Improved Electrical Properties of Organic Modified Thermoplastic Insulation Material for Direct Current Cable...

Area of Science:

• Materials Science
• Polymer Science
• Electrical Engineering

Background:

• Thermoplastic polypropylene (PP) is a key material for DC cable insulation.
• Enhancing the electrical properties and recyclability of PP insulation is crucial for advanced power systems.
• Deep trap modification is a promising strategy for improving polymer dielectric performance.

Purpose of the Study:

• To investigate the effect of styrene-maleic anhydride copolymer (SMA) on the properties of polypropylene (PP)-based cable insulation materials.
• To evaluate SMA as an organic deep trap modifier for enhancing DC electrical properties.
• To assess the impact of SMA on space charge suppression and electric field distortion resistance in PP insulation.

Main Methods:

• Preparation of PP, PP/SMA, PP/ethylene-octene copolymer (POE), and PP/POE/SMA insulating samples.
• Comprehensive characterization of meso-morphology, crystalline morphology, and molecular structure.
• Testing of DC electrical properties at varying temperatures (30, 50, 70 °C).
• Analysis using thermal stimulated depolarization current (TSDC) and quantum chemical calculations.
• Simulation of space charge distribution using a bipolar carrier transport model for coaxial cables.

Main Results:

• SMA disperses uniformly in PP with minimal impact on PP's crystalline morphology.
• Introduction of SMA improves DC electrical properties in both PP and PP/POE systems.
• SMA creates deep traps within the material, enhancing DC properties.
• SMA significantly suppresses space charge accumulation in PP and PP/POE insulation.
• Materials modified with SMA exhibit excellent electric field distortion resistance.

Conclusions:

• Styrene-maleic anhydride copolymer (SMA) acts as an effective organic deep trap modifier for polypropylene (PP)-based cable insulation.
• SMA incorporation enhances DC electrical properties and space charge suppression in PP and PP/POE systems.
• SMA is a promising additive for developing high-performance, recyclable DC cable insulation materials.