Multiple 3-phase Fault Tolerant Permanent Magnet Machine Drives

Bo Wang, PhD, is an Associate Research Fellow and PhD supervisor at the School of Electrical Engineering at Southeast University, China. He has published over 50+ papers in SCI/EI cited journals and conferences, and he serves as reviewer for top SCI journals and international conferences. He is also a Senior IEEE Member. Jiabin Wang, PhD, is an Emeritus Professor with the Electrical Machines and Drives Group at the University of Sheffield, United Kingdom. To date, he has published 180 definitive papers in leading international journals in print and in press, and 250 papers in refereed international conference proceedings.

• About the Authors xiiiPreface xv1 Introduction to Fault-Tolerant Machine Drives 11.1 Background of Fault-Tolerant Machine Drives 11.2 Frequent Faults in Electric Drives 21.3 Design Requirements of Fault-Tolerant Machine Drives 41.4 Current State-of-the-Art Techniques of Fault-Tolerant Machine Drives 51.4.1 Fault-Tolerant Machine Drive Topologies 61.4.2 Fault Modeling Techniques 121.4.3 Fault Detection Techniques 141.4.4 Postfault Control Strategies 171.5 Scope and Outline of This Book 201.5.1 Scope of this Book 201.5.2 Outline of this Book 20References 222 Multiple 3-Phase Fault-Tolerant Machine Drive with Segregated Windings 332.1 Introduction 332.2 PMA-SynRM with Segregated Windings 352.3 Fault-Tolerant Capability Assessment 382.3.1 Healthy Operation 382.3.2 One 3-Phase Set Open Circuit 412.3.3 One 3-Phase Set Short Circuit 442.3.4 Intraphase Turn Fault 462.3.5 Interphase Turn Fault 512.3.6 Phase-to-Ground Fault 542.3.7 Uncontrolled Rectification Fault 572.3.8 Demagnetization Fault 582.3.9 dc Link Capacitor Fault 592.4 Analysis of Fault Operation Behavior 612.4.1 Analysis of Machine Winding MMF 612.4.2 Analysis of Open-Circuit Fault 652.4.3 Analysis of Short-Circuit Fault 702.5 Summary 73References 743 Design Optimization of Multiple 3-Phase Fault-Tolerant Machine 773.1 Introduction 773.2 Design Specifications 783.3 Design Optimization Process 793.3.1 Optimization Tools 803.3.2 Flux Linkage Machine Model Based on FE Computation 823.3.3 Full Model Integration for Interturn Fault Current Prediction 823.3.4 Cooling Design 853.3.5 Lumped Parameter Thermal Model 873.3.6 Optimization Objective, Constraints, and Parameters 893.4 Selected Design Alternatives and Performance Comparison 923.5 Test Setup of Fault-Tolerant Machine Drives 953.6 Test Under Healthy Conditions 983.6.1 No-Load Test 983.6.2 On-Load Test 1013.6.3 Thermal Test in Healthy Condition 1053.7 Test Under Fault Conditions 1073.7.1 Test Under One 3-Phase Set in Open Circuit 1073.7.2 Test Under One 3-Phase Set in Short Circuit 1093.7.3 Interturn Short-Circuit Test 1103.7.4 Thermal Test Under Turn Fault Condition with TSC 1143.8 Summary 116References 1164 General Modeling Technique for Multiple 3-Phase Machine Drive 1194.1 Introduction 1194.2 General Modeling Technique for 3-Phase Winding Sets 1214.2.1 MMF Analysis for 3-Phase Winding Sets 1214.2.2 General Modeling Approach 1244.2.3 4D Table Construction 1254.2.4 Model Integration with Voltage Equations 1274.3 Study on Model Accuracy and Computational Efficiency 1294.3.1 Healthy Operation 1294.3.2 Open Circuit 1304.3.3 Short Circuit 1324.3.4 Unbalanced Current Operation 1354.3.5 Influence of Phase Resistances on Model Accuracy 1364.4 General Modeling of Turn Fault 1404.4.1 Turn Fault Description 1404.4.2 Equivalent Input for the General Model Under a Turn Fault 1404.4.3 Flux Linkage of Fault Turn 1424.4.4 Voltage Equations 1474.5 Study on Model Accuracy and Computational Efficiency Under Turn Fault 1484.5.1 Turn Fault Behaviors Without Terminal Short Circuit 1494.5.2 Turn Fault Behaviors with Terminal Short Circuit 1524.6 Model Validation by Experimental Tests 1554.6.1 Healthy Condition 1554.6.2 One-Set Open Circuit 1574.6.3 One-Set Short Circuit 1574.6.4 Unbalanced Current Operation 1604.6.5 Turn Fault Without Terminal Short Circuit 1614.6.6 Turn Fault with Terminal Short Circuit 1644.7 Summary 168References 1695 Fault Detection Techniques for the Multiple 3-Phase Machine Drive 1715.1 Introduction 1715.2 Analysis of Fault Signal Under Open Circuit of an Inverter Switch 1735.2.1 Inverter Switching Function Definition 1745.2.2 Characteristics of Inverter Arm Mid-Point Voltages 1745.2.3 Output Voltage Vector Analysis Under Fault Conditions 1755.3 Open-Circuit Fault Detection Design 1815.4 Experimental Validation on Open-Circuit Fault Detection 1835.4.1 Single Switch Fault Diagnosis 1845.4.2 Influence of Load Transients on the Detection Scheme 1855.4.3 Detection with Parameter Variation 1875.4.4 Fault Mitigation Test After Open-Circuit Fault 1875.5 Analysis of Turn Fault Signature 1895.6 Turn Fault Detection Design 1935.7 Experimental Validation on Turn Fault Detection 1965.7.1 Typical Turn Fault Behavior 1965.7.2 Detectability over the Wide Operating Region 1985.7.3 Effect of Transient Conditions on Detection 2015.7.4 Fault Mitigation Test 2035.8 High-Frequency Signal-Based Turn Fault Detection Techniques 2055.9 Summary 208References 2086 Postfault Control Strategies for Fault-Tolerant Machine Drives 2136.1 Introduction 2136.2 Postfault Optimal Torque Control Strategies for Multiphase FSCW PM Machines 2156.3 Simulation Validation on the Optimal Torque Control Strategy 2196.3.1 Optimal Torque Control in the Constant Torque Region 2206.3.2 Optimal Torque Control in the Constant Power Region 2226.4 Turn Fault Mitigation by Current Injection 2246.4.1 Flux Linkage by Rotor PM Field 2256.4.2 Flux Linkage by the Currents in Healthy Sets 2256.4.3 Flux Linkage by the Currents in Fault Set 2276.4.4 Total Flux Linkage in Fault Phase 2286.5 Simulation Validation on the Current Injection Technique 2296.5.1 Effectiveness of Current Injection 2306.5.2 Residual Flux Linkage of the Fault Turns 2336.5.3 Influence of the Slot Position of Fault Turns 2356.5.4 Influence of the Number of Faulted Turns 2366.5.5 Influence of Output Torque 2376.5.6 Effectiveness at High Speed 2396.6 Experimental Validation on the Current Injection Technique 2406.6.1 Turn Fault in Coil B 2 2406.6.2 Turn Fault in Coil A 1 2446.6.3 Integrated Fault Test with Current Injection 2466.7 Summary 246References 2487 Novel Segregated Windings with Enhanced Fault Tolerance for Multiple 3-Phase Machine 2517.1 Introduction 2517.2 Multiple 3-Phase Machines with Four Alternative Segregated Windings 2537.2.1 Zero-Sequence Flux Linkage in Star-Connected Windings 2537.2.2 Delta-Connected Winding Configuration 2567.2.3 Star-Delta Winding Configuration 2577.2.4 Mixed-Pitch Winding 2587.2.5 Concentric Winding 2627.3 FE Analysis of Machines with Five Segregated Winding Configurations 2647.3.1 Healthy Performance Evaluation 2657.3.2 Open-Circuit Fault 2677.3.3 Short-Circuit Fault 2687.3.4 Single-Turn Short-Circuit Fault 2697.4 Experimental Assessments of Machines with Five Segregated Winding Configurations 2807.4.1 No-Load Test 2817.4.2 Load Test Under Healthy Condition 2837.4.3 Load Test with Open Circuit in One 3-Phase Set 2857.4.4 Load Test with Short Circuit in One 3-Phase Set 2867.4.5 Single-Turn Short-Circuit Test 2907.5 Summary 293References 294Index 297