The proceedings of the 16th Annual Conference of China Electrotechnical Society: Volume II (Lecture Notes in Electrical Engineering, 890)

Contents Coupling Analysis of Transient Electromagnetic Field and Temperature Field in Electromagnetic Launch Rail 1 Introduction 2 Theoretical Analysis of Electrothermal Coupling of Railgun 2.1 Electrothermal Coupling Equation 2.2 Source of Thermal Load 3 Simulation Model and Parameters 3.1 Simulation Model 3.2 Relevant Material Parameters and Inputs 4 Temperature Distribution Under Different Driving Currents 4.1 Simulation Results of X-Y Section 4.2 Simulation Results of Y-Z Section 5 Rail Temperature Change During Continuous Launch 6 Conclusion References Theoretical Attempts to Optimize the Geometrical Shape of Simple Electromagnetic Rail Launcher 1 Introduction 2 Inductance Gradient Theory 2.1 High-Frequency Inductance Gradient 2.2 Low-Frequency Inductance Gradient 2.3 Influence of the Tail Section Size on Inductance Gradient 2.4 Influence of Separation on Inductance Gradient 3 Mathematical Model of Launch Load 3.1 Mathematical Model of Forcing on the Launch Load 3.2 Mathematical Model of Launch Load Mass 4 Discussion on the Optimal Separation 4.1 The Optimal Separation at High-Frequency 4.2 The Optimal Separation at Low-Frequency 5 Conclusions References Force Analysis of Armature in Induction Coil Launcher and Design of Double-Layer Armature 1 Introduction 2 Basic Principle 3 Finite Element Model 3.1 Field-Circuit Coupling Analysis Model 3.2 Coupled Analysis of Electromagnetic and Structural Field 4 Armature Design of Different Materials 5 Design and Force Analysis of Double-Layer Armature 5.1 Double-Layer Armature Model 5.2 Double-Layer Armature Design 5.3 Optimization of Double-Layer Armature Thickness 6 Conclusion References Study on Fast Modeling and Simulation of Multistage Electromagnetic Coil Launcher 1 Introduction 2 The Working Principle and Mathematical Model of MECL 3 Fast Modeling Program Design for MECL System 3.1 Finite Element Simulation of Field-Path Coupling in MECL System 3.2 MECL System Parametric Programming Based on MATLAB 4 Simulation Research and Verification of Ten Stage Electromagnetic Coil Launcher System Model 5 Conclusion References The Application of Electromagnetic Coil Launching Technology in Non-war Military Operations AC Machines 1 Principle and Classification of Electromagnetic Coil Launching Technology 1.1 Induction Coil Launching Technology 1.2 Reluctance Coil Launching Technology 2 Key Technology of Electromagnetic Coil Launch 2.1 Launcher Design Technology 2.2 Pulse Power Technology 2.3 Launch Control Technology 2.4 High-Strength Insulation Material Technology 3 Application Field of Electromagnetic Coil Launching Technology in Non-war Military Operations 3.1 Application of Electromagnetic Coil Launching Technology in the Field of Non-lethal Weapons 3.2 Application of Electromagnetic Coil Launching Technology in the Field of Refusal to Riot 3.3 Application of Electromagnetic Coil Launching Technology in the Field of Emergency Rescue 4 Conclusion References Research on Parameters Optimum Design of Levitation Electromagnet Based on Orthogonal Design for EMS Maglev Train 1 Introduction 2 Numerical Model 3 Simulation Results 4 Optimization Design of Levitation System 5 Conclusions References Research on the Formation of Erosion in Electromagnetic Launch 1 Introduction 2 Research Object 3 Simulation 3.1 Distribution of the Armature-rail Contact Pressure Under Preload 3.2 Distribution of the Current at the Beginning of the Launch 4 Experiment 4.1 High Temperature Friction Experiment 4.2 Microstructure Analysis 4.3 Micro-hardness Test 5 Conclusion References Circuit Analysis of Commutation Process of Saddle Secondary Helical Coil Electromagnetic Launcher 1 Introduction 2 Analyze and Simplify the Brush Commutation Process 3 Commutation Process Analysis 3.1 Section D′B: Before Rear Commutation Process Begin 3.2 Section BE′:Rear Commutation Process Begin 3.3 Section E′C: Front Commutation Process Begin 3.4 Section CF′:Rear Commutation Process End 3.5 Section F′B′:Front Commutation Process End 3.6 Result Analysis 4 Experimental Result 5 Conclusion Appendix References Research on Performance Influence of External Circuit Resistance in Synchronize Induction Coil Catapult 1 Introduction 2 System Working Principle 2.1 Working Principle 2.2 Circuit Equation 2.3 Computing Efficiency 3 Simulation Analysis 3.1 Effect of Equivalent Resistance of Discharge Circuit on Emission Performance 3.2 Effect of Equivalent Resistance of Continuous Circuit on Emission Performance 4 Experimental Verification 5 Conclusion References Influence of Copper Wire Sectional Shape on Induction-Coil Catapult Performance 1 Introduction 2 The Design of the Copper Wire of the Driving Coil 2.1 Shape and Size Design of Copper Wire 2.2 Copper Wire Resistance Calculation 3 Simulation Calculation of Copper Wire Windings with Different Cross-Sections 3.1 Calculation Model and Parameters 3.2 Simulation Results 4 Electromagnetic Ejection Test and Finite Element Simulation Verification 5 Conclusion References Effect of Temperature on the Performance of Induction Coil Launcher 1 Introduction 2 Model and Parameters of Single-Stage Induction Coil Launcher 3 Comparison Between Finite Element and Circuit Model Method 4 Influence of Temperature on Launch Characteristics of Coil 4.1 Coil Heat Dissipation Analysis 4.2 Coil Stress Comparison Analysis 5 Conclusion References Research of Mechanical Sensitive Factors of a Electromagnetic Rail Gun Cradle 1 Introduction 2 Mechanical Simulation Model of Electromagnetic Rail Gun Cradle 3 Simulating Calculation 3.1 Changes to the Length Calculation Analysis of the Gun Breech Guide 3.2 Changes to the Analysis of the Calculation of the Material Thickness of the Neck Barrel 3.3 Changes to the Analysis of the Calculation of the Material Thickness of the Cradle Rib Plate 4 Interpretation of Result 5 Conclusion References Research on Nonlinear Servo Speed Identification Based on Two-Stage Electric Cylinder 1 Introduction 1.1 Modeling and Analysis of Vertical Erection Device 1.2 Kinematics Model of Vertical Erection Device 1.3 Basic Theory and Mathematical Model of PMSM 2 Control Strategy of Electric Cylinder Servo System 2.1 PI Control 2.2 Model Reference Adaptive Speed Identification Control 2.3 Definition of Sliding Mode Variable Structure Control 2.4 Rotation Speed Identification by Sliding Mode Observation Method 3 Simulation Results 3.1 Characteristic Simulation Under Step Speed and Load Disturbance 3.2 Simulation of the Motion Characteristics of the Electric Cylinder 3.3 Motion Characteristics Under Actual Working Conditions 4 Conclusion References The Continuous High Precision Measurement Technique of Bore Spacing About Rail-Gun 1 Introduction 2 The Principle of Bore Spacing Measurement 3 System Measurement Error Analysis 3.1 Error Analysis of Measurement Principle 3.2 Analysis of Errors Introduced by System Machining Precision 4 Systematic Error Measurement 5 Prototype Adaptability Verification 6 Engineering Measurement of Bore Spacing 7 Conclusion References Research on Armature Loading Control Accuracy Based on Cloud Model Algorithm 1 Introduction 2 Design of the System 3 Design of the Control System 3.1 Theory of Cloud Model 3.2 Control Strategy of the Cloud Model 3.3 The Propulsive Force Control System 3.4 Software Implementation 4 Experimental Results 5 Summary References Model Predictive Control for Electromagnetic Launcher of UAV 1 Introduction 2 Model Predictive Control Method for Electromagnetic Launcher of UAV 3 Simulation Analysis 4 Conclusion References Research on Control Strategy of the Electromagnetic Launch System for Fixed Wing UAV 1 Introduction 2 Key Control Technology of UAV Electromagnetic Boost Launch System 2.1 Mathematical Model of Linear Motor 2.2 Field-Oriented Control 3 100 kg UAV Electromagnetic Boost Launch System 4 Conclusion References Torque Ripple Suppression Strategy of High-Speed Square Wave Permanent Magnet Motor Based on Direct Torque Control 1 Introduction 2 High-Speed Square Wave PMSM Control System 2.1 Motor Mathematical Model 2.2 Motor DTC Block Diagram 3 Torque Ripple Suppression Strategy for High-Speed Square Wave PMSM 3.1 DTC Without Flux Hysteresis 3.2 Torque Ripple Suppression Strategy 4 Simulation 5 Conclusion References Distribution of Breakdown Positions in Conditioning Progress Between Plane-Plane Electrodes in Vacuum Under Lightning Impulse Voltage 1 Introduction 2 Experimental Setup 3 Experimental Results 4 Simulation 5 Discussion 6 Conclusion References Vulnerability Analysis of Distribution Network Considering the Uncertainty of Source and Load 1 Introduction 2 Analysis of Distribution Network Structure 2.1 Model of DG 2.2 Load Characteristics of Electric Vehicles 3 Distribution Network Node Vulnerability Assessment Index 3.1 Improved Nodal Degree 3.2 Improved Nodal Betweenness 3.3 Load Capacity Vulnerability Index of Distribution Network Nodes Based on FVSI 4 Analysis of Calculation Examples 4.1 Setting of Calculation Case 4.2 Simulation Results 5 Conclusion References A Novel Efficiency-Improved LLC-Buck Isolated Power Processing Circuit 1 Introduction 2 Comparison of BOOST-LLC and LLC-BUCK Topology 2.1 Boost Circuit Design 2.2 Buck Circuit Design 2.3 LLC Circuit Design 2.4 Efficiency Comparison Between Boost-LLC and LLC-Buck 3 Experimental Results 3.1 Steady State Waveform and Analysis 3.2 Dynamic Waveform and Analysis 4 Conclusion References Research on Component Parameter for a Dual-Motor Coaxial Propulsion System Used in an Electric Bus 1 Introduction 2 System Configuration and Modeling 3 Methodology 3.1 Analysis Process 3.2 Dynamic Programming 4 Results and Discussion 4.1 Economic Performance Analysis 4.2 Dynamic Performance Analysis 4.3 Feasible Region Analysis of Dual-Motor Power 5 Conclusion References Influence of Winding Placement on the Motor Copper Losses with High Frequency Power Supply 1 Introduction 2 Copper Losses 3 Finite-Element Modelling 3.1 Conductor Modeling 3.2 Simplified Rotor Model 3.3 One-Slot Model 3.4 Winding Placement 4 Simulation Results 5 Conclusion References The Effect of Temperature on the Distribution Characteristics of Spatial Electric Field in Oil of Oil-Pressboard Insulation Under Impulse Voltage 1 Introduction 2 Electric Field Measuring Platform 2.1 Measurement System Composition 2.2 Kerr Electro-optic Effect for Electric Field Measurement Under Impulse Voltage 2.3 Test Model and Applied Voltage 3 The Effect of Temperature 4 Conclusion References A MTPA Control Strategy for Permanent Magnet/Reluctance Hybrid Rotor Dual-Stator Motor 1 Introduction 2 MTPA Control Principle of PM/RHR-DSM 2.1 PM/RHR-DSM Modeling 2.2 MTPA Control System of PM/RHR-DSM 3 Simulation 4 Conclusion References Interaction Between Atmosphere Pressure Plasma Jet and Substrate with Micro-hole 1 Introduction 2 Model Description 3 Results and Discussion 3.1 Characteristics of Neutral Gas Flow 3.2 Characteristics of Plasma Discharge 4 Conclusions References Simulation and Experiment Analysis of Opening Characteristics for High-Current Fast Switch Based on Double-Acting Mechanism 1 Introduction 2 Working Principle 3 Multi-physical Field Simulation Analysis 3.1 Geometric Model 3.2 Simulation Mathematical Model 3.3 Dynamic Characteristics Simulation and Experimental Analysis 3.4 Parameter Simulation Analysis of Double-Spring Permanent Magnet Operation-Electromagnetic Repulsion Mechanism 4 Conclusion References Reduced-Order and Full-Order Models of the Active-Switched-Capacitor/Inductor Quasi Z-Source Converter in Discontinuous Conduction Mode 1 Introduction 2 Reduced-Order Averaged Models 3 Equivalent Circuit Model 4 Full-Order Averaged Models 5 Experimental Verification 5.1 Steady-State Experiments 5.2 Frequency Responses 6 Conclusion References Small-Signal Modeling and Analysis of the Active-Switched-Capacitor/Inductor Quasi Z-Source Converter Working in Continuous Conduction Mode 1 Introduction 2 DC Steady-Status and AC Small-Signal Equations 3 Equivalent Circuit Mode 4 Small-Signal Models Characteristic Analysis 4.1 Non-minimum Phase Behavior 4.2 Input and Output Impedance Characteristics Analysis 5 Experimental Verification 5.1 Steady-State Experiments 5.2 Frequency Responses 6 Conclusion References A Novel Deep Flux Weakening Control Strategy for IPMSM 1 Introduction 2 Operating Constraint of IPMSM 2.1 Mathematical Model and Working Constraints of PMSM 2.2 Working Characteristics and Analysis of the Out-of-Control Flux Weakening Areas 3 Proposed Flux Weakening Control Strategy 3.1 Approximation of the MTPV Curve 3.2 Design of the Deep Flux Weakening Control Strategy 3.3 Voltage Closed-Loop Feedback q-axis Current Incremental Method 4 Simulation Research 4.1 Speed Response 4.2 Current Trajectory 5 Conclusion References Research on Micro-grid Regulation Strategy Formulation Based on Semi-supervised Learning Neural Network Model 1 Introduction 2 Labelling Classification Algorithm for Microgrid Operating State Based on Semi-supervised Learning 2.1 Tri-training Network Model Construction 2.2 Structure of Classification Model Based on BP Neural Network 2.3 Microgrid Operating State Labeling Classification Algorithm Flow Based on Semi-supervised Learning 3 The Similarity Evaluation Index of the Running State 4 Discussion 4.1 Performance Testing of Similarity Matching Algorithm Model Based on Semi-supervised Learning 4.2 Analysis of Optimization Results and Numerical Examples 5 Conclusion References Day-Ahead PV and EVs Power Forecasting of Distribution Network Based on LSTM 1 Introduction 2 LSTM Prediction Method 2.1 Recurrent Neural Network (RNN) 2.2 LSTM Unit Structure 2.3 Forecasting Model Based on LSTM 3 Calculation Example Results 3.1 Data of EVs and PV 3.2 Day-Ahead EVs and PV Forecasting Based on LSTM 4 Conclusion References Study on the Effect of Thermal Degradation on the Morphology Characteristics of Composite Insulator Mandrel Under Vacuum Condition 1 Introduction 2 Thermal Degradation Test 2.1 Test Samples and Instruments 2.2 Test Process 3 Macroscopic Morphology Analysis 3.1 Surface Color Analysis 3.2 Section Crack Analysis 4 Microscopic Morphology Analysis 4.1 Two-Dimensional Micro-topography Analysis 4.2 Three-Dimensional Micro-topography Analysis 5 Conclusion References Research on Distributed Cross-Bay Busbar Protection Based on Ring Network 1 Introduction 2 Research Content 3 Setting Operation 4 Setting Area Operation 5 Switch Operation 6 Conclusion References A Refined Model of On-Board Electric Power System for Turboprop Regional Aircraft 1 Introduction 2 Modeling Method 2.1 System Architecture 2.2 System Modeling 3 Simulation Results 3.1 Normal Operation Scenario 3.2 Fault Reconstruction Scenarios 4 Conclusions References Study of Voltage and Current Inner Control of Voltage-Controlled Converters in High Permeability Environment 1 Introduction 2 Modeling of Voltage-Controlled Mode Converters 2.1 Basic Structure of Voltage-Controlled Mode Converters 2.2 Control Structure of Voltage-Controlled Mode Converters 2.3 Inner-Loop Modeling of Voltage-Controlled Mode Converters 3 Comparison of Characteristics of the Four Control Schemes 3.1 Comparison of Control Loop Gain 3.2 Comparison of Stability Margin Range 3.3 Comparison of Control Bandwidth 3.4 Comparison of Anti-disturbance Performance 4 Simulation and Experiment Results 4.1 Platform 4.2 Verification of the Effect of Regulators Gain on System Stability 4.3 Verification of Tracking Performance 4.4 Verification of Anti-disturbance Performance 5 Conclusion References Study on the Morphology Change of Acid-Resistant Core Rods of Composite Insulators Under Acid-Heat Condition 1 Introduction 2 Experimental Procedure 2.1 Test Specimen 2.2 Experiment Method 3 Topography Analysis Based on Direct Observation and SEM 3.1 Morphology Analysis of Acid Etching Core Rod 3.2 Analysis of Acid-Heat Deterioration Morphology 3.3 Morphology Analysis of Decay-Like Core Rod 4 Analysis of Three-Dimensional Microscopic Topography Based on CLSM 5 Conclusion References Research on Optimal Dispatching of Multi-region Integrated Energy System Considering Electric Load Price Based Demand Response 1 Introduction 2 Multi-region IES 3 Price-Based Demand Response Model 4 Optimal Dispatch of Multi-region IES Considering Demand Response 4.1 Objective Function 4.2 Constraints 4.3 Problem Solving Method 5 Case Analysis 5.1 Impact of Demand Response on Electrical Load 5.2 Optimal Dispatch of Multi-region IES Considering Electric Load Demand Response 6 Conclusions References A Deep Adversarial Diagnosis Method for Fault Line Detection with Imbalanced Small Sample Scenarios 1 Introduction 2 Fault Line Detection Method 2.1 Data Preprocess 2.2 Data Augmentation 2.3 Feature Extraction and Classification 2.4 Fault Line Detection Process 3 Algorithm Verification 3.1 Simulation Model and Parameters 3.2 Synthetic Signal Visualization 3.3 Adaptivity Analysis 4 Conclusion References Experimental Investigation on Magnetic Field Controlled One-Dimensional Plasma Jet Array in He 1 Background 2 Experimental Equipment and Measurement Method 2.1 Experimental Equipment 2.2 Measurement Method 3 Results and Discussion 3.1 Electrical Characterization 3.2 Optical Characterization 4 Conclusions References Inspection Text Classification of Power Equipment Based on TextCNN 1 Introduction 2 Classification Framework and Data Pre-processing 2.1 Characteristics of Inspection Text 2.2 Pre-processing Process 3 Model Building 3.1 Data Augmentation 3.2 Evaluation Metrics 4 Example Analysis 4.1 Comparison of Different Models 4.2 Effect of Data Augmentation 5 Conclusion References Research on Reactive Power Compensation Site Selection Method for Reducing Commutation Failure Risk of MIDC System 1 Introduction 2 Mechanism Analysis of Commutation Failure 3 Simulation Analysis of Henan Power Grid 4 Reactive Power Compensation Site Selection Optimization Method 4.1 Identify the Voltage Weakness Area of the Receiving Power Grid 4.2 Identify Reactive Power Compensation Sites 5 Simulation Verification 6 Conclusion References Intelligent Power Transmission and Transformation Technology for PIoT 1 Introduction 2 Overview of Smart Grid 3 PIoT Architecture 3.1 Sensing Layer 3.2 Network Layer 3.3 Platform Layer 3.4 Application Layer 4 PIoT Applications 4.1 Substation Applications 4.2 Transmission Line Applications 5 Development Trend of PIoT 6 Conclusion References Study on the Blocking Capability Decreasing of SiC MOSFET After Short-Circuit Gate-Source Failure 1 Introduction 2 Gate-Source Failure Determination Method 2.1 Mechanism of Gate-Source Short-Circuit 2.2 Determination Method of Gate-Source Failure 3 Short-Circuit Experiment 3.1 Short-Circuit Experimental Setup 3.2 Experimental Results 4 Leakage Current Analysis 4.1 Leakage Current Measurement 4.2 Mechanism Analysis of the Increase of Leakage Current 5 Conclusion References A Transmission Line Multi-parameter Monitoring System Based on FBG Sensors 1 Introduction 2 Principle and Sensor Design 2.1 Sensing Principle of FBG 2.2 Design of FBG Anemometer 2.3 Design of FBG Tension Sensor 3 Design of the Sensing System 3.1 Overall System Structure 4 Conclusion References Reconstruction of Open-Circuit Voltage for Aging Lithium-Ion Batteries Based on Big Data 1 Introduction 2 Data Acquisition 2.1 Aging Tests 2.2 OCV Data Cloud Generation 3 Proposed Method 4 Results and Discussions 5 Conclusion References A Switched-Capacitor-Based Multilevel Converter for Photovoltaic Systems Suffering from Power Mismatch 1 Introduction 2 Proposed Multilevel Converter 3 Operation Principle 3.1 The Principle of Voltage Self-balancing 3.2 Control Strategy 3.3 Modulation Strategy 4 Simulation Results 4.1 Case 1: A PV DC Port Interats with the Converter 4.2 Case 2: Two PV DC Ports Interact with the Converter 4.3 Case 3: Three PV DC Ports Interact with the Converter 4.4 Case 4: Four PV DC Ports Interact with the Converter 5 Conclusion References Difficulty Analysis and Test Method Research on Performance Test of Medium Voltage Photovoltaic Power Generation Unit 1 Introduction 2 Difficulties in Performance Test of MV-PGU 3 Research on Test Verification Method 4 Empirical Test Cases 5 Conclusion References Digital Twin System for Service Performance Evaluation of Anti-vibration Device 1 Introduction 2 Modeling of Digital Twin System 3 Experiment 4 Discussion 5 Conclusion References Research on Fiber Channel Message Recording Scheme Based on Data Statistics 1 Introduction 2 Current Status of Fiber Channel Applications 2.1 Fiber Channel Topology 2.2 Problems and Detection Methods During Operation 3 Key Technical Solutions 3.1 Message Collection Unit 3.2 Message Analysis Unit 3.3 Message Statistics Unit 3.4 Message Storage Unit 3.5 Hardware Implementation 4 Test Verification 5 Conclusion References Research on Control Strategy of Energy Storage System to Improve Wind Power Smoothing Ability 1 Preface 2 Wind Power Output Model 2.1 Wind Frequency Characteristics of Wind Power Plant 3 Energy Storage System Model 3.1 Structure of Wind Power Plant Energy Storage System 3.2 Energy Storage System Cost Model 3.3 Constraints of Energy Storage System 4 Optimization of Energy Storage System Configuration Based on Genetic Algorithm 4.1 Basic Principles of Genetic Algorithm 5 Control and Configuration of Energy Storage System Based on Two-Layer Model 5.1 Bilevel Optimization Model 5.2 Example Analysis 6 Conclusion References Analysis and Calculation of the Capacitor Current and Voltage Ripples for Z-Source Inverters 1 Introduction 2 ZSI Capacitor Current and RMS Value 3 Capacitor Voltage Ripple Calculation 4 Experimental Results 5 Conclusion References Feasibility Analysis of Using the Normal Vector to Determine the Most Dangerous Power Increasing Direction of the Small-Signal Stability 1 Introduction 2 Static Voltage Stability Analysis 2.1 Static Voltage Stability Analysis Method 2.2 Difficulties in Solving the MDPID of Small-Signal Stability 3 Boundary Conditions of Small-Signal Stability 3.1 The Mathematical Model of the Power System Small-Signal Stability 3.2 Boundary Conditions 4 Model of the Most Dangerous Power Increasing Direction of Small-Signal Stability 4.1 The Relationship Between the Normal Vector and the MDPID 4.2 Normal Vector Construction and Determination of the MDPID 4.3 The Most Dangerous Power Increasing Direction Model 4.4 Model Solution Analysis 5 Conclusion References Design of Main Wiring Diagram Drawing System of Relay Protection Device 1 Introduction 2 System Architecture 3 Module Design 3.1 System Protocol Module 3.2 System Protocol Module 3.3 Main Wiring Diagram Drawing Module 4 System Application 5 Conclusion References Monitoring and Management Technical Research for Battery Energy Storage 1 Introduction 2 System Architecture 3 Module Design 3.1 BIMU 3.2 BCMU 3.3 BMU 3.4 External Communication Unit 4 System Application 5 Conclusion References Analysis of Lightning Impulse Response of Ground Network Based on a Distributed π Model 1 Introduction 2 Theory of Modeling 3 Simulation and Analysis 3.1 Voltage Transient Characteristics 3.2 Voltage Transient Characteristics 4 Conclusion References High-Resistance Fault Transient Line Selection Method Based on Ground Parameter Identification 1 Introduction 2 Principle of Line Selection for Transient Energy Based on Identification of Ground Parameters 3 Simulation 3.1 Analysis of Partial Results of Line Selection by Transient Energy Method 3.2 Validation of Simulation Line Selection Results 4 Conclusion References Research on MMC Circulation Suppression Strategy Based on Improved Active Disturbance Rejection and Virtual Impedance Composite Control 1 Introduction 2 Topological Structure and Circulation Generation Mechanism of MMC 3 MMC Circulation Suppression Strategy 3.1 Extraction of the Second Harmonic Circulation 3.2 Improved Linear Active Disturbance Rejection Control 3.3 Circulating Current Suppression Controller Design 4 Simulation 5 Conclusion References Simulation and Verification of the Temperature Field of 220 kV Natural Ester Insulating Oil Transformer 1 Introduction 2 Simulation of Temperature Field of Natural Ester Insulating Oil Transformer 2.1 Simulation Model 2.2 Setting of Model Parameters and Boundary Conditions 2.3 Simulation Results 2.4 Comparison of the Influence of Natural Ester Insulating Oil and Mineral Insulating Oil on the Temperature Field Distribution of Windings 3 Comparison of Simulation Results and Test Data 4 Conclusion References Design of AC Air Arc Generator Power Supply 1 Introduction 2 Structure of Power Supply Module 3 Simulation of Rectifier Circuit 4 Boost Circuit 4.1 Boost Circuit Open-Loop Characteristics Analysis 4.2 Boost Open-Loop Circuit Simulation 4.3 Boost Circuit Closed-Loop Control and Simulation 5 Inverter Circuit 5.1 Inverter Circuit Open-Loop Characteristic Analysis 5.2 Open-Loop Simulation of the Inverter Circuit 5.3 Closed-Loop Control and Simulation of the Inverter Circuit 6 Power Module Overall Simulation 7 Conclusion References A Compact Capacitive Power Transfer System Based on Planar Inductors 1 Introduction 2 Circuit Topology 3 Design of Capacitive Coupler 4 Experimental Results 5 Conclusion References Optimization Design of a Novel Partitioned Stator Hybrid Excited Permanent Magnet Vernier Machine with DC-Biased Sinusoidal Current 1 Introduction 2 Basic Principle of Proposed PSHE-PMVM Drive System 2.1 Configuration of Proposed PSHE-PMVM 2.2 Main Drive Circuit 2.3 Operation Principle 3 Simulation and Optimization 4 Conclusion References Image Recognition of Bird Pecking Defects in Composite Insulators Based on Improved HED Network 1 Introduction 2 Image Processing Process 3 Methods 3.1 Image Filtering 3.2 Image Enhancement 3.3 Semantic Segmentation 4 Experimental Results and Analysis 4.1 Experimental Results and Subjective Comparison Analysis of Improved HED Algorithm 4.2 Quantitative Comparative Analysis of Improved HED Algorithm 5 Conclusion References Prediction on the Induced Magnetic Signature of Ships Using Genetic Neural Network 1 Introduction 2 Genetic Neural Network Model 3 Simulation Analysis 3.1 Data Generation 3.2 Simulation Results 3.3 Error Analysis 4 Experimental Results 5 Conclusions References Reduced-Dimensionality Modeling of Azimuthal-Symmetric Structures UnderNon-symmetric Excitation in Electrostatics 1 Introduction 2 Theory and Numerical Methods 2.1 Reduced Dimensional Modeling 2.2 Weak Formulation of the Governing Equation 3 Numerical Results and Discussions 4 Conclusions References Study on Temperature Recognition of Metal Materials by Video Image in Sunlight Environment 1 Introduction 2 Experimental Device and Method 2.1 Experimental Device 2.2 Experimental Method 3 Data Processing 3.1 Reading Image Data 3.2 Extracting Image Features 3.3 Machine Learning 4 Result and Discussion 4.1 Effect of Sunlight Intensity on Training Results 4.2 Influence of Shooting Distance on Training Results 4.3 Training Effect of Model with Wide Range Variation of Sunlight Intensity 4.4 Comparison of Training Results Between Video Images and Mobile Phone Photos 5 Conclusion References Application of Electromagnetic Emission Technology in In-Situ Subsea Dynamic Penetration Test 1 Introduction 1.1 Marine Geological Exploration 1.2 Dynamic Penetration Test 1.3 Electromagnetic Emission Technology 2 Research Method 2.1 Equivalent Design of Electromagnetic Acceleration for DPT 2.2 Single-Stage Electromagnetic Acceleration Design 2.3 Multistage Electromagnetic Acceleration 3 Conclusion References Pressurized Air with Vacuum Breaking is the Best Alternative to SF6 1 Introduction 2 Dielectric Withstand as a Function of Pressure 3 Pressurized Air Tank is Robust 4 Pressurized Air Tank is Safe 5 Leakage Rate of Pressurized Air Tank is Similar to SF6 5.1 Permeation 5.2 Leakages at Interfaces 5.3 Example of Pressure Loss Calculation 6 Internal Arc of Pressurized Air Tank is Similar to SF6 Tank 7 Leakage Detection on Site with Acoustic System 7.1 Nominal No-Leak (0.1% P.A.) Example 7.2 Non-intended Leakage level > 1 10–3 mbarl/s 8 Switchgear Can Be Operated Down to Atmospheric Pressure 9 No Cost to Recover Gas at End of Life 10 Low Cost Impact of Pressurized Air Tank 11 Conclusion References Optimal Operation of Regional Energy Internet Considering Distributed Resource Aggregation 1 Introduction 2 Mathematical Model of Distributed Resource Aggregation and Optimization 2.1 Distributed Resource Aggregation Modeling 2.2 Objective Function 2.3 Constraints 3 Simulation Results and Analysis 3.1 Example Analysis 4 Conclusion References Charging Network Capacity Planning Equipped with Flexible Charging Facilities Considering User Waiting Time 1 Introduction 2 EV User Waiting Time Modeling by Flexible Charging Facilities 2.1 Power Allocation Model of Multi-plie Flexible Charging Facilities 2.2 Charging Waiting Time Model with User Preferences 3 Charging Network Capacity Planning 3.1 Multi-objective Planning Considering User Waiting Time 3.2 Process for Solving the Multi-objective Planning Problem 4 Case Study 4.1 Case Setup 4.2 Result Analysis 5 Conclusion References Active Power Support for Fast Frequency Response: An Economic Perspective 1 Introduction 2 Risk Assessment of Frequency Regulation Uncertainty 2.1 Conditional Value at Risk 2.2 WG Frequency Regulation Risk Cost 2.3 RDR Frequency Regulation Risk Cost 3 Calculation of Frequency Regulation Cost 3.1 Thermal Power Unit 3.2 Wind Generation 3.3 Residential Demand Response 4 Calculation Example Design 4.1 Two Calculation Results of CVaRα 4.2 Offline Optimization Algorithm 4.3 Comparison of Frequency Regulation Costs 5 Conclusion References Hierarchically Coordinated Optimal Schedule for Virtual Power Plant and Distribution Network Under Multiple Uncertainties 1 Introduction 2 Hierarchically Coordinated Schedule Model 2.1 Optimal Dispatch Model of VPP 2.2 Optimal Schedule Model of Distribution Network 3 Solution Method of Stochastic Programming 4 Case Study 5 Conclusion References Mul