Hybrid Excited Synchronous Machines: Topologies, Design and Analysis

Our transition towards a cleaner and more sustainable future has seen an increase in the use of electrical energy in the functioning of our society. This implies the need to develop tools and methods which allow us to study electromagnetic devices and ensure their functioning for as long as possible. This requires us to use these tools to understand their behavior, not just as one component, but also in the entire systems in which they can be found, throughout their life cycle. This book provides electrical engineering students and researchers with the resources to analyze how synchronous machines behave over their entire field of operation, particularly focusing on hybrid excited synchronous machines (HESMs). The field of HESMs, although not a fundamental problem in the strict sense of the term, provides answers to a range of fundamental problems: the flux weakening of permanent magnet machines, energy optimization, and lastly the increasing costs of rare-earths permanent magnets.

Table of Contents:
Foreword vii Introduction ix Chapter 1 Hybrid Excited Synchronous Machines: Principles and Structures 1 1.1 Introduction 1 1.2 Interest in hybrid excitation 3 1.2.1 Motoring mode operation 4 1.2.2 Generation mode operation 10 1.3 Hybrid excited structures 12 1.3.1 Classification criteria 13 1.3.2 Structures and classification 19 1.4 Conclusions and perspectives 28 Chapter 2 Control of Hybrid Excited Synchronous Machines 31 2.1 Introduction 31 2.2 Modeling of hybrid excited synchronous machines 32 2.2.1 The nature of the equations 35 2.2.2 Control modes 39 2.3 Torque characteristics and basic control laws 41 2.3.1 Torque characteristics as a function of I and ψ 42 2.3.2 Torque characteristics as a function of V and δ 44 2.3.3 Notion of stability for an open loop and the consequences of closed-loop operations 45 2.3.4 Fundamental control laws 51 2.3.5 Temporary overloaded motor operation 56 2.4 Setting the speed of HESMs (maximal characteristics/envelopes) 58 2.4.1 Low-speed operations 59 2.4.2 Operation at high speeds/the notion of flux weakening 72 2.5 Operations on the entire “torque/speed” plane 111 2.5.1 Efficiency optimization algorithms on the entire “torque/speed” plane 113 2.5.2 Normalized model with losses and the calculation of V n max 118 2.5.3 Machines with non-salient poles (ρ = 1) 121 2.5.4 Machines with salient poles (ρ ≠ 1) 125 2.5.5 Validity of the tools developed and the contribution towards hybrid excitation 131 2.6 Conclusions and perspectives 148 Chapter 3 Experimental Studies of Hybrid Excited Synchronous Machines 153 3.1 Introduction 153 3.2 Machine 1 154 3.2.1 Structure and operating principles 155 3.2.2 Construction 159 3.2.3 Experimental study 162 3.3 Machine 2 170 3.3.1 Structure and operating principle 172 3.3.2 Construction 179 3.3.3 Experimental study 186 3.4 Conclusions and perspectives 194 Conclusion 197 References 199 Index 211

About the Author :
Yacine Amara is Professor of Electrical Engineering at Le Havre Normandy University, France. He started working on the analysis and design of hybrid excited synchronous machines during his PhD thesis more than twenty years ago. Hamid Ben Ahmed is Associate Professor of Electrical Engineering at ENS Rennes, France. His research interests include the design, modeling and optimization of novel topologies for electromagnetic actuators and generators, as well as the optimization of renewable energy systems. Mohamed Gabsi is Professor of Electrical Engineering at ENS ParisSaclay, France. His research interests include switched reluctance motors, vibrations and acoustic noise, and permanent magnet machines.