The Proceedings of 2023 4th International Symposium on Insulation and Discharge Computation for Power Equipment (IDCOMPU2023): Volume II (Lecture Notes in Electrical Engineering, 1101)

Contents Mixed Three-Parameter Weibull Breakdown Distribution Model and Breakdown Mechanism of Metalized Films 1 Introduction 2 Mixed Three-Parameter Weibull Distribution Model 3 Experiment Setup 4 Results and Discussion 5 Conclusion References Risk Assessment of DC Bias in Multi DC Projects Under Different Operating Conditions 1 Introduction 2 DC Bias Simulation Model 2.1 General Overview of Central China Power Grid 2.2 Geographic Information Modeling 2.3 DC Current Modeling 3 Risk Analysis of DC Bias Under Different Operating Conditions 3.1 Risk Analysis of DC Bias Magnetization Under the Action of a Single DC Project 3.2 Risk Analysis of DC Bias Under the Action of Multiple DC Projects 4 Risk Analysis of DC Bias Magnetization Under Different Operation Modes 4.1 DC Bias Current 4.2 DC Bias Risk Theory for Superimposed Multiple DC Projects 5 Conclusion References Molecular Simulation of ZnBDC Adsorption for C4F7N/CO2 and Its Decomposition Products 1 Introduction 2 Simulation Details 2.1 Adsorption Model 2.2 GCMC Simulation 3 Results and Discussion 4 Conclusion References Study on the Surface Charge Accumulation and Dispersion Process of Polyimide for New Cables 1 Introduction 2 Method for Calculating Surface Charge of Polyimide Polymers 3 Surface Charge Measurement Experiments 3.1 Preparation of Test Sample 3.2 Charge Measurement System 3.3 Surface Charge Accumulation and Dissipation Experiments 4 Measurement Results and Analysis 4.1 Surface Charge Accumulation 4.2 Surface Charge Dissipation 4.3 Surface Charge Distribution 5 Conclusion References Improvement of Flashover Voltage of Epoxy Resin by Large-Area Dielectric Barrier Discharge 1 Introduction 2 Experimental Section 2.1 Material 2.2 DBD Plasma Experimental Platform 2.3 Surface Electrical Performance Testing Platform 2.4 Material Characterization 3 Results and Discussion 3.1 Effect of HMDSO on Discharge Characteristics 3.2 Physical Morphology and Chemical Composition Characterization of Epoxy 3.3 Surface Conductivity Testing and Analysis 3.4 Flashover Voltage Testing and Analysis 3.5 Analysis of the Modification Mechanism 4 Conclusion References Electric Field Simulation Analysis of Typical Defects of Main Insulation Burrs in Power Transformers 1 Introduction 2 Transformer Main Insulation Simulation Model 2.1 Modeling of the Main Insulation 2.2 Boundary Conditions 3 Simulation Results and Analysis 3.1 Electric Field Analysis of Burr-Free Defects 3.2 Burr Defects in Insulated Cardboard 3.3 Static Rings with Burr Defects 4 Conclusion References The Effect of Inlet Wind Speed on the Performance of Electrostatic Precipitation Systems and Double Rotating Venturi Systems 1 Introduction 2 Working Principle of a New Type of Double Rotating Venturi Dust Collector 3 COMSOL Turbulence Model 4 Results and Discussion 4.1 Characteristic Analysis of Electrostatic Precipitator 4.2 Characteristic Analysis of Double Rotating Venturi Dust Collector 5 Conclusion References Two-Dimensional Numerical Simulation of Temperature Field Distribution in Transformer Windings 1 Introduction 2 Heat Generation and Heat Dissipation Analysis 2.1 Heat Generation Analysis of Transformer Windings 2.2 Heat Dissipation Analysis of Transformer Winding 3 Differential Equations and Boundary Conditions 4 Simulation Example of Temperature Field of Transformer Winding 4.1 Two-Dimensional Finite Element Model of Transformer Winding 4.2 Mesh Subdivision 4.3 Parameter Setting 4.4 Calculation Results and Analysis 5 Conclusion References Permeation Characteristic Comparison of the Components in the Rejuvenation Liquid of Polyethylene 1 Introduction 2 The Components of the Rejuvenation Liquid 3 Molecular Dynamics Simulation 4 Finite Element Simulation of Chemical Substance Transfer 5 Discussion 6 Conclusion References Optimization of Capacitor Core Parameters for Rubber-Impregnated Fiber Bushing of Ultra-High Voltage AC Transformer 1 Introduction 2 Building a Finite Element Model 2.1 Structure and Initial Parameters of UHV Bushing 2.2 Establishment of Finite Element Simulation Model and Condition Loading 3 Simulation Analysis of Bushing Electric Field 3.1 Comparison of Methods 3.2 Electric Field Distribution of Capacitor Cores 4 Structural Optimization 4.1 Structural Optimization of Capacitor Cores and Electric Field Analysis 5 Conclusion References Study on Factors Influencing Self-healing Energy of Metallized Film Capacitors 1 Introduction 2 Experimental Platform and Experimental Protocol 3 Experimental Results and Analysis 3.1 Effect of Voltage on Self-healing Energy 3.2 Effect of Temperature on Self-healing Energy 3.3 Effect of Parallel Capacitance on Self-healing Energy 3.4 Effect of Film Thickness on Self-healing Energy 3.5 Effect of Interlayer Pressure on Self-healing Energy 4 Conclusion References Construction of a Novel Insulation State Evaluation System for XLPE Cable 1 Introduction 2 XLPE Cable Insulation Data Online Monitoring 2.1 XLPE Cable Introduce 2.2 A Subsection Sample 3 Data Processing 3.1 Data Normalization Processing and Correlation Analysis 3.2 Multi-parameter Linear Regression Model 4 Conclusion References Fault Diagnosis Method of Impulse Impedance Characteristic Spectrum Based on Naive Bayes Classifier 1 Introduction 2 Diagnostic Principle of Impulse Impedance Characteristic Spectrum Method 2.1 Impulse Impedance and Frequency Response Testing Techniques 2.2 Fault Diagnosis Technology Based on Naïve Bayes Classification 2.3 Selection of Fault Categories for Grounding Grids 3 Example Analysis 4 Conclusion References Calculation of Temperature Distribution of GIS Bus Bar Under Multi-physical Field Coupling 1 Introduction 2 Multiple Physical Field Coupling Mathematical Model 2.1 Governing Equation of Electromagnetic Field 2.2 Governing Equation of Temperature Field and Flow Field 3 GIS Simulation Model and Parameter Setting 4 Simulation Result 4.1 Magnetic Field Simulation 4.2 Temperature Field Simulation 5 Conclusion References The Inversion Calculation Method of Core Temperature in 110 kV Cable Inter-mediate Joint 1 Introduction 2 Intermediate Joint Samples and Material Parameters 3 Inversion Calculation Method for Distributed Thermometers 4 Intermediate Joint of 110 kV Cable Temperature Field Simulation 5 Correction of Inverse Calculation Method Considering Contact Resistance 6 Discussion 7 Conclusion References Effect of Metal Fouling on Insulator Surface on the Decomposition Characteristics of SF6/N2 Gas Mixture 1 Introduction 2 Experimental Setup 3 Result 3.1 Variation of Characteristic Component Content with Time and PD Intensity 3.2 Variation of Characteristic Component Content with PD Intensity 3.3 The Effective Formation Rate of Characteristic Component 4 Conclusion References Evaluation of the Arc Characteristics of High-Velocity Flows in Semi-closed Spaces Through Simulation 1 Introduction 2 Movement Model of High Airflow Impact Arc 3 Simulation of High-Speed Airflow Impact of the EAAELP Device 3.1 Geometrical Model and Parameter Setting 3.2 Analysis of EAAELP Device Simulation Results 4 Simulation of the SMAELP Device 4.1 SMAELP Device Geometry Modeling and Parameter Setting 4.2 Analysis of the Simulation Results of the SMAELP Device 5 Simulation of Arc-Off Process of the EAA–SMA Device 5.1 EAA–SMA Device Geometry 5.2 Analysis of the Simulation Results 6 Conclusions References Characteristics of PD Decomposition of SF6/N2 Gas Mixture Under Metal Protrusion Defects 1 Introduction 2 Experimental Setup 3 Result 3.1 Variation of Characteristic Component Content with Time and PD Intensity 3.2 The Effective Formation Rate of Characteristic Component 4 Conclusion References Research on Insulator Defect Detection in Power Inspection Images Based on PaddleDetection 1 Introduction 2 Insulator Defect Monitoring 2.1 YOLOv3 Algorithm 2.2 PP-YOLOv2 Based Insulator Defect Detection 3 Experimental Results and Analysis 3.1 Dataset Settings 3.2 Results Analysis 4 Conclusion References Influence of Micro-water on Insulation and Decomposition Characteristics of SF6/N2 Mixtures 1 Introduction 2 Experiment Platform and Method 3 Result and Discussion 3.1 Effect of Different Micro-water Content on the Decomposition Characteristics 3.2 Effect of Different Micro-water Content on the Insulation Performance 4 Conclusion References Arc Motion Behavior During Rotary Separation of Vacuum Contacts 1 Introduction 2 Experiment System 3 Results and Discussion 3.1 Arc Movement of Different Contact Separation Methods 3.2 Arc Images Processing for Different Contact Separation Methods 3.3 Vacuum Arc Voltage Characteristics of Different Contact Separation Methods 4 Conclusions References Research on Full-Circuit Model of Damping Busbar for VFTO Suppression 1 Introduction 2 Establishment of Full-Circuit Equivalent Model of Damping Busbar 3 Calculation of Full-Circuit Parameters for Damping Busbar 3.1 Calculation of Inductance Parameters 3.2 Calculation of Capacitance Parameters 3.3 Calculation of Breakdown Impedance 3.4 Full-Circuit Model of Damping Busbar 4 Analysis of Effect of Full-Circuit Parameters on VFTO Suppression 5 Summary References Sampling Inspection Method of Power Grid Materials Based on Analytic Hierarchy Process 1 Introduction 2 Data Cleaning 2.1 Text Matching 2.2 Database of Quality 3 Analytic Hierarchy Process 3.1 Model Establishment 3.2 Establish Hierarchical Structure Model 3.3 Constructing Judgement Matrix 3.4 Consistency Checking 3.5 Geometric Mean Method to Calculate Weight 4 Results of Quality Level and AQL 4.1 Quality Level 4.2 Determine the Value of AQL 5 Conclusion References Analysis of Damage Expansion and Mechanical Strength in End Insulation for High-Power AC Motor with Initial Defects 1 Introduction 2 End Winding Force Analysis Theory 2.1 Electromagnetic Force Analysis Theory 2.2 Analysis Theory of Dynamic Mechanical Stress 2.3 Fracture Analysis 3 Numerical Examples and Results Analysis 3.1 Motor and End Winding Parameters 3.2 Three-Dimensional Finite Element Electromagnetic Force Calculation 3.3 Mechanical Calculation of Insulating Layer 3.4 Insulation Layer Crack Calculation and Analysis References The Influence Mechanism that Micro Grain-Boundary Structure Parameters of ZnO Varistor to the Macroscopic Electrical Characteristics 1 Introduction 2 Model and Parameter Selection 2.1 Model of Gain Boundary 2.2 Performance Parameters and Equivalent Model 3 Effect of Double Schottky Barrier on Electrical Properties 4 Influence of Different Grain Boundary Zoning 4.1 Influence of Regional Ratio of Thick Intercrystalline Phase 4.2 Effect of Grain Contact Region Proportion 5 Discussion on Influence Mechanism 6 Conclusion References Numerically Investigating Interturn Arcing Faults Inside a UHV Converter Transformer 1 Introduction 2 Theoretical Modeling 2.1 Internal Electromagnetic Field 2.2 External Electric Circuit 2.3 Coupled Field-Circuit Analysis 3 Simulation and Discussion 3.1 Simulation Setup 3.2 Typical Results 4 Conclusion References A Numerical Study on Oil Pressure Rise Caused by Arcing Faults Inside a Converter Transformer 1 Introduction 2 Theoretical Modeling 2.1 The Dynamics Model for Gas Bubble 2.2 Fluid Model 2.3 Bubble-Fluid Interaction 3 Simulation and Discussion 3.1 Simulation Model 3.2 Typical Results 4 Conclusion References Thermal Characteristics of 10 kV Cable Joints Under Defects in the Crimping Process 1 Introduction 2 Thermal Characteristic Calculation Model 2.1 Principles of Thermal Characteristic Calculation 2.2 Calculation Model 3 Calculation Results and Analysis of Thermal Characteristics 3.1 Temperature Distribution Characteristics 4 Conclusions References Simulation of Mechanical Characteristics of Contact Group During the Switching Process of On-Load Tap Changer 1 Introduction 2 Modeling Methods 3 Simulation of Action Characteristics 3.1 The Influence of Spring Stiffness Coefficient 3.2 The Influence of Contact Curvature Radius 3.3 The Influence of Different Initial Velocities 4 Conclusion References Structural Dynamic Analysis and Static Stability Analysis of Drum-Type Self-Standing Power Transmission Towers 1 Introduction 2 Establishment of Finite Element Model for the Power Transmission Tower 3 Principles of Modal Analysis and Buckling Analysis 3.1 Principles of Modal Analysis 3.2 Principles of Buckling Analysis 4 Modal Analysis Results of the Power Transmission Tower 5 Buckling Analysis Results of the Power Transmission Tower 5.1 Eigenvalue Buckling Analysis Results 5.2 Nonlinear Buckling Analysis Results 6 Conclusion References Identification of Construction Defects in 10 kV Cable Intermediate Joints Based on Canny Algorithm 1 Introduction 2 10 kV Cable Defect Types and Characteristics 3 Canny-Based Edge Detection and Part Segmentation 3.1 Algorithm Flow 3.2 Gaussian Filtering of Cable Defect Images 3.3 Cable Defect Image Gradient Amplitude and Direction 3.4 Non-extreme Value Suppression 3.5 Double Threshold to Solve for Image Edges 4 Experimental Analysis 4.1 Identification of Defects in the Main Insulation Stains and Scratches 4.2 Comparison of Different Algorithms 5 Conclusion References Identification of Typical Construction Defects of 10 kV Cable Intermediate Joints Based on SIFT Algorithm and Canny Algorithm 1 Introduction 2 10 kV Cable Image Acquisition and Features 3 Image Stitching Based on SIFT Algorithm 3.1 Construction of the Scale Space 3.2 Positioning of Feature Points 3.3 Calculation of Gradient Amplitude and Angle 3.4 Stitching Effect of Images 4 Canny-Based Edge Detection and Part Segmentation 4.1 Algorithm Flow 4.2 Gaussian Filtering of Cable Defect Images 4.3 The Gradient Amplitude and Direction of the Image 4.4 Non-extreme Value Suppression 4.5 Double Threshold to Solve for Image Edges 5 Experimental Analysis 5.1 Identification of Crimp Tube Burr and External Semi-conductive Defects 5.2 Defect Quantification Accuracy 6 Conclusion References Analysis of Lightning Activity Over Cambodia, 2021 1 Introduction 2 Data 3 Result 3.1 Temporal Variation of Lightning Activity Over Cambodia 3.2 Spatial Distribution of the Lightning Flash Activities 3.3 Lightning Polarity Distribution 3.4 Characteristics of the Lightning Current Intensity Distribution 4 Conclusions References Mechanism Analysis of Insulator Fault in Enclosed Isolated Phase Bus Caused by Vibration 1 Introduction 2 Structure of Enclosed Isolated Phase Bus 2.1 Structure and Layout of Insulator 2.2 Force Analysis of Insulator 3 Mechanism of Vibration-Induced Insulator Failure 3.1 Vibration Characteristics of Insulators with Air Gap 3.2 Vibration Characteristics of Insulators with Crack 4 Simulation Verification 4.1 Vibration Characteristics of Insulator with Air Gap 4.2 Vibration Characteristics of Insulator with Cracks 5 Conclusion References Study on the Influence Mechanism of Voltage on Sulfide Corrosion in Power Transformer 1 Introduction 2 Molecular Dynamics Simulations on the Effects of Electric Field on Sulfur Corrosion 2.1 Model Building and Simulation Process 2.2 Elastic Modulus of Cellulose 2.3 Mean Square Displacement of Cellulose 3 Simulation Results with Experimental Verification 3.1 Experimental Materials and Test Procedures 3.2 Test Results and Analysis 4 Conclusions References Level Set Method Assisted Topology Optimization of Permanent Magnet Synchronous Machine 1 Introduction 2 Level Set Topology Optimization Algorithm 3 Topology Optimization of Magnetic Actuator 4 TO of Permanent Magnet Synchronous Motor (PMSM) 4.1 Size Optimization of Permanent Magnet for Reducing Torque Ripple 4.2 Topology Optimization of Rotor Region 5 Conclusion References A New Method of Lithium Battery Insulation Fault Diagnosis Based on Double Kalman Filter 1 Introduction 2 Establishment of Battery Pack Insulation Fault Detection Model 3 Parameter Identification Based on Double Extended Kalman Filter Algorithm 4 Experimental Verification 5 Conclusion References Study on the Temperature Rise Performance of Propellant-Assisted Interrupter Propellant Chamber 1 Introduction 2 Composition of Propellant-Assisted Interrupting and Arc Triggered Hybrid Current Limiting Fuse 3 Modeling Temperature Rise and Analysis 3.1 Thermoelectric Coupling Model 3.2 Simulation Results and Analysis 4 Test Verification 5 Conclusion References Simulation of Hot Spot Temperature Rise of Dry Bridge Reactor Based on Highly Conductive Epoxy Composites 1 Introduction 2 Dry Air-Core Reactor 2.1 Basic Structure of Dry Air-Core Reactor 2.2 Working Principle of Dry Air-Core Reactor 3 Temperature Field Simulation Study of Dry-Type Hollow Reactors Under Normal Conditions 3.1 Establish a Dry Air-Core Reactor Simulation Model 3.2 Coupling Analysis of Flow Field and Temperature Field 3.3 Temperature Field Simulation Results of Dry Air Core Reactor Under Normal Conditions 4 Simulation Study on the Effect of Conventional/highly Conductive Epoxy Materials on the Reactor Hotspot Temperature Rise 4.1 Simulation Calculation of Thermal Conductivity Performance of Conventional/high Thermal Conductivity Epoxy Composites 4.2 Influence of Conventional/high Thermal Conductivity Epoxy Materials on the Temperature Rise of Reactor Hot Spots 5 Conclusion References Research on Short Circuit Cumulative Effect and Deformation Prediction Method of Transformer Windings 1 Introduction 2 Analysis of Short Circuit Effect and Deformation Characteristics of Transformer Windings 2.1 Calculation of “Magnetic Field and Circuit” 2.2 Transformer Deformation Calculation 3 Finite Element Simulation Analysis Model of Transformer 3.1 Introduction of the Model 3.2 3-D Finite Element Simulation Model of Transformer 4 Simulation Results and Analysis of Transformer Short Circuit Shocks 5 Conclusion References Scramjet Plasma Ignition and Assisted Combustion Technology Review 1 Introduction 2 Mechanism of Plasma Ignition and Combustion 3 Plasma-Promoted Fuel Mixing 4 Ignition of Plasma 4.1 Plasma Jet Ignition 4.2 Arc/Gliding Arc Plasma Ignition 4.3 Laser-Induced Plasma Ignition 4.4 Microwave Discharge Plasma Ignition 4.5 Multi-point and Combined Plasma Ignition 5 Plasma-Enhanced Combustion 5.1 Plasma Jet Enhanced Combustion 5.2 Arc/Gliding Arc Plasma-Enhanced Combustion 5.3 Microwave Plasma-Enhanced Combustion 6 Conclusions References Investigation on Intelligent Drone-Mounted Mobile Vehicle for Power Transmission Line Inspection 1 Introduction 2 Drone-Mounted Mobile Vehicle 3 Communication System 3.1 5G-BeiDou Satellite Communication System 3.2 Phased Array Antenna 4 Autonomous Flight Test and Application 4.1 Precision Landing 4.2 Take-Off Performance 5 Conclusions References Voltage Transformer Fault Diagnosis Based on Improved ResNet50 1 Introduction 2 Voltage Transformer Fault Model Voltage Transformer Fault Model 2.1 Fixed Deviation Fault 2.2 Drift Deviation Fault 2.3 Complete Failure Failure 3 Residual Neural Network 3.1 Introduction to the Main Framework of Residual Neural Network 3.2 Residual Block Structure 3.3 Principle of Batch Normalization 4 Experimental Results References Fuzzy Logic Approach for Life Time Estimation of Polyimide (PI) Insulations Used at High-Frequency 1 Introduction 2 Experiment Setup 3 Fuzzy Logics 4 Experimental Results Analysis 5 Fuzzy Logic Life Time Estimation Model 5.1 Membership Functions 6 Interaction Between Parameters 7 Conclusion References Quantum Mechanism of Insulation Degradation Induced by Charge Relaxation in Silicone Gel Under the Ultrafast Pulsed Electric Field 1 Introduction 2 Theory and Methods 2.1 Tight-Binding Su–Schrieffer–Heeger (SSH) Model 2.2 Marcus Theory 3 Results and Discussion 4 Conclusion References Multi-objective Optimization of Permanent Magnet Actuator Based on Surrogate Model 1 Introduction 2 OLS-RBF Surrogate Model 3 Introduction of Improved NSGA-III 3.1 Overview of NSGA-III 3.2 Improvements of the Selection Mechanism 4 Simulation and Verification of Multi-objective Optimization Based on Surrogate Model 4.1 Surrogate Model Training of Electromagnetic Needle Selector with Permanent Magnet 4.2 Multi-objective Optimization Results 5 Conclusions References Contact Defects Diagnosis and Load Capacity Estimation for Double-Fracture Disconnect Switchgear 1 Introduction 2 Thermal Network Model for DDS 3 Diagnosis of Contact Defects and Estimation of Load Capacity for DDS 3.1 Diagnosis of Contact Defects 3.2 Estimation of Load Capacity 4 Experimental Verification 4.1 Experimental Configuration 4.2 Experimental Results 5 Conclusion References SDBD Enhanced Supercombustion Chamber Blending Characteristics Simulation Studies 1 Introduction 2 Simulation Model and Boundary Conditions 3 Simulation Results and Analysis 3.1 Effect of Excitation Position on Blending Effect 3.2 The Effect of Incentive Form on Blending Effect 4 Conclusion References Research on the Braking Characteristics of Electromagnetic Eddy Current Braking 1 Introduction 2 Working Principle 3 Finite Element Analysis of Transient Magnetic Field 3.1 Parameter Settings 3.2 Result Analysis 4 Research on the Influence of Various Factors on Torque 4.1 Research on the Influence of Rotational Speed on Torque 4.2 Research on the Effect of Excitation Current on Torque 5 Conclusion References Design and Simulation Analysis of a New Air-Core Permanent Magnet Compensated Pulsed Alternator with Segmental Squirrel-Cage 1 Introduction 2 Design Basis and Scheme 2.1 Stator Design 2.2 Rotor Design 3 Simulation and Verification 3.1 No-Load Characteristic Analysis 3.2 Discharge Characteristic Analysis 4 Conclusion References Influence of Insulating Cylinder on Electric Field Inside Cast-Resin Dry-Type Power Transformer 1 Introduction 2 Model Building 3 Calculation Results and Analysis of Electric Field 3.1 Electric Field Distribution of Original Model 3.2 Influence of the Insulating Cylinder’s Position on the Electric Field 3.3 Influence of the Insulating Cylinder’s Quantity on the Electric Field 3.4 Influence of the Insulating Cylinder’s Relative Permittivity on the Electric Field 3.5 Influence of the Insulating Cylinder on the Electric Field in the Main Air Channel 4 Conclusions References Modeling and Application of Transformer Degradation Development Law Based on Degradation Track 1 Introduction 2 Degradation-Based Reliability Theory 2.1 Degradation-Based Reliability Modeling Approach 2.2 Degradation-Based Reliability Modeling Analysis Process 3 Modeling of Transformer Degradation Development Law 3.1 Transformer Degradation Process Model Selection 3.2 Determination of Oil Chromatography Attention Values 3.3 Transformer Degradation Track Modeling 3.4 Application Method of the Degradation Track 4 Conclusion References Impact of Typical Structural Parameters on Hotspot Temperature Rise in Dry-Type Bridge-Arm Reactors: A Simulation Study 1 Introduction 2 Reactor Basic Structure and Model 2.1 The Basic Structure 2.2 Working Principle and Model 3 Multi-physical Field Coupling Analysis 3.1 Model Assumption 3.2 Model Boundary Condition 3.3 Mesh Generation 3.4 Simulation Results of Temperature Field 4 Influence Law of Structural Parameters 4.1 Experimental Design 4.2 Influence Law 4.3 Structure Optimization 5 Conclusion References Multi-physics Based Temperature Distribution Simulation of HVAC Submarine Cable at Various Velocity 1 Introduction 2 The Simulation Model 2.1 Geometric Model 2.2 Control Equations 2.3 The Boundary Conditions 2.4 Solution Method 3 Results and Discussion 3.1 Temperature Field Distribution Under Static Seawater 3.2 Effects of Seawater Velocity 4 Conclusions References Rapid Recovery of Voltage Sag in Distribution Network Based on Dq Transformation 1 Introduction 2 Compensation Strategy of Dynamic Voltage Restorer 3 Emulation Proof 4 Experimental Verification 5 Conclusion References Metering Fault Diagnosis Model Based on Deep Feature Fitting Network with Mixture of Experts 1 Introduction 1.1 Fault Diagnosis Based on Expert System 1.2 Fault Diagnosis Based on Learning 1.3 Mixture of Experts and Feature Fitting Networks 2 Metering Fault Diagnosis GNN Model 2.1 Types of Metering Equipment Failures 2.2 GNN Model for Fault Diagnosis of Metering Equipment 3 Experiment 3.1 Experiment Analysis 4 Conclusion References Calculation and Measurement of Sequence Parameters of Three-Core Submarine Cable with Semi-conductive Sheaths 1 Introduction 2 Structure and Material Parameters of the Three-Core Submarine Cable 3 Sequence Parameter Calculation for the Three-Core Submarine Cables 3.1 Simulation Based on Multi-conductor System Modeling 3.2 Estimation of Sequence Parameters Based on IEC Formulas 4 Measurement of Sequence Parameters of the Three-Core Submarine Cable 5 Comparison and Analysis of Calculated and Measured Results 6 Conclusion References Finite Element Equivalent Heat Transfer Coefficient Solution for Transformer Windings Based on Asymptotic Homogenization Method 1 Introduction 2 Asymptotic Homogenization Equivalent Heat Transfer Coefficient Solution 3 Simulation Simplification Example Analysis 3.1 Transformer Winding Simulation Model and Unit Cell Model 3.2 Calculation of Equivalent Heat Transfer Parameters for Windings 3.3 Simplified Model of Winding and Temperature Field Calculation 4 Conclusion References Partial Discharge Location Method for Oil-Impregnated Pressboards Based on PSO Algorithm 1 Introduction 2 Simplification of Electrostatic Field Models for Measurement Systems 3 Mathematical Models for Solving Inverse Problem 3.1 Multi-layer Media Mirroring 3.2 Characterization of Electrostatic Field Inverse Problems 3.3 Objective Function Characterization 4 Data Processing 5 Results and Analysis 6 Conclusion References Hot Spot Temperature Prediction of Transformer Windings Naturally Cooled by Internal Oil Based on Thermoelectric Analogy Principle 1 Introduction 2 Calculation Method of Transformer Hot-Spot Temperature 2.1 Calculation Model of Top Oil Temperature of ONAN Cooling Mode Transformer 2.2 Hot Spot Temperature Calculation Model of ONAN Cooling Mode Transformer 3 Example Verification and Result Analysis of Thermal Model 4 Conclusion References Study on Thermal Stability of OPGW in Distribution Line During Lightning Striking and Grounding Short Circuit Faults 1 Introduction 2 Distribution Network OPGW Temperature Distribution Calculation Model and Typical Parameters 2.1 Distribution Network OPGW Temperature Rise Distribution Calculation Equation and Parameters 3 Analysis of the Influence of Temperature Rise Characteristics of Distribution Network OPGW Under the Condition of 2 Short Circuit Fault 3.1 Analysis of Temperature Rise Characteristics of OPGW Under Single-Phase Grounding Fault 3.2 Analysis of Temperature Rise Characteristics of OPGW Under Two-Phase Short Circuit Fault 4 Analysis on the Influence of Temperature Rise Characteristics of OPGW Under Lightning Strike Fault 4.1 Analysis of Temperature Rise Characteristics Under Single Lightning Strike Condition 5 Conclusion References Effect of Humidity on Negative Streamer Discharge in Short Air Gap 1 Introduction 2 Mathematical Model and Parameters of Streamer Discharge Process 2.1 Mathematical Equations of Charged Particle Development and Space Electric Field Coupling 2.2 Correction Method of Discharge Parameters Considering Humidity Effect 2.3 Air Gap Geometry and Boundary Conditions 3 Parameters and Model Feasibility Verification 4 Streamer Discharge Simulation Results and Analysis 4.1 The Influence of Humidity on the Average Development Speed of Streamer 4.2 Effect of Humidity on Charged Particle Concentration in Streamer Development Channel 4.3 Effect of Humidity on Electric Field Intensity During Streamer Development 5 Conclusion References Simulation Study on Potential Distribution Characteristics of Backfilling Water in Distribution Room 1 Introduction 2 Human Safety Potential Threshold Under Water Immersion Condition 2.1 Human Current Safety Threshold 2.2 Human Voltage Safety Threshold 3 Simulation Model and Parameters of Water Dispersion in Underground Distribution Room 4 Simulation Calculation of Water Flow Potential Distribution in Distribution Room 4.1 Simulation Calculation of Water Flow Potential Distribution 4.2 Calculation and Analysis of Influencing Factors of Water Charged Potential in Distribution Room 4.3 Conservatory Measure 5 Conclusion References Study on Temperature Rise Characteristics of Tower Grounding Electrode Under Lightning Strike and Power Frequency Short-Circuit Conditions 1 Introduction 1.1 A Subsection Sample 2 Simulation Model and Parameters 3 Lightning and Power Frequency Short Circuit Current Simulation Calculation 3.1 Lightning Strike Current Simulation Calculation 3.2 Power Frequency Short Circuit Current into the Ground Current Simulation Calculation 4 Thermal Stability Calculation of Tower Grounding Electrode 4.1 Temperature Field Distribution Calculation Mathematical Model and Boundary Conditions 4.2 Influence of Grounding Material 4.3 The Influence of Current Amplitude 5 Conclusion References Study on Dissipative Characteristics and Thermal Stability of Typical Grounding Materials in Substation 1 Introduction 2 Simulation Models and Parameters 2.1 Dynamic and Thermal Stability of the Grounding Body 2.2 Substation Intrusion Lightning Current Waveform and Parameters 2.3 Power Frequency Short-Circuit Current and Parameters 2.4 Substation Grounding Network Simulation Model and Parameters 3 Ground Dispersion and Thermal Stability Analysis Under the Action of Intrusion Lightning Current 3.1 The Effect of the Amplitude of the Lightning Current 3.2 Influence of Soil Parameters 3.3 The Effect of the Current Entering the Location 4 Simulation Analysis of Thermal Stability Under Power Frequency Short Circuit 4.1 The Effect of Short-Circuit Current Amplitude 4.2 The Effect of the Current Entering the Location 5 Conclusion References Study on Mechanism and Protection of Lightning Overvoltage of Anticorrosive Layer of Buried Oil and Gas Pipeline Adjacent to Power Line 1 Introduction 2 Lightning Scattering Process of Pipeline Adjacent Power Line 3 Pipeline Overvo