Overview of Permanent-Magnet Brushless Drives for Electric and Hybrid Electric Vehicles
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paper_title: Hybridization of energy sources in electric vehicles

paper_content:

At the present status of electric vehicle (EV) technologies, none of the available energy sources can solely fulfill all the demands of EVs to enable them to compete with gasoline powered vehicles. In this paper, an energy management system, adopting the so-called hybridization of energy sources, is proposed to coordinate multiple energy sources for EVs. Hence, the unique advantages of various EV energy sources can be fully utilized, leading to optimized fuel economy while fulfilling the expected driving range and maintaining other EV performances. The proposed optimization is performed by tuning two ratios, namely the mass ratio and the hybridization ratio.
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paper_title: Novel permanent magnet motor drives for electric vehicles

paper_content:

Novel permanent magnet (PM) motor drives have been successfully developed to fulfil the special requirements for electric vehicles such as high power density, high efficiency, high starting torque, and high cruising speed. These PM motors are all brushless and consist of various types, namely rectangular-fed, sinusoidal-fed, surface-magnet, buried-magnet, and hybrid. The advent of novel motor configurations lies on the unique electromagnetic topology, including the concept of multipole magnetic circuit and full slot-pitch coil span arrangements, leading to a reduction in both magnetic yoke and copper, decoupling of each phase flux path, and hence an increase in both power density and efficiency. Moreover, with the use of fractional number of slots per pole per phase, the cogging torque can be eliminated. On the other hand, by employing the claw-type rotor structure and fixing an additional field winding as the inner stator, these PM hybrid motors can further provide excellent controllability and improve efficiency map. In the PM motors, by purposely making use of the transformer EMF to prevent the current regulator from saturation, a novel control approach is developed to allow for attaining high-speed constant-power operation which is particularly essential for electric vehicles during cruising. Their design philosophy, control strategy, theoretical analysis, computer simulation, experimental tests and application to electric vehicles are described.
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paper_title: Modern Electric Vehicle Technology

paper_content:

1. Engineering Philosophy of EV Developments 2. EV and HEV Developments 3. EV Systems 4. HEV Systems 5. Electric Propulsion 6. Energy Sources 7. EV Auxiliaries 8. EV Simulation 9. EV Infrastructure 10. Energy, environment and economy
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paper_title: Emerging Energy-Efficient Technologies for Hybrid Electric Vehicles

paper_content:

With ever-increasing oil prices, there is fast growing interest in hybrid electric vehicles (HEVs) globally. Thus, it is a pressing need for researchers to develop emerging energy-efficient devices for various kinds of HEVs, including the micro hybrids, mild hybrids, and full hybrids. In this paper, three key emerging energy-efficient technologies are identified and discussed: 1) the thermoelectric waste-heat recovery and temperature control systems for all hybrids, especially micro hybrids; 2) the integrated-starter-generator for mild hybrids; and 3) the electronic continuously variable transmission propulsion for full hybrids.
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paper_title: Novel motors and controllers for high-performance electric vehicle with four in-wheel motors

paper_content:

We have, in accordance with new concepts, undertaken the development of a high-performance electric motor vehicle, designated as the IZA. The main performance features of the IZA are a maximum speed of 176 km/h, a range of 548 km per charge at a constant speed of 30 km/h, and acceleration from 0 to 400 m in 18 s. We have developed a direct driving in-wheel motor and controller in order to achieve high performance characteristics. The in-wheel motor is composed of an outer rotor with a rare earth permanent magnet (Sm-Co) and an inner stator. The motor drive controller consists of a three-phase inverter and a microprocessor-based controller. The maximum output and maximum torque of each total drive system, including motor and inverter, are 25 kW and 42.5 kg/spl middot/m, respectively, and the total efficiency of the drive system is over 90% at the rated speed. The performance of the motor, controller, and drive system have been confirmed by numerous simplex and vehicle transit tests. This paper describes the design concepts, configuration, and performance of the motor, controller, and drive system developed for this high-performance electric vehicle.
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paper_title: An overview of power electronics in electric vehicles

paper_content:

In response to concerns about energy cost, energy dependence, and environmental damage, a rekindling of interest in electric vehicles (EVs) has been obvious. Based on the "California rules" on zero emission vehicles in the United States, as well as similar tightened air pollution regulation in Europe, Asia, and much of the rest of the world, the market size of EVs will be enormous. Thus, the development of power electronics technology for EVs will take an accelerated pace to fulfil the market needs. This paper reviews the current status of multidisciplinary technologies in EVs. Various challenges of power electronics technology for EV propulsion, battery charging, and power accessories are explored.
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paper_title: Design characteristics of the induction motor used for hybrid electric vehicle

paper_content:

Design characteristics of the induction motor used for hybrid electric vehicle (HEV) are discussed. Equivalent circuits corresponding to the starting, operating performance, and harmonics are given. The selecting rules of the starting voltage and frequency are got. The relations between the iron core and copper loss versus frequency are analyzed and compared. The influence of harmonics on the induction motor is analyzed. The design principles of the induction motor used for HEV are given considering the impacts of the starting, operating performance, and harmonics.
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paper_title: A novel sliding-mode observer for indirect position sensing of switched reluctance motor drives

paper_content:

A switched reluctance motor (SRM) drive generally requires a rotor position sensor for commutation and current control. However, the use of this position sensor increases both cost and size of the motor drive and causes limitations for industrial applications. In this paper, a novel indirect position sensing technique, namely, the sliding-mode observer, is proposed for SRM drives. The corresponding design approach and operating performance are provided to illustrate the fast convergence and high robustness of the observer against disturbances and variations.
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paper_title: Spectral analysis of a new six-phase pole-changing induction motor drive for electric vehicles

paper_content:

In this paper, a new six-phase pole-changing induction motor drive is proposed to extend the constant-power operating range for electric vehicle application. The double Fourier series is newly employed to analyze the spectra of the motor phase voltage and current. Consequently, the harmonic expression of the inverter DC-link current can be derived. In order to reduce the DC-link harmonics, a new sinusoidal pulsewidth-modulation strategy is developed for the proposed six-phase inverter. Experimental results, particularly the spectra of the phase current and the DC-link current, are given to verify the theoretical analysis.
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paper_title: Control of switched reluctance drives for electric vehicle applications

paper_content:

Dynamic controllers of switched reluctance drives adjust at least three variables, i.e., current amplitude, turn-on, and turn-off angles. In electric vehicle (EV) applications high efficiency of the drive over a wide speed range, wide torque bandwidth, and low torque ripple under varying DC-bus voltage conditions are important design goals. Hence, controllers of switched reluctance drives for EVs usually have a complex structure. In this paper, the demands on control accuracy of switched reluctance machine traction drives and the traction controller sampling frequency, which are necessary to take advantage of the switched reluctance machine dynamic capabilities, are discussed. To integrate the traction drive, the control commands need to be actualized with a sampling frequency of at least 100 Hz to meet the high-dynamic requirements of modern vehicle control systems, e.g., active cruise control, antislip control, and active damping of mechanical drivetrain oscillations. It is found that the switching angles have to be adjusted within one-tenth of a mechanical degree. This study shows that switched reluctance drives can fulfill all requirements needed for electric propulsion using standard microcontrollers or digital signal processors.
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paper_title: Advantages of switched reluctance motor applications to EV and HEV: design and control issues

paper_content:

Land vehicles need their drivetrain to operate entirely in constant power in order to meet their operational constraints, such as initial acceleration and gradability, with minimum power rating. The internal combustion engine (ICE) is inappropriate for producing this torque-speed profile. Therefore, multiple gear transmission is necessary with the ICE in a vehicle. Some electric machines, if designed and controlled appropriately, are capable of producing an extended constant power range. The purpose of this paper is to investigate the capabilities of the switched reluctance motor (SRM) for electric vehicle and hybrid electric vehicle applications. This investigation is carried out in two steps. The first step involves the machine design and the finite-element analysis to obtain the static characteristic of the motor. In the second step, the finite-element field solutions are used in the development of a nonlinear model to investigate the dynamic performance of the designed motor.
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paper_title: A new surface-inset, permanent-magnet, brushless DC motor drive for electric vehicles

paper_content:

A new five-phase, surface-inset, permanent-magnet (PM), brushless DC motor drive is proposed in this paper. The motor drive has advantages of both the PM brushless DC motor drive and the DC series motor drive. The originality is that the air-gap flux of the motor is generated by both the PM excitation and the specially controlled stator currents (two particular phases) under the same PM pole. The motor configuration and principle of operation are so unusual that the magnetic field distribution and steady-state performance are analyzed by the finite-element method. Experimental results for a prototype verify that the proposed motor drive is promising for modern electric vehicle applications.
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paper_title: Effectiveness of active noise and vibration cancellation for switched reluctance machines operating under alternative control strategies

paper_content:

The effectiveness of active vibration cancellation by inducing antiphase vibration of the stator to reduce the acoustic noise emitted from a switched reluctance machine is evaluated under typical operating modes, viz., single pulse excitation, pulsewidth modulation (PWM) voltage control, and PWM current control. Measurements in both the frequency and time domains are complemented by sound pressure level measurements. It is shown that active vibration cancellation is most effective in reducing a single mode of vibration when a switched reluctance (SR) machine is operated under single-pulse excitation, and becomes less effective when more than one dominant vibration mode exists within the audible frequency range. In general, it also works relatively well when the machine is operated under fixed frequency PWM voltage control, although less effectively than for single pulse control. Further, it is shown that the technique is ineffective when the machine is operated under PWM current control since the duration of the zero voltage period varies significantly from the optimal value due to the random nature of the PWM.
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paper_title: Electrical Machines and Drives for Electric, Hybrid, and Fuel Cell Vehicles

paper_content:

This paper reviews the relative merits of induction, switched reluctance, and permanent-magnet (PM) brushless machines and drives for application in electric, hybrid, and fuel cellvehicles,withparticularemphasisonPMbrushlessmachines. The basic operational characteristics and design requirements, viz. a high torque/power density, high efficiency over a wide operatingrange,andahighmaximumspeedcapability,aswell as the latest developments, are described. Permanent-magnet brushless dc and ac machines and drives are compared in terms of their constant torque and constant power capabilities, and various PM machine topologies and their performance are reviewed. Finally, methods for enhancing the PM excitation torque and reluctance torque components and, thereby, improv- ing the torque and power capability, are described.
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paper_title: A new surface-inset, permanent-magnet, brushless DC motor drive for electric vehicles

paper_content:

A new five-phase, surface-inset, permanent-magnet (PM), brushless DC motor drive is proposed in this paper. The motor drive has advantages of both the PM brushless DC motor drive and the DC series motor drive. The originality is that the air-gap flux of the motor is generated by both the PM excitation and the specially controlled stator currents (two particular phases) under the same PM pole. The motor configuration and principle of operation are so unusual that the magnetic field distribution and steady-state performance are analyzed by the finite-element method. Experimental results for a prototype verify that the proposed motor drive is promising for modern electric vehicle applications.
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paper_title: Analysis of electromagnetic performance of flux-switching permanent-magnet Machines by nonlinear adaptive lumped parameter magnetic circuit model

paper_content:

A nonlinear adaptive lumped parameter magnetic circuit model is developed to predict the electromagnetic performance of a flux-switching permanent-magnet machine. It enables the air-gap field distribution, the back-electromotive force (back-EMF) waveform, the winding inductances, and the electromagnetic torque to be calculated. Results from the model are compared with finite-element predictions and validated experimentally. The influence of end effects is also investigated, and optimal design parameters, such as the rotor pole width, the stator tooth width, and the ratio of the inner to outer diameter of the stator, are discussed.
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paper_title: Torque ripple minimization of doubly salient permanent-magnet motors

paper_content:

Due to the nature of salient poles in both the stator and rotor, the doubly salient permanent-magnet (DSPM) motor suffers from severe torque ripples. In this paper, the torque ripple of DSPM motors is analyzed, and the torque ripple factor is newly derived. A new approach, namely the conduction angle control, is proposed to minimize the torque ripple. Moreover, the genetic algorithm is employed to optimize the corresponding control angles. Computer simulation and experimental results are given to verify the proposed approach.
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paper_title: The flux-reversal machine: a new brushless doubly-salient permanent-magnet machine

paper_content:

A new brushless doubly-salient permanent-magnet machine called the flux-reversal machine is described. Design, analysis, construction, and experimental results for a prototype machine built as a single-phase, high-speed generator are presented. Qualitative comparisons are made with the other types of brushless machines in its class, using the flux-MMF diagram technique. An elementary CAD program developed for designing flux-reversal machines and the associated drive electronics is also described.
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paper_title: Novel permanent magnet motor drives for electric vehicles

paper_content:

Novel permanent magnet (PM) motor drives have been successfully developed to fulfil the special requirements for electric vehicles such as high power density, high efficiency, high starting torque, and high cruising speed. These PM motors are all brushless and consist of various types, namely rectangular-fed, sinusoidal-fed, surface-magnet, buried-magnet, and hybrid. The advent of novel motor configurations lies on the unique electromagnetic topology, including the concept of multipole magnetic circuit and full slot-pitch coil span arrangements, leading to a reduction in both magnetic yoke and copper, decoupling of each phase flux path, and hence an increase in both power density and efficiency. Moreover, with the use of fractional number of slots per pole per phase, the cogging torque can be eliminated. On the other hand, by employing the claw-type rotor structure and fixing an additional field winding as the inner stator, these PM hybrid motors can further provide excellent controllability and improve efficiency map. In the PM motors, by purposely making use of the transformer EMF to prevent the current regulator from saturation, a novel control approach is developed to allow for attaining high-speed constant-power operation which is particularly essential for electric vehicles during cruising. Their design philosophy, control strategy, theoretical analysis, computer simulation, experimental tests and application to electric vehicles are described.
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paper_title: Design and Control of a PM Brushless Hybrid Generator for Wind Power Application

paper_content:

In this paper, a new permanent magnet (PM) brushless hybrid machine is proposed and implemented for wind power generation. The originality is that a small dc field winding and an extra air-bridge are incorporated in the machine so that the air-gap flux can be effectively strengthened or weakened to online keep the output voltage constant throughout the whole wind speed range. The characteristics of flux linkage and no-load electromotive force (EMF) are analyzed by using the finite element method (FEM), and these results agree well with those from magnetic circuit analysis. Experimental results also verify that the proposed machine can produce a constant output voltage over a wide wind speed range
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paper_title: A novel stator doubly fed doubly salient permanent magnet brushless machine

paper_content:

A novel stator doubly fed doubly salient permanent magnet (PM) brushless machine is proposed. The novelty of this machine is to purposely add an extra flux path in shunt with each PM pole, hence amplifying the effect of flux weakening for constant power operation. Magnetic circuit analysis is adopted to illustrate the novelty. Machine flux paths and performance curves determined by a finite-element analysis are presented for various excitations. The corresponding results show that the proposed machine is promising for application to electric vehicles.
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paper_title: Memory motors

paper_content:

A new class of permanent-magnet (PM) machines, named memory motors for their ability to change the intensity of magnetization and memorize the flux density level in rotor magnets is described in the article. A memory motor can be built either as a variable-flux or pole-changing machine. In both machine types, the magnetization of PMs can be simply varied by a short current pulse, with no need for permanent demagnetizing current as in conventional internal PM machines at flux-weakening mode. The demagnetizing current flows through stator winding(s) supplied from the same source as the stator current. Memory motors combine advantages of a wound-rotor machine (variable rotor flux) with those of a wide-speed machine (no excitation losses), resulting in a unique machine concept that has the potential to find numerous applications in electric drives.
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paper_title: Novel wide range speed control of permanent magnet brushless motor drives

paper_content:

This paper presents a novel approach for the wide range speed control of a permanent magnet (PM) brushless motor drive, including both sinewave and squarewave versions. As compared with conventional flux-weakening control, the approach has definite advantages in that it can be applied to the squarewave PM brushless motor drive directly, and even to the motor drive with negligible mutual inductances between phase windings. Moreover, it is easier to implement than flux-weakening control because no coordinate transformation is needed. The key of this approach is to make use of the transformer EMF in such a way that it weakens the rotational EMF when the motor operates above the base speed, leading to the achievement of constant-power operation. Computer simulation and experimental results show that the proposed approach works well. >
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paper_title: Novel permanent magnet motor drives for electric vehicles

paper_content:

Novel permanent magnet (PM) motor drives have been successfully developed to fulfil the special requirements for electric vehicles such as high power density, high efficiency, high starting torque, and high cruising speed. These PM motors are all brushless and consist of various types, namely rectangular-fed, sinusoidal-fed, surface-magnet, buried-magnet, and hybrid. The advent of novel motor configurations lies on the unique electromagnetic topology, including the concept of multipole magnetic circuit and full slot-pitch coil span arrangements, leading to a reduction in both magnetic yoke and copper, decoupling of each phase flux path, and hence an increase in both power density and efficiency. Moreover, with the use of fractional number of slots per pole per phase, the cogging torque can be eliminated. On the other hand, by employing the claw-type rotor structure and fixing an additional field winding as the inner stator, these PM hybrid motors can further provide excellent controllability and improve efficiency map. In the PM motors, by purposely making use of the transformer EMF to prevent the current regulator from saturation, a novel control approach is developed to allow for attaining high-speed constant-power operation which is particularly essential for electric vehicles during cruising. Their design philosophy, control strategy, theoretical analysis, computer simulation, experimental tests and application to electric vehicles are described.
---
paper_title: Electrical Machines and Drives for Electric, Hybrid, and Fuel Cell Vehicles

paper_content:

This paper reviews the relative merits of induction, switched reluctance, and permanent-magnet (PM) brushless machines and drives for application in electric, hybrid, and fuel cellvehicles,withparticularemphasisonPMbrushlessmachines. The basic operational characteristics and design requirements, viz. a high torque/power density, high efficiency over a wide operatingrange,andahighmaximumspeedcapability,aswell as the latest developments, are described. Permanent-magnet brushless dc and ac machines and drives are compared in terms of their constant torque and constant power capabilities, and various PM machine topologies and their performance are reviewed. Finally, methods for enhancing the PM excitation torque and reluctance torque components and, thereby, improv- ing the torque and power capability, are described.
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paper_title: Design and Control of a PM Brushless Hybrid Generator for Wind Power Application

paper_content:

In this paper, a new permanent magnet (PM) brushless hybrid machine is proposed and implemented for wind power generation. The originality is that a small dc field winding and an extra air-bridge are incorporated in the machine so that the air-gap flux can be effectively strengthened or weakened to online keep the output voltage constant throughout the whole wind speed range. The characteristics of flux linkage and no-load electromotive force (EMF) are analyzed by using the finite element method (FEM), and these results agree well with those from magnetic circuit analysis. Experimental results also verify that the proposed machine can produce a constant output voltage over a wide wind speed range
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paper_title: New split-winding doubly salient permanent magnet motor drive

paper_content:

A new split-winding doubly salient permanent magnet (DSPM) motor drive is proposed. This DSPM motor drive offers the advantages of high power density, high efficiency, and wide speed range. The corresponding operation, analysis, implementation, and experimentation are successively presented. Finally, experimental results are used to confirm that the proposed DSPM motor drive offers high efficiency over a wide output power range, exhibits good dynamic performance, and extends the constant-power operation range significantly.
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paper_title: A novel stator doubly fed doubly salient permanent magnet brushless machine

paper_content:

A novel stator doubly fed doubly salient permanent magnet (PM) brushless machine is proposed. The novelty of this machine is to purposely add an extra flux path in shunt with each PM pole, hence amplifying the effect of flux weakening for constant power operation. Magnetic circuit analysis is adopted to illustrate the novelty. Machine flux paths and performance curves determined by a finite-element analysis are presented for various excitations. The corresponding results show that the proposed machine is promising for application to electric vehicles.
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paper_title: On-line optimal field-weakening control of permanent magnet brushless AC drives

paper_content:

An online field-weakening control strategy, which optimises performance independent of the motor parameters, is proposed for permanent magnet brushless AC motor drives. It facilitates maximum efficiency over the entire speed range, from constant torque to constant power operation, and is able to maximise the power capability in the field-weakening operating range.
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paper_title: Field-weakening performance of interior permanent magnet motors

paper_content:

This paper compares the field-weakening under rated and overload conditions of synchronous reluctance and interior permanent magnet motors against that of a baseline 2.2 kW induction machine. Four prototype rotors based on axially-laminated and multiple-barrier designs were built and tested in the induction machine stator. Field-weakening performance was estimated based on 50 Hz load tests at reduced voltage. It was found that the performance of the axially-laminated synchronous reluctance machine was comparable with the induction machine while the interior permanent magnet motors offered significantly better output power above rated speed. The multiple-barrier interior permanent magnet motor design gave the most promising field-weakening performance.
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paper_title: High-Speed Control of IPMSM Drives Using Improved Fuzzy Logic Algorithms

paper_content:

This paper presents an improved fuzzy logic controller (FLC) for an interior permanent magnet synchronous motor (IPMSM) for high-performance industrial drive applications. In the proposed control scheme for high-speed operations above the rated speed, the operating limits of IPMSM are expanded by incorporating the maximum torque per ampere operation in constant torque region and the flux-weakening operation in constant power region. The power ratings of the motor and the inverter are considered in developing the control algorithm. A new and simple FLC is utilized as a speed controller. The FLC is developed to have less computational burden, which makes it suitable for real-time implementation, particularly at high-speed operating conditions. The complete drive is implemented in real-time using digital signal processor (DSP) controller board DS 1102 on a laboratory 1-hp IPM motor. The efficiency of the proposed control scheme is evaluated through both experimental and computer simulation results. The proposed controller is found to be robust for high-speed applications
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paper_title: Novel permanent magnet motor drives for electric vehicles

paper_content:

Novel permanent magnet (PM) motor drives have been successfully developed to fulfil the special requirements for electric vehicles such as high power density, high efficiency, high starting torque, and high cruising speed. These PM motors are all brushless and consist of various types, namely rectangular-fed, sinusoidal-fed, surface-magnet, buried-magnet, and hybrid. The advent of novel motor configurations lies on the unique electromagnetic topology, including the concept of multipole magnetic circuit and full slot-pitch coil span arrangements, leading to a reduction in both magnetic yoke and copper, decoupling of each phase flux path, and hence an increase in both power density and efficiency. Moreover, with the use of fractional number of slots per pole per phase, the cogging torque can be eliminated. On the other hand, by employing the claw-type rotor structure and fixing an additional field winding as the inner stator, these PM hybrid motors can further provide excellent controllability and improve efficiency map. In the PM motors, by purposely making use of the transformer EMF to prevent the current regulator from saturation, a novel control approach is developed to allow for attaining high-speed constant-power operation which is particularly essential for electric vehicles during cruising. Their design philosophy, control strategy, theoretical analysis, computer simulation, experimental tests and application to electric vehicles are described.
---
paper_title: Efficiency enhancement of permanent-magnet synchronous motor drives by online loss minimization approaches

paper_content:

In this paper, a new loss minimization control algorithm for inverter-fed permanent-magnet synchronous motors (PMSMs), which allows for the reduction of the power losses of the electric drive without penalty on its dynamic performance, is analyzed, experimentally realized, and validated. In particular, after a brief recounting of two loss minimization control strategies, namely, the "search control" and the "loss-model control," both a new modified dynamic model of the PMSM (which takes into account the iron losses) and an innovative "loss-model" control strategy are presented. Experimental tests on a specific PMSM drive employing the proposed loss minimization algorithm have been performed, aiming to validate the actual implementation. The main results of these tests confirm that the dynamic performance of the drive is maintained, and in small motors enhancement up to 3.5% of the efficiency can be reached in comparison with the PMSM drive equipped with a more traditional control strategy.
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paper_title: An advanced permanent magnet motor drive system for battery-powered electric vehicles

paper_content:

Availability of high-energy neodymium-iron-boron (Nd-Fe-B) permanent magnet (PM) material has focused attention on the use of the PM synchronous motor (PMSM) drive for electric vehicles (EVs). A new Nd-Fe-B PMSM is proposed for the drive system, which possesses high power density and high efficiency, resulting in greater energy and space savings. The design and optimization of the motor employs finite element analysis and computer graphics. Increasingly, a new PWM inverter algorithm is developed for the drive system, which can handle the nonconstant battery voltage source. An efficiency optimizing control is adopted to further improve the energy utilization of the drive system. Both the control strategy and the PWM generation are implemented in a single-chip microcontroller. As a result, the motor drive achieves high power density, high efficiency, and compactness. A prototype of the 3.2 kW battery-powered drive system has been designed and built for an experimental mini-EV.
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paper_title: Problems associated with the direct torque control of an interior permanent-magnet synchronous motor drive and their remedies

paper_content:

This paper investigates problems associated with the implementation of a direct torque control (DTC) strategy for an interior permanent-magnet synchronous motor drive. The DTC technique is increasingly drawing attention because of elimination of current controllers and, hence, their inherent delays, and elimination of the rotor position sensor. The latter advantage perhaps is the main impetus for considering this new approach of torque control. Problems associated with this controller, namely, the offset in the current measurements, the stator resistance variation, and the requirement of initial rotor position are addressed in this paper. Ways of mitigating of these problems are also investigated in this paper. These are evaluated with modeling and experimental studies, results of which are also presented.
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paper_title: Predictive direct torque control for the PM-synchronous machine

paper_content:

The paper shows that a predictive digital control combined with the principle of the direct torque control leads to an excellent dynamic behavior of the permanent magnet excited synchronous machine and is a real alternative to the classical field orientated control. The advantages are the constant switching frequency and the predictable torque ripple. The set up times of the torque are reduced compared with the classical control. The application in servo-drives in which the rotor position is always measured can be easily realized using a commercial DSP. Numerous simulations and measurements confirm the theoretical work.
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paper_title: New self-tuning fuzzy PI control of a novel doubly salient permanent-magnet motor drive

paper_content:

In a doubly salient permanent-magnet (DSPM) motor drive, it is difficult to get satisfied control characteristics by using a normal linear proportional plus integral (PI) controller due to the high nonlinearity between speed and current or torque. Hence, a new self-tuning fuzzy PI controller with conditional integral, which is performed by a single-chip N87C196KD, is proposed. The initial parameters of the controller are optimized by using genetic arithmetic. Simulation and experiments on the newly proposed 8/6-pole DSPM machine have shown that the proposed new self-tuning fuzzy PI controller offers better adaptability than the normal linear PI control and that the developed motor drive offers better steady-state and dynamic performances.
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paper_title: Application of Artificial Neural Network to Robust Speed Control of Servodrive

paper_content:

This paper deals with the problem of robust speed control of electrical servodrives. A robust speed controller is developed using an artificial neural network (ANN), which creates a nonlinear characteristic of controller. An original method of neural controller synthesis is presented. The synthesis procedure is performed in two stages. The first stage consists in training the ANN and at the second stage controller settings are adjusted. The use of the proposed controller synthesis procedure ensures robust speed control against the variations of moment of inertia and stator magnetic flux. Simulations and laboratory results validate the robustness of the servodrive with permanent magnet synchronous motor
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paper_title: Mechanical sensorless speed control of permanent-magnet AC motors driving an unknown load

paper_content:

A new sensorless scheme for high-performance speed control of permanent-magnet ac motors (PMACMs) driving an unknown load is proposed. This scheme uses an extended nonlinear reduced-order observer to estimate the induced electromotive force (EMF) and load torque. From the estimated variables, the rotor position, the rotor speed, and the position derivative of flux are calculated and are used to close the control loop. In order to improve the drive performance, the estimated load torque is incorporated as a feedforward signal in the closed control loop. In addition, the proposed sensorless PMACM drive allows the torque-ripple and copper-loss minimization for motors with an arbitrary EMF waveform. Simulation and experimental results to validate the proposal are presented in this paper.
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paper_title: New self-tuning fuzzy PI control of a novel doubly salient permanent-magnet motor drive

paper_content:

In a doubly salient permanent-magnet (DSPM) motor drive, it is difficult to get satisfied control characteristics by using a normal linear proportional plus integral (PI) controller due to the high nonlinearity between speed and current or torque. Hence, a new self-tuning fuzzy PI controller with conditional integral, which is performed by a single-chip N87C196KD, is proposed. The initial parameters of the controller are optimized by using genetic arithmetic. Simulation and experiments on the newly proposed 8/6-pole DSPM machine have shown that the proposed new self-tuning fuzzy PI controller offers better adaptability than the normal linear PI control and that the developed motor drive offers better steady-state and dynamic performances.
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paper_title: Hybrid rotor position observer for wide speed-range sensorless PM motor drives including zero speed

paper_content:

This paper addresses the problem of wide speed-range sensorless control of a surface-mount permanent-magnet (SMPM) machine including zero-speed operation. A hybrid structure integrating a flux observer and signal-injection techniques is proposed, which results in a rotor position signal independent of motor parameters at low and zero speed. Although the SMPM machine typically has a very low geometric saliency, the injection technique is effective in tracking the saturation-induced saliency produced by the stator flux. Experimental results are presented showing an excellent performance for both the sensorless speed and position control using an off-the-shelf SMPM machine.
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paper_title: Predictive direct torque control for the PM-synchronous machine

paper_content:

The paper shows that a predictive digital control combined with the principle of the direct torque control leads to an excellent dynamic behavior of the permanent magnet excited synchronous machine and is a real alternative to the classical field orientated control. The advantages are the constant switching frequency and the predictable torque ripple. The set up times of the torque are reduced compared with the classical control. The application in servo-drives in which the rotor position is always measured can be easily realized using a commercial DSP. Numerous simulations and measurements confirm the theoretical work.
---
paper_title: Efficiency enhancement of permanent-magnet synchronous motor drives by online loss minimization approaches

paper_content:

In this paper, a new loss minimization control algorithm for inverter-fed permanent-magnet synchronous motors (PMSMs), which allows for the reduction of the power losses of the electric drive without penalty on its dynamic performance, is analyzed, experimentally realized, and validated. In particular, after a brief recounting of two loss minimization control strategies, namely, the "search control" and the "loss-model control," both a new modified dynamic model of the PMSM (which takes into account the iron losses) and an innovative "loss-model" control strategy are presented. Experimental tests on a specific PMSM drive employing the proposed loss minimization algorithm have been performed, aiming to validate the actual implementation. The main results of these tests confirm that the dynamic performance of the drive is maintained, and in small motors enhancement up to 3.5% of the efficiency can be reached in comparison with the PMSM drive equipped with a more traditional control strategy.
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paper_title: Modern Electric Vehicle Technology

paper_content:

1. Engineering Philosophy of EV Developments 2. EV and HEV Developments 3. EV Systems 4. HEV Systems 5. Electric Propulsion 6. Energy Sources 7. EV Auxiliaries 8. EV Simulation 9. EV Infrastructure 10. Energy, environment and economy
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paper_title: A novel high-performance magnetic gear

paper_content:

Mechanical gearboxes are used extensively to match the operating speed of prime-movers to the requirements of their loads. Although, high system torque densities can be achieved, gear lubrication and cooling are often required, whilst noise, vibration and reliability can be significant issues. The paper describes the design and performance of a magnetic gear, which employs rare-earth magnets, which simulation studies have shown to have a transmitted torque density exceeding 100 kNm/m/sup 3/.
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paper_title: Design of a Magnetic-Geared Outer-Rotor Permanent-Magnet Brushless Motor for Electric Vehicles

paper_content:

This paper proposes a novel in-wheel motor, which artfully integrates a magnetic gear into a permanent-magnet brushless (PMBL) DC motor so that they can share a common PM rotor, hence offering both high efficiency and high power density. Moreover, the low-speed requirement for direct driving and the high-speed requirement for compact motor design can be achieved simultaneously. A 2-kW 600/4400-rpm magnetic-geared outer-rotor PMBL DC motor is designed and analyzed, which is particularly suitable for battery-powered electric motorcycles
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paper_title: Design and Analysis of a Stator-Doubly-Fed Doubly-Salient Permanent-Magnet Machine for Automotive Engines

paper_content:

This paper presents a new outer-rotor stator-doubly-fed doubly-salient permanent-magnet (SDF-DSPM) machine, which can be used as the integrated starter-generator for modern automobiles and mild hybrid electric vehicles. The key of the proposed machine is to incorporate both dc field windings and PMs in the inner stator, hence, offering a compact arrangement of hybrid field excitations. While armature windings are located in salient poles of the outer stator, the outer rotor is simply composed of salient poles without windings or PMs. In addition, an air bridge is purposely created in shunt with each PM in the inner stator, hence, providing an amplification effect for flux regulation. With this idea, the air-gap flux can be strengthened or weakened with a small dc field current so that the electromagnetic torque and induced electromotive force (EMF) can be effectively regulated. The newly designed SDF-DSPM machine is analyzed by using both the magnetic circuit model and finite element method, and assessed by performance simulation
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paper_title: The Study of the Operation Modes and Control Strategies of an Advanced Electromechanical Converter for Automobiles

paper_content:

To enhance the performance of hybrid electric vehicle and continuously variable transmission, and to achieve more varied operation modes, a novel breed of integrated electromechanical converter is presented, such as electrical variable transmission (EVT) and four-quadrant transducer. Synthesizing two electric machines, they are essentially electromagnetic theory-based converters with the function of speed, torque, and energy regulation. The feature of flexible and variable control makes them very suitable for use in automobiles, especially in hybrid electric vehicles, as a continuously variable transmission and integrated starter and generator. Furthermore, the operation of the internal combustion engine is optimized, and the reduction of fuel consumption and the improvement of vehicle performance are also achieved. Corresponding to different road loads and driver demands, several operating states and control strategies are possible. Based on a simplified structure, the mathematical model of the EVT has been built, and its power flow and control strategies under different operation modes, are also analyzed
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paper_title: Hybrid electric vehicle propulsion system architectures of the e-CVT type

paper_content:

There is now significant interest in hybrid electric vehicle (HEV) propulsion systems globally. Economics play a major role as evidenced by oil prices in North America pressing upwards of $100/Bbl coupled with a customer preference for full size crossover and sport utility vehicles. The situation in Oceania is milder, but emerging markets such as China are experiencing automotive sector growth rates of 37%/year. Europe remains least affected by hybrids since nearly 47% of all new vehicles sold are diesel fueled and have economy ratings on par with that of gasoline-electric hybrids. In the global economy there are presently some 57 Mil new vehicles manufactured each year. Toyota and Honda have projected that HEVs will be 10 % to 15 % of the U.S. market by 2009, with Toyota raising the bar further by stating they will produce 1 Mil hybrids a year in the 2012 time frame. Hybrid propulsion system types are only vaguely comprehended by the buying public, and to a large measure, even by technical professionals. This paper addresses this latter issue by presenting a summary of the globally accepted standard in hybrid power trains-the power split architecture, or more generically and in common usage, the electronic-continuously variable transmission
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paper_title: A four-quadrant HEV drive system

paper_content:

A research project for a drive system for hybrid electric vehicles is described. The main target is to develop a system, which enables the combustion engine (ICE) to operate at optimal conditions, thus decreasing fuel consumption and emissions. The electrical system consists primarily of an electrical machine with two rotors and one stator, two converters and a battery. The concept enables the vehicle to be operated at different speed and torque independent of the engine's operating point. The sizes of the electrical components are limited depending on the required variation in speed and torque. Simulations show a significant reduction of fuel consumption for vehicles in urban traffic. The concept, which is very compact, can be implemented with both radial and axial flux electrical machines. Several modes of operation are possible, such as hybrid mode, electrical mode, pure ICE driving, cranking and regenerative braking.
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paper_title: The electric variable transmission

paper_content:

First, an electromechanical converter with two mechanical ports and one electrical port (consisting of two concentric machines and two inverters) is considered. This converter works as a continuously variable transmission between the mechanical ports and may, e.g., replace the clutch, gearbox, generator, and starter motor in a motor vehicle. The working principle of this converter is explained. Next, a new converter, the electric variable transmission (EVT), is presented. This converter has similar properties, but is smaller and lighter. The EVT may be seen as built up from two concentric induction machines with a combined relatively thin yoke. Thus, we obtain one electromagnetic device instead of two magnetically separated devices. The working principle of the EVT is explained, and its losses are discussed
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Title: Overview of Permanent-Magnet Brushless Drives for Electric and Hybrid Electric Vehicles

Section 1: INTRODUCTION
Description 1: Introduce the limitations of internal combustion engine vehicles and the potential of electric vehicles (EVs) and hybrid electric vehicles (HEVs). Discuss the basic characteristics desired in electric drives for EVs and the attractiveness of permanent-magnet (PM) brushless (BL) drives. Explain the purpose and structure of the paper.

Section 2: CLASSIFICATION OF EV DRIVES
Description 2: Explain the classification of different types of electric drives for EVs, namely, dc, induction, switched reluctance (SR), and PM brushless (BL) drives. Discuss the characteristics and applications of each type.

Section 3: PM BL MACHINE TOPOLOGIES
Description 3: Discuss various PM BL machine topologies including radial-field, axial-field, and linear-field morphologies. Provide details of rotor and stator PM BL machine topologies, hybrid PM BL machine topologies, and memory PM BL machine topologies. Compare these topologies based on key features relevant to EV drives.

Section 4: PM BL DRIVE OPERATIONS
Description 4: Describe the operations of PM BL drives including BLAC and BLDC operations. Explain methods for constant-power operation and efficiency-optimized control (EOC).

Section 5: PM BL DRIVE CONTROL STRATEGIES
Description 5: Discuss various control strategies for PM BL drives such as direct torque control (DTC), artificial intelligent control (AIC), and position-sensorless control (PSC). Compare the advantages and disadvantages of different strategies.

Section 6: INTEGRATIVE TECHNOLOGIES
Description 6: Identify and discuss emerging integrative technologies in PM BL drive systems, such as magnetic-geared PM BL drives, integrated starter-generator (ISG) systems, and electric variable transmission (EVT) systems for EVs and HEVs.

Section 7: CONCLUSION
Description 7: Summarize the overview of PM BL drives for EVs and HEVs, emphasizing key points on machine topologies, operations, control strategies, and emerging research directions.