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Charge Accumulation in the Homo-Crosslinked-Polyethylene Bilayer
Wei Zhao1, Huaqiang Li1, Wenpeng Li2
1State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China.
Materials (Basel, Switzerland)
|May 20, 2022
Summary
Charge accumulation in homo-crosslinked-polyethylene (H-XLPE) bilayers, crucial for submarine cable insulation, reduces breakdown strength. This phenomenon is linked to the homo-junction region
Area of Science:
- Materials Science
- Electrical Engineering
- Polymer Science
Background:
- Homo-crosslinked-polyethylene (H-XLPE) bilayers are used in submarine cable factory joint insulation.
- Dielectric properties of H-XLPE are critical for power transmission reliability.
Purpose of the Study:
- Investigate charge accumulation in secondary thermocompression H-XLPE bilayers.
- Understand the impact of charge accumulation on breakdown strength.
Main Methods:
- Pulse electro-acoustic method for charge accumulation analysis.
- X-ray diffraction and thermal analysis for material characterization.
Main Results:
- Charge accumulation was observed in the H-XLPE bilayer.
- A homo-junction region with high crystallinity and fused lamellas was identified.
- Charge accumulation was attributed to fused lamellas and crystal imperfections in the homo-junction, leading to restricted charge transport and deep traps.
Conclusions:
- The homo-junction region significantly influences charge accumulation in H-XLPE bilayers.
- Understanding this region is vital for designing and operating reliable submarine cable factory joint insulation.
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