Influence of Thermal Aging on Space Charge Accumulation and Dissipation of Cross-Linked Polyethylene With Different Cross-Linking Agent Contents

Shuchao Wang,Minghao Chen,Ruijin Liao,Nengcheng Wu,Jian Li,Yong Li,Quan Zhou

doi:10.1109/access.2020.3021798

Shuchao Wang, Minghao Chen + Show 5 more

Open Access

https://doi.org/10.1109/access.2020.3021798

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Abstract

This article presents the influence of thermal aging on space charge accumulation and dissipation of cross-linked polyethylene (XLPE) with different cross-linking agent contents. In this article, dicumyl peroxide (DCP) and low-density polyethylene (LDPE) respectively are used as cross-linking agent and basic experimental material. Additionally, an improved PEA method is used to measure space charge densities during voltage application and removal when thermal aging time respectively is 0, 5, 15, 30 and 80 days due to higher accuracy. And experimental results indicate thermal aging can introduce negative charge traps into pure LDPE and make space charges easier to inject and accumulate in pure LDPE and XLPE, but space charge densities in XLPE increase more rapidly as thermal aging time increases, moreover, thermal aging can simultaneously increase densities of deep and shallow charge traps in pure LDPE and XLPE, etc. And we have also explained the change of space charge accumulation and dissipation of pure LDPE and XLPE after thermal aging from the perspective of micro-structure change of pure LDPE and XLPE through the quantitative analysis of average charge densities. Besides, theoretical model of the average charge decay has also been summed up, and this model can perfectly reflect the dissipation of space charges in pure LDPE and XLPE of different thermal aging time.

Highlights

Cross-linked polyethylene (XLPE) has been widely used as power cable insulation materials [1], [2]
Few scholars have systematically studied the influence of thermal aging on space charge accumulation and dissipation of XLPE with different cross-linking agent contents, this is exactly the focus of this article
Increases as dicumyl peroxide (DCP) content increases, and these values are shown in Figure 5 (f)

Summary

Introduction

Cross-linked polyethylene (XLPE) has been widely used as power cable insulation materials [1], [2]. Compared with traditional oil-paper-insulated cables, XLPE cables have many significant advantages such as high softening point, low thermal deformation, high mechanical strength at high temperature, light weight, acid resistance, alkali resistance, corrosion resistance, almost no cracking and so on [1]–[4]. Owing to these advantages, XLPE cables quickly conquered the power industry as soon as they came out. Few scholars have systematically studied the influence of thermal aging on space charge accumulation and dissipation of XLPE with different cross-linking agent contents, this is exactly the focus of this article

Methods

Results

Conclusion