastic are susceptible to this damage. After a breakdown, the material is irreparably damaged, which leads to malfunctions.
Advantages of liquid silicone technology
- Perfect moisture seal: hydrophobic, forms insulating rubber on contact with water
- Excellent dielectric properties: equal to or better than XLPE.
- Easy assembly: fast, easy and flame-free.
- Long service life: resistant to thermal stress and harmonious.
Do you want to know how your cable network can best be protected? Contact our specialists or view the LoviSil® liquid silicone cable joints on our website.
