Polymer Insulation Applied for HVDC Transmission

Preface
Contents
Contributors
Polymer Insulation for HVDC Cables
DC Insulation Performance of Crosslinked Polyethylene for HVDC Cables
	1 Introduction
	2 DC Cable Used Polyethylene Materials
		2.1 Low Density Polyethylene
		2.2 Crosslinked Polyethylene
		2.3 Morphology of Polyethylene Materials
		2.4 Defects of Polyethylene Materials
	3 DC Electrical Conductivity Characteristics
		3.1 Charge Conduction
		3.2 Electrical Conductivity and Electric Field Distribution
	4 Space Charge Characteristics
		4.1 Charge Generation
		4.2 Charge Transport
	5 DC Electrical Breakdown Characteristics
	6 Conclusion
	References
Surface Ligand Engineering of Polymer Nanodielectrics for HVDC Cables
	1 Introduction
	2 Surface Ligand Engineering of Polymer Nanocomposites
	3 Surface Ligand Engineering for Advanced Cable Insulating Materials
		3.1 Space Charge
		3.2 DC Conductivity
		3.3 Breakdown Strength
		3.4 Electrical Tree Aging
		3.5 Partial Discharge
		3.6 Thermal Conductivity
	4 Conclusions and Outlooks
		4.1 Conclusions
		4.2 Outlooks
	References
Voltage Stabilizer and Its Effects on Polymer’s DC Insulation Performance
	1 Introduction
	2 Categories, Mechanisms and Hot Research Topics of Voltage Stabilizers
		2.1 Categories and Mechanisms of Voltage Stabilizers
		2.2 Hot Research Topics of Voltage Stabilizers
	3 Effects of Voltage Stabilizer on Polymer’s DC Insulation Performance
		3.1 Influences of Voltage Stabilizer and Its Analogues
		3.2 Voltage Stabilizers for HVDC Cable Insulation
	4 Conclusion
	References
Polypropylene Insulation Materials for HVDC Cables
	1 Introduction
	2 Issues of Space Charge in HVDC Cables
		2.1 The Key Issue in HVDC Cables—Space Charge
		2.2 Space Charge Suppression Method
		2.3 Space Charge Suppression Mechanism
		2.4 Effect of Temperature Gradient on Space Charge in HVDC Cables
		2.5 Effect of Crystal Structure on Space Charge in HVDC Cables
	3 Polypropylene and Their Modification
		3.1 Morphology and Crystalline-Phase-Dependent
		3.2 Modification of Polypropylene
	4 Polypropylene Nanocomposites
		4.1 Zero-Dimension (0D) Fillers
		4.2 One-Dimension (1D) Fillers
		4.3 Two-Dimension (2D) Fillers
		4.4 Other Structure Fillers
	5 Conclusion
	References
The Insulating Properties of Polypropylene Blends Modified by ULDPE and Graphene for HVDC Cables
	1 Introduction
	2 The Properties of PP/ULDPE Blends
		2.1 PP/ULDPE Blends
		2.2 Morphology Observation of PP/ULDPE Blends
		2.3 Melting and Crystallization Behavior of PP/ULDPE Blends
		2.4 Mechanical Properties of PP/ULDPE Blends
		2.5 Electrical Properties of PP/ULDPE Blends
	3 The Insulation Properties of Nano Graphene Modified PP/ULDPE Blends
		3.1 Dispersion of Nano Graphene in PP/ULDPE Blends
		3.2 Space Charge Characteristics of PP/ULDPE/Graphene Nanocomposites
		3.3 Conductivity Characteristics of PP/ULDPE/Graphene Nanocomposites
		3.4 Breakdown Strength of PP/ULDPE/Graphene Nanocomposites
		3.5 Trap Characteristics of PP/ULDPE/Graphene Composite
		3.6 Mechanism of Nano Graphene Regulating Electrical Properties of PP/ULDPE Blends
	4 Conclusion
	References
Effect of Mechanical Stress on Space Charge Behaviors of PP Insulation Materials
	1 Introduction
	2 Experimental Arrangement
		2.1 Specimen Preparation
		2.2 Space Charge Measurement
	3 Effects of Mechanical Stretching on Space Charge Behaviors of PP/POE Blend
		3.1 Effect of Mechanical Stretching on Space Charge Characteristics During Polarization Process
		3.2 Effect of Mechanical Stretching on Space Charge Characteristics During Depolarization Process
		3.3 Effect of Mechanical Stretching on Charge Mobility
	4 Effects of Mechanical Stretching on Trap Distributions of PP/POE Blend
	5 Discussion
		5.1 Morphological and Structural Changes of PP/POE Blends Under Mechanical Stretching
		5.2 The Effect of Mechanical Stretching on Carrier Mobility
		5.3 The Effect of Mechanical Stretching on the Total Amount of Space Charge
	6 Conclusion
	References
Space Charge Characteristics of Coaxial Cable Insulation
	1 Introduction
	2 Space Charge Measurement Methods
		2.1 Development of Space Charge Measurement Technology
		2.2 Application of PEA Space Charge Technology
	3 PEA Space Charge Measurement for Coaxial Cables
		3.1 High Voltage Pulse Coupled Injection Method
		3.2 Outer Semiconductor Layer Partial Stripping Injection Method
		3.3 Pulse Measurement Electrode Injection Method
	4 Recovery Algorithm for the Space Charge Waveform in a Coaxial Cable
		4.1 Propagation Principle of a Pressure Wave in a Coaxial Cable
		4.2 Calibration of the Space Charge Distribution in a Coaxial Cable
		4.3 Recovery of Attenuation and Dispersion of the Space Charge in a Coaxial Cable
	5 Space Charge Characteristics of Coaxial Cables
	6 Conclusion
	References
Electric Ageing and Breakdown Phenomenon in Polypropylene Under Complex DC Operating Condition
	1 Introduction
	2 Experimental Arrangement
		2.1 Preparation of PP and PP/Polycyclic Compounds Composites
		2.2 Electrical Tree Experiment System and Analytical Method
	3 Electrical Treeing Initiation and Breakdown Phenomenon Under Impulse Superimposed DC Voltage
		3.1 Experimental Method
		3.2 Electrical Tree Growth Characteristics Under Impulse Superimposed DC Voltage
		3.3 Charge Accumulation Process Under Impulse Superimposed DC Voltage
		3.4 Analysis of the Correlation Mechanism Between Charge Accumulation and Growth Characteristics of Electrical Tree
	4 Polycyclic Compounds Affecting Electrical Tree Growth Under Impulse Superimposed DC Voltage
		4.1 Experimental Method
		4.2 Effect of Polycyclic Compound Kind on Electrical Tree Degradation
		4.3 Effect of Polycyclic Compound Content on Electrical Tree Degradation
		4.4 The Influence Mechanism of Polycyclic Compounds on the Growth Characteristics of Electrical Tree
	5 Conclusion
	References
Conduction and Charge Transport Characteristics of Silicone Rubber Composites with Nonlinear Conductivity
	1 Introduction
	2 Nonlinear Conductivity of SiR/ZnO Composite Insulation
		2.1 Semi-Conductive Additives of ZnO
		2.2 Microstructures of ZnO/SiR Composites
		2.3 Nonlinear Conductivity of ZnO/SiR Composites
	3 Charge Transport of SiR/ZnO Composite Insulation
		3.1 Isothermal Surface Potential Decay Behaviors
		3.2 Correlation Between Nonlinear Conductivity and Surface Charge Dissipation
	4 Charge Transport Under Impulse Superimposed on DC Voltage
		4.1 Surface Charge Distribution Under Impulse Superimposed on DC Voltage
		4.2 Surface Charge Accumulation Under Impulse Superimposed on DC Voltage
		4.3 Effect of ZnO Content on Surface Charge Accumulation
		4.4 Effect of ZnO Content on Surface Charge Transport
	5 Conclusion
	References
Charge Properties of SiC/SiR Composites with Nonlinear Conductivity at Different Temperatures
	1 Introduction
	2 Nonlinear Conductivity
	3 Surface Potential Property Under Homopolar Impulse Superimposed DC Voltage
	4 Surface Potential Property Under Heteropolar Impulse Superimposed DC Voltage
	5 Surface Charge Characteristics of SiR Materials and SiC/SiR Composites Under Positive-Negative Reversal Voltage
	6 Space Charge Characteristics Under DC Voltage
	7 Conclusion
	References
Effect of Temperature and Mechanical Stress on Charge Transport and Ageing Properties of EPDM for Cable Accessories
	1 Introduction
	2 Experiment
		2.1 Sample Preparation
		2.2 Experimental Apparatus and Procedure
		2.3 Modelling and Simulation Methods
	3 Results and Discussion
		3.1 Mechanical Stretching
		3.2 Compressive Stress
		3.3 Electrical Tree Mechanism with Mechanical Stress
		3.4 High Temperature
	4 Conclusion
	References
Theoretical Model and Suppressing Method of Interface Charge Accumulation in HVDC Cable Accessory: A Review
	1 Introduction
	2 Interface Charge Accumulation
		2.1 Space Charge Characteristics in Double-Layer Dielectrics
		2.2 Interface Charge Characteristics Under Voltage Polarity Reversal
	3 Theoretical Model of Interface Charge
		3.1 Maxwell-Wagners-Sillars Theory
		3.2 Bipolar Charge Transport Model
		3.3 Interface Charge Model Based on Quantum Chemical Calculations
	4 Suppression Methods
		4.1 Geometry Design
		4.2 Surface Modification
		4.3 Field Grading Materials
		4.4 Material Selection
	5 Conclusions
	References
Polymer Insulation for HVDC GIS/GIL
Epoxy Resin Insulating Composites for Vacuum Cast Electrical Insulators of GIS
	1 Introduction
	2 Residual Stress of Epoxy Composites Under Different Cooling Methods
		2.1 Experimental
		2.2 Results and Analysis
		2.3 Conclusion
	3 Insulating Properties of Epoxy Composites with Curing Shrinkage Marks
		3.1 Experimental
		3.2 Results and Analysis
		3.3 Conclusion
	4 Thermal Aging Mechanism of DGEBA Epoxy Resin for Vacuum Cast Electrical Insulators
		4.1 Modeling and Calculation
		4.2 Results and Analysis
		4.3 Conclusion
	5 Improving the Properties of Epoxy Composite Insulation Materials by Chain Extension
		5.1 Experimental
		5.2 Results and Analysis
		5.3 Discussion
		5.4 Conclusion
	References
HVDC Spacers by Adaptively Controlling Surface Charges
	1 Introduction
	2 Design Concept
		2.1 Shape Optimization
		2.2 Material Modification
	3 Nonlinear Conductivity
	4 Sample Preparation
	5 Mechanical Property
		5.1 Mechanical Stress Simulation
		5.2 Water Pressure Test
	6 Electrical Property
		6.1 DC Surface Flashover Results
		6.2 AC Surface Flashover Results
		6.3 Discussion
	7 Future Work
		7.1 Controlling the Electrical Performance of Composites based on SiC Doped Epoxy
		7.2 Electrical Performance Equivalence Considering Size Effect and Tests Under Temperature Gradient
	8 Conclusion
	References
Surface Charge Accumulation on Insulators in HVDC Gas-Insulated Systems: Measurement, Characteristics, and Suppression
	1 Introduction
	2 Surface Charge Measurement
		2.1 Basic Principle of Measurement
		2.2 Inversion Algorithm for Shift-Variant Systems
	3 Characteristics of Surface Charge Accumulation
		3.1 Surface Charge Accumulation in Air and SF6
		3.2 Surface Charge Accumulation Patterns
		3.3 Verification of the Uniform Surface Charging Pattern
	4 Surface Charge Suppression Methods
		4.1 Suppress Bulk Current to Decrease the Uniform Charging Level
		4.2 Promote Surface Charge Dissipation to Reduce Charge Speckles
	5 Summary
	References
Nano-Modification for Enhancing the DC Surface Insulation Strength of Epoxy Resin
	1 Introduction
	2 Nano Doping for Enhancing the Surface Insulation of ER
		2.1 Nano-SiO2
		2.2 Nano-Al2O3
		2.3 Nano-TiO2
		2.4 BN Nanosheets
		2.5 Other Nano-Fillers
	3 Nano Functionalization for Enhancing the Surface Insulation of ER
		3.1 Coupling Agent Treatment of Nano Fillers
		3.2 Morphology Control of Nano Fillers
		3.3 Rare Earth Element Doping of Nano-Fillers
		3.4 Plasma Fluoridation Treatment of Fillers
	4 Mechanism of Filler Doping and Its Functionalization
	References
Electric Field Regulation Along Gas–Solid Interface in HVDC GIL with Nonlinear Conductivity Material
	1 Introduction
	2 Electrical Conductivity of Epoxy/SiC Composites
		2.1 Sample Preparation
		2.2 Conductivity Measurement
	3 Application of Epoxy/SiC Composites in Novel Spacers
		3.1 Concept of Surface Nonlinear Conductivity Spacer
		3.2 Parameter Optimization of Surface Nonlinear Conductivity Spacer
	4 Fabrication and Electrical Evaluation of Novel Spacers
		4.1 Dip Coating
		4.2 Centrifugation
		4.3 Gradient Sputtering
		4.4 Flashover Test
	5 Conclusion
	References
Surface Molecular Structure Modified Epoxy Resin Materials for HVDC GIL Spacer
	1 Introduction
	2 Insulator with Graded Conductivity SFGM
		2.1 The Concept of Novel Insulator with SFGM
		2.2 Fabrication of Insulator with Conductivity SFGM
		2.3 Electrical Field Distribution Based on the Simulation
		2.4 Improved Flashover Voltage
	3 Insulator with Continuous Conductivity SFGM
		3.1 SFGM Fabrication by Temperature-Controlled Fluorination
		3.2 Optimization of the Insulator with Continuous SFGM
		3.3 Electric Field Calculation
	4 Conclusion
	References
Plasma Surface Treatment of Al2O3-Filled Epoxy Resin for Accelerating Surface Charge Dissipation
	1 Introduction
	2 Experimental Setups
		2.1 Sample Preparation
		2.2 Sample Treatment
		2.3 Surface Potential and Dielectric Parameters
		2.4 Flashover Voltage Test
		2.5 Surface Morphology and Chemical Composition
	3 Accumulation and Dissipation Characteristics
		3.1 Surface Charge Accumulation Before and After the Treatments
		3.2 Surface Charge Dissipation Before and After the Treatments
		3.3 Surface Charge Dissipation After the Storage
		3.4 Flashover Voltage Measurement Before and After the Treatments
	4 Surface Property Analysis
		4.1 Surface Morphology
		4.2 Chemical Component
		4.3 Surface and Bulk Resistivity
		4.4 Trap Density Distribution
	5 Discussion
	6 Conclusion
	References
Promising Functional Graded Materials for Compact Gaseous Insulated Pipelines
	1 Introduction
	2 Electric Field Distribution in GIS/GIL
		2.1 Electric Field Under AC Voltage
		2.2 Electric Field Under DC Voltage
		2.3 Electric Field Under Transient Voltage
		2.4 Electric Field and Long-Term Performance
	3 Bulk FGM Insulator for Compact GIS/GIL
		3.1 Origins of FGM Insulators
		3.2 Fabrication of Bulk FGM Insulators
	4 Optimizing Dielectric Parameter Distribution of FGM Insulator
		4.1 Iterative Optimization
		4.2 Topology Optimization
		4.3 Particle Swarm Optimization
	5 Surface FGM Insulator for Compact GIS/GIL
		5.1 Concept of SFGM
		5.2 Fabrication of SFGM Insulator
	6 Conclusion
	References
Surface Functionally Graded Insulator for High Voltage Gas Insulated Apparatus
	1 Introduction
	2 Concept of SFGM
	3 Fabrication of SFGM Spacer
		3.1 Magnetron Sputtering
		3.2 Characterization of BaTiO3Layer
		3.3 SFGM Spacer Fabrication Method
		3.4 Dielectric Parameters Measurement
	4 Electric Field Simulation
		4.1 Simulation Model
		4.2 Effect of Sputtering Layer Permittivity
		4.3 Effects of Sputtering Layer Thickness
		4.4 Application of Prepared Spacers
	5 Flashover Test Results
	6 Conclusion
	References
Mechanical Reliability of Large-Scaled Epoxy Insulator in GIS
	1 Introduction
	2 Experimental Setup
		2.1 Density Measurement
		2.2 Mechanical Property Measurement
	3 Simulation Model
		3.1 Al2O3Settlement
		3.2 Mechanical Stress
	4 Results and Discussion
		4.1 Density Distribution
		4.2 Mechanical Property
		4.3 Stress Distribution and Laying Method
	5 Conclusion
	References
Insulation Design of Superconducting Gas Insulated Transmission Line
	1 Introduction
	2 E-Field Adaptive Insulator
		2.1 The Model of the S-GIL Design
		2.2 Simulation Design of E-Filed Adaptive Insulator
		2.3 Results and Discussion
		2.4 Summary
	3 Insulator with Surface Graded Material
		3.1 The Model of the S-GIL Insulator
		3.2 Simulation of Surface Conductivity Gradient Insulator
		3.3 Results and Discussion
		3.4 Summary
		3.5 Conclusion
	References
Polymer Insulation for HVDC Capacitors
Polymer Dielectrics for Film Capacitors Applied in HVDC Transmission
	1 Introduction
	2 Polymer Film Capacitors and Their Applications in HVDC Transmission
	3 Requirements for Capacitor Polymer Dielectric Materials
		3.1 Energy Storage Performance
		3.2 Relative Permittivity and Dissipation Factor
		3.3 Breakdown Strength and Leakage Current
		3.4 Self-clearing Capability, Processability and Thermal Stability
	4 Advanced Polymer Dielectric Materials
		4.1 Classification of Polymer Dielectrics
		4.2 Linear Dielectric Polymers
		4.3 Ferroelectric Polymers
		4.4 Multilayer Dielectric Polymers
		4.5 Polymer Nanocomposites
	5 Conclusion
	References
Improvement of Dielectric Properties of Polypropylene Film for HVDC Metallized Film Capacitors
	1 Introduction
	2 Dielectric Properties Dependent on Crystalline Morphology of PP Film for HVDC Capacitors Application
		2.1 Experimental Arrangement
		2.2 Results
		2.3 Discussion
	3 Effect of Crystallization Regulation on the Breakdown Strength of Metallized Polypropylene Film Capacitors
		3.1 Experimental Preparation
		3.2 Results
	4 Conclusion
	Reference
High Temperature Dielectric Materials for Electrical Energy Storage
	1 Introduction
	2 Key Parameters of High Temperature Dielectric Materials
		2.1 Dielectric Constant and Dielectric Loss
		2.2 Conduction and Breakdown Strength
		2.3 Thermal Parameter
	3 Measurement of Energy Storage Property
		3.1 D-E Hysteresis Loop Test
		3.2 Discharge Test
	4 Energy Storage of Polymer-Based Dielectrics
		4.1 Polymer-Based Nanocomposites with 0D Fillers
		4.2 Polymer-Based Nanocomposites with 1D Fillers
		4.3 Polymer-Based Nanocomposites with 2D Fillers
		4.4 Polymer-Based Inhomogeneous Dielectrics
	5 Conclusion
	References