永磁直驱电机设计

1、Axial Flux Permanent Magnet Brushless MachinesAxial Flux Permanent MagnetBrushless MachinesbyJACEK F. GIERASUnited Technologies Research Center,East Hartford, Connecticut, U.S.A.RONG-JIE WANGUniversity of Stellenbosch,Stellenbosch, Western Cape, South AfricaandMAARTEN J. KAMPERUniversity of Stellenb

2、osch,Stellenbosch, Western Cape, South AfricaKLUWER ACADEMIC PUBLISHERSNEW YORK, BOSTON, DORDRECHT, LONDON, MOSCOWeBook ISBN:1-4020-2720-6Print ISBN:1-4020-2661-7?2005 Springer Science + Business Media, Inc.Print ?2004 Kluwer Academic PublishersDordrechtAll rights reservedelectronic,No part of this

3、eBook may be reproduced or transmitted in any form or by any means, mechanical, recording, or otherwise, without written consent from the PublisherCreated in the United States of AmericaVisit Springer's eBookstore at: and the Springer Global Website Online at:ContentsPrefacexi1. INTRODUCTION11.1

4、 Scope11.2 Features11.3 Development of AFPM machines31.4 Types of axial flux PM machines41.5 Topologies and geometries61.6 Axial magnetic field excited by PMs101.7 PM eddy-current brake as the simplest AFPMbrushless machine131.8 AFPM machines versus RFPM machines161.9 Power limitation of AFPM machin

5、es19Numerical examples192. PRI NCI PLES OF AFPM MACHINES272.1 Magnetic circuits272.1.1 Single-sided machines272.1.2 Double-sided machines with internal PM disc rotor272.1.3 Double-sided machines with internal ring-shapedcore stator292.1.4 Double-sided machines with internal slotted stator312.1.5 Dou

6、ble-sided machines with internal coreless stator322.1.6 Multidisc machines322.2 Windings332.2.1 Three-phase windings distributed in slots33Drum-type winding35Contentsix2.2.2 Coreless stator winding352.2.3 Salient pole windings372.3 Torque production372.4 Magnetic flux392.5 Electromagnetic torque and

7、 EMF402.6 Losses and efficiency422.6.1 Stator winding losses422.6.2 Stator core losses442.6.3 Core loss finite element model452.6.4 Losses in permanent magnets452.6.5 Rotor core losses472.6.6 Eddy current losses in stator conductors482.6.7 Rotational losses492.6.8 Losses for nonsinusoidal current502

8、.6.9 Efficiency502.7 Phasor diagrams512.8 Sizing equations542.9 Armature reaction572.10 AFPM motor612.10.1 Sine-wave motor612.10.2 Square-wave motor622.11 AFPM synchronous generator652.11.1 Performance characteristics of a stand alonegenerator652.11.2 Synchronization with utility grid66Numerical exa

9、mples683. MATERIALS AND FABRICATION793.1 Stator cores793.1.1 Nonoriented electrical steels793.1.2 Amorphous ferromagnetic alloys833.1.3 Soft magnetic powder composites843.1.4 Fabrication of stator cores873.2 Rotor magnetic circuits903.2.1 PM materials903.2.2 Characteristics of PM materials953.2.3 Op

10、erating diagram993.2.4 Permeances for main and leakage fluxes1033.2.5 Calculation of magnetic circuits with PMs1073.2.6 Fabrication of rotor magnetic circuits1093.3 Windings1123.3.1 Conductors1123.3.2 Fabrication of slotted windings1123.3.3 Fabrication of coreless windings114Numerical examples1164.

11、AFPM MACHINES WITH IRON CORES1254.1 Geometries1254.2 Commercial AFPM machines with stator ferromagnetic cores 1264.3 Some features of iron-cored AFPM machines1274.4 Magnetic flux density distribution in the air gap1284.5 Calculation of reactances1304.5.1 Synchronous and armature reaction reactances1

12、304.5.2 Stator leakage reactance1314.6 Performance characteristics1344.7 Performance calculation1364.7.1 Sine-wave AFPM machine1364.7.2 Synchronous generator1384.7.3 Square-wave AFPM machine1414.8 Finite element calculations141Numerical examples1445. AFPM MACHINES WITHOUT STATOR CORES1535.1 Advantag

13、es and disadvantages1535.2 Commercial coreless stator AFPM machines1535.3 Performance calculation1555.3.1 Steady-state performance1555.3.2 Dynamic performance1575.4 Calculation of coreless winding inductances1595.4.1 Classical approach1595.4.2 FEM approach1605.5 Performance characteristics1625.6 Edd

14、y current losses in the stator windings1635.6.1 Eddy current loss resistance1635.6.2 Reduction of eddy current losses1675.6.3 Reduction of circulating current losses1685.6.4 Measurement of eddy current losses1705.7 Armature Reaction1705.8 Mechanical design features1735.8.1 Mechanical strength analys

15、is1745.8.2 Imbalanced axial force on the stator1775.9 Thermal problems179Numerical examples 1796. AFPM MACHINES WITHOUT STATOR AND ROTOR CORES1896.1 Advantages and disadvantages1896.2 Topology and construction1896.3 Air gap magnetic flux density1926.4 Electromagnetic torque and EMF1936.5 Commercial

16、coreless AFPM motors1946.6 Case study: low-speed AFPM coreless brushless motor1976.6.1 Performance characteristics1976.6.2 Cost analysis1986.6.3 Comparison with cylindrical motor with laminatedstator and rotor cores1996.7 Case study: low-speed coreless AFPM brushless generator2006.8 Characteristics

17、of coreless AFPM machines201Numerical examples2047. CONTROL2137.1 Control of trapezoidal AFPM machine2137.1.1 Voltage equations2147.1.2 Solid-state converter2167.1.3 Current control2197.1.4 Speed control2227.1.5 High speed operation2227.2 Control of sinusoidal AFPM machine2237.2.1 Mathematical model

18、 and dq equivalent circuits2247.2.2 Current control2297.2.3 Speed control2307.2.4 Hardware of sinusoidal AFPM machine drive2347.3 Sensorless position control237Numerical examples2398. COOLING AND HEAT TRANSFER2498.1 Importance of thermal analysis2498.2 Heat transfer modes2498.2.1 Conduction2508.2.2

19、Radiation2508.2.3 Convection2518.3 Cooling of AFPM machines2558.3.1 AFPM machines with self-ventilation2558.3.2 AFPM machines with external ventilation2648.4 Lumped parameter thermal model2678.4.1 Thermal equivalent circuit2688.4.2 Conservation of energy2698.5 Machine duties2708.5.1 Continuous duty2

20、708.5.2 Short-time duty2718.5.3 Intermittent duty272Numerical examples2729. APPLICATIONS2819.1 Power generation2819.1.1 High speed generators2819.1.2 Low speed generators2829.2 Electric vehicles2859.2.1 Hybrid electric vehicles2879.2.2 Battery electric vehicles2899.3 Ship propulsion2919.3.1 Large AF

21、PM motors2919.3.2 Propulsion of unmanned submarines2929.3.3 Counterrotating rotor marine propulsion system2929.4 Electromagnetic aircraft launch system2959.5 Mobile drill rigs2979.6 Elevators2999.7 Miniature AFPM brushless motors3029.8 Vibration motors3049.9 Computer hard disc drives306Numerical exa

22、mples 307Contents#Contents#Symbols and Abbreviations311References321Index337PrefaceThe drop in prices of rare-earth permanent magnet (PM) materials and progress in power electronics have played an important role in the development of PM brushless machines in the last three decadesT.hese machines hav

23、e recently become mature and their high efficiency, power density and reliability has led to PM brushless machines successfully replacing d.c. commutator machines and cage induction machines in many areas.The axial flux PM (AFPM) brushless machine, also called the disc-type machine, is an attractive

24、 alternative to its cylindrical radial flux counterpart due to the pancake shape, compact construction and high torque density.AFPM motors are particularly suitable for electrical vehicles, pumps, valve control, centrifuges, fans, machine tools, hoists, robots and manufacturing. They have become widely used for low-torque servo and speed control systems. The application of AFPM machines as generators is justified in wind turbines, portable generator