Multiple 3-phase Fault Tolerant Permanent Magnet Machine Drives: Design and Control

Groundbreaking analysis of a fully functional fault-tolerant machine drive Electrical machine drives have become an increasingly important component of transportation electrification, including electric vehicles, railway and subway traction, aerospace actuation, and more. This expansion of electrical machine drives into safety-critical areas has driven an increasingly urgent demand for high reliability and strong fault tolerance. Machine drives incorporating a permanent magnet (PM)-assisted synchronous reluctance machine drive with a segregated winding have shown to exhibit notably reduced PM flux and correspondingly enhanced fault tolerance. Multiple 3-Phase Fault Tolerant Permanent Magnet Machine Drives: Design and Control offers one of the first fully integrated accounts of a functional fault-tolerant machine drive. It proposes a segregated winding which can be incorporated into multiple machine topologies without affecting performance and brings together cutting-edge technologies to manage these crucial drives in both healthy and fault conditions. The result is a must-own for engineers and researchers alike. Readers will also find: Advanced modeling techniques for different operation conditions Detailed discussion on topics including fault detection techniques, postfault tolerant control strategies, and many more An authorial team with immense experience in the study of fault-tolerant machine drives Multiple 3-Phase Fault Tolerant Permanent Magnet Machine Drives: Design and Control is ideal for researchers and graduate students in engineering and related industries.

Table of Contents:
About the Authors xiii Preface xv 1 Introduction to Fault-Tolerant Machine Drives 1 1.1 Background of Fault-Tolerant Machine Drives 1 1.2 Frequent Faults in Electric Drives 2 1.3 Design Requirements of Fault-Tolerant Machine Drives 4 1.4 Current State-of-the-Art Techniques of Fault-Tolerant Machine Drives 5 1.4.1 Fault-Tolerant Machine Drive Topologies 6 1.4.2 Fault Modeling Techniques 12 1.4.3 Fault Detection Techniques 14 1.4.4 Postfault Control Strategies 17 1.5 Scope and Outline of This Book 20 1.5.1 Scope of this Book 20 1.5.2 Outline of this Book 20 References 22 2 Multiple 3-Phase Fault-Tolerant Machine Drive with Segregated Windings 33 2.1 Introduction 33 2.2 PMA-SynRM with Segregated Windings 35 2.3 Fault-Tolerant Capability Assessment 38 2.3.1 Healthy Operation 38 2.3.2 One 3-Phase Set Open Circuit 41 2.3.3 One 3-Phase Set Short Circuit 44 2.3.4 Intraphase Turn Fault 46 2.3.5 Interphase Turn Fault 51 2.3.6 Phase-to-Ground Fault 54 2.3.7 Uncontrolled Rectification Fault 57 2.3.8 Demagnetization Fault 58 2.3.9 dc Link Capacitor Fault 59 2.4 Analysis of Fault Operation Behavior 61 2.4.1 Analysis of Machine Winding MMF 61 2.4.2 Analysis of Open-Circuit Fault 65 2.4.3 Analysis of Short-Circuit Fault 70 2.5 Summary 73 References 74 3 Design Optimization of Multiple 3-Phase Fault-Tolerant Machine 77 3.1 Introduction 77 3.2 Design Specifications 78 3.3 Design Optimization Process 79 3.3.1 Optimization Tools 80 3.3.2 Flux Linkage Machine Model Based on FE Computation 82 3.3.3 Full Model Integration for Interturn Fault Current Prediction 82 3.3.4 Cooling Design 85 3.3.5 Lumped Parameter Thermal Model 87 3.3.6 Optimization Objective, Constraints, and Parameters 89 3.4 Selected Design Alternatives and Performance Comparison 92 3.5 Test Setup of Fault-Tolerant Machine Drives 95 3.6 Test Under Healthy Conditions 98 3.6.1 No-Load Test 98 3.6.2 On-Load Test 101 3.6.3 Thermal Test in Healthy Condition 105 3.7 Test Under Fault Conditions 107 3.7.1 Test Under One 3-Phase Set in Open Circuit 107 3.7.2 Test Under One 3-Phase Set in Short Circuit 109 3.7.3 Interturn Short-Circuit Test 110 3.7.4 Thermal Test Under Turn Fault Condition with TSC 114 3.8 Summary 116 References 116 4 General Modeling Technique for Multiple 3-Phase Machine Drive 119 4.1 Introduction 119 4.2 General Modeling Technique for 3-Phase Winding Sets 121 4.2.1 MMF Analysis for 3-Phase Winding Sets 121 4.2.2 General Modeling Approach 124 4.2.3 4D Table Construction 125 4.2.4 Model Integration with Voltage Equations 127 4.3 Study on Model Accuracy and Computational Efficiency 129 4.3.1 Healthy Operation 129 4.3.2 Open Circuit 130 4.3.3 Short Circuit 132 4.3.4 Unbalanced Current Operation 135 4.3.5 Influence of Phase Resistances on Model Accuracy 136 4.4 General Modeling of Turn Fault 140 4.4.1 Turn Fault Description 140 4.4.2 Equivalent Input for the General Model Under a Turn Fault 140 4.4.3 Flux Linkage of Fault Turn 142 4.4.4 Voltage Equations 147 4.5 Study on Model Accuracy and Computational Efficiency Under Turn Fault 148 4.5.1 Turn Fault Behaviors Without Terminal Short Circuit 149 4.5.2 Turn Fault Behaviors with Terminal Short Circuit 152 4.6 Model Validation by Experimental Tests 155 4.6.1 Healthy Condition 155 4.6.2 One-Set Open Circuit 157 4.6.3 One-Set Short Circuit 157 4.6.4 Unbalanced Current Operation 160 4.6.5 Turn Fault Without Terminal Short Circuit 161 4.6.6 Turn Fault with Terminal Short Circuit 164 4.7 Summary 168 References 169 5 Fault Detection Techniques for the Multiple 3-Phase Machine Drive 171 5.1 Introduction 171 5.2 Analysis of Fault Signal Under Open Circuit of an Inverter Switch 173 5.2.1 Inverter Switching Function Definition 174 5.2.2 Characteristics of Inverter Arm Mid-Point Voltages 174 5.2.3 Output Voltage Vector Analysis Under Fault Conditions 175 5.3 Open-Circuit Fault Detection Design 181 5.4 Experimental Validation on Open-Circuit Fault Detection 183 5.4.1 Single Switch Fault Diagnosis 184 5.4.2 Influence of Load Transients on the Detection Scheme 185 5.4.3 Detection with Parameter Variation 187 5.4.4 Fault Mitigation Test After Open-Circuit Fault 187 5.5 Analysis of Turn Fault Signature 189 5.6 Turn Fault Detection Design 193 5.7 Experimental Validation on Turn Fault Detection 196 5.7.1 Typical Turn Fault Behavior 196 5.7.2 Detectability over the Wide Operating Region 198 5.7.3 Effect of Transient Conditions on Detection 201 5.7.4 Fault Mitigation Test 203 5.8 High-Frequency Signal-Based Turn Fault Detection Techniques 205 5.9 Summary 208 References 208 6 Postfault Control Strategies for Fault-Tolerant Machine Drives 213 6.1 Introduction 213 6.2 Postfault Optimal Torque Control Strategies for Multiphase FSCW PM Machines 215 6.3 Simulation Validation on the Optimal Torque Control Strategy 219 6.3.1 Optimal Torque Control in the Constant Torque Region 220 6.3.2 Optimal Torque Control in the Constant Power Region 222 6.4 Turn Fault Mitigation by Current Injection 224 6.4.1 Flux Linkage by Rotor PM Field 225 6.4.2 Flux Linkage by the Currents in Healthy Sets 225 6.4.3 Flux Linkage by the Currents in Fault Set 227 6.4.4 Total Flux Linkage in Fault Phase 228 6.5 Simulation Validation on the Current Injection Technique 229 6.5.1 Effectiveness of Current Injection 230 6.5.2 Residual Flux Linkage of the Fault Turns 233 6.5.3 Influence of the Slot Position of Fault Turns 235 6.5.4 Influence of the Number of Faulted Turns 236 6.5.5 Influence of Output Torque 237 6.5.6 Effectiveness at High Speed 239 6.6 Experimental Validation on the Current Injection Technique 240 6.6.1 Turn Fault in Coil B 2 240 6.6.2 Turn Fault in Coil A 1 244 6.6.3 Integrated Fault Test with Current Injection 246 6.7 Summary 246 References 248 7 Novel Segregated Windings with Enhanced Fault Tolerance for Multiple 3-Phase Machine 251 7.1 Introduction 251 7.2 Multiple 3-Phase Machines with Four Alternative Segregated Windings 253 7.2.1 Zero-Sequence Flux Linkage in Star-Connected Windings 253 7.2.2 Delta-Connected Winding Configuration 256 7.2.3 Star-Delta Winding Configuration 257 7.2.4 Mixed-Pitch Winding 258 7.2.5 Concentric Winding 262 7.3 FE Analysis of Machines with Five Segregated Winding Configurations 264 7.3.1 Healthy Performance Evaluation 265 7.3.2 Open-Circuit Fault 267 7.3.3 Short-Circuit Fault 268 7.3.4 Single-Turn Short-Circuit Fault 269 7.4 Experimental Assessments of Machines with Five Segregated Winding Configurations 280 7.4.1 No-Load Test 281 7.4.2 Load Test Under Healthy Condition 283 7.4.3 Load Test with Open Circuit in One 3-Phase Set 285 7.4.4 Load Test with Short Circuit in One 3-Phase Set 286 7.4.5 Single-Turn Short-Circuit Test 290 7.5 Summary 293 References 294 Index 297