Design and analysis of a new permanent magnet brushless DC machine

A new permanent magnet (PM) brushless dc machine with a unique feature of flux regulation is presented. The machine offers the merits of high density, high efficiency, high starting torque and wide constant power speed range.published_or_final_versio

A permanent-magnet double-stator integratedstarter-generator for hybrid electric vehicles

This paper presents a new permanent magnet double-stator integrated-starter-generator (ISG) for hybrid electric vehicles (HEVs). Compared with conventional PM electric machines, it has the advantage that currents of both the inner and outer stators produce electromagnetic torque and two air-gaps can deliver the output torque, thus improving the torque density and providing a high starting torque for cold cranking. Because of the nature of doublestator windings, the machine can flexibly change their connections, hence providing a constant output voltage over a wide speed range for battery charging. By using time-stepping finite element method (TS-FEM), the steady-state and dynamic performance of the machine is analyzed. Hence, due to the high starting torque and good controllability, this proposed ISG is desirable for HEVs application. A three-phase 22-pole 2 kW prototype is designed and built for experimentation verification. © 2008 IEEE.published_or_final_versio

Application of linear magnetic gears for pseudo-direct-drive oceanic wave energy harvesting

Session AZ: Magnetic Machine (Poster Session): AZ-07This paper proposes a linear permanent magnet (PM) machine for direct-drive wave energy harvesting by using a linear magnetic gear. The proposed machine consists of a linear magnetic gear cascaded with a linear PM generator in which the high-speed mover of the linear magnetic gear and the translator of the PM generator artfully shares with the same shaft. In short, the slow reciprocating wave motion is directly captured by the low-speed mover of the gear, and then amplified in speed via the gear to actuate the generator, hence producing higher output voltage. By using finite element analysis, the steady and dynamic performances are analyzed, which confirms that the proposed machine can offer higher power density and higher efficiency than its counterpart. © 2011 IEEE.published_or_final_versionThe IEEE International Magnetic Conference (INTERMAG2011), Taipei, Taiwan, 25-29 April 2011. In IEEE Transactions on Magnetics, 2011, v. 47 n. 10, p. 2624-262

Optimal efficiency control of PM hybrid motor drives for electrical vehicles

The paper deals with the control of a novel brushless PM hybrid motor to optimize its efficiency. The approach is to adaptively adjust the field current to minimize the total loss based on its potential for a high efficiency over a wide torque-speed region. The optimal controller has good performance for electrical vehicles.published_or_final_versio

Transient analysis of a new outer-rotor permanent-magnet brushless DC drive using circuit-field-torque coupled time-stepping finite-element method

In this paper, a new outer-rotor permanent magnet (PM) brushless dc drive is designed and analyzed. To enable this drive applicable to electric vehicles, its transient performances at both normal and flux-weakening operations are particularly focused. The distinct feature in design is due to the new motor configuration including the outer-rotor topology, the multipole magnetic circuit and the full slot-pitch coil span arrangement. The distinct feature in analysis is due to the development of the circuit-field-torque coupled time-stepping finite-element method. The proposed PM brushless dc drive is prototyped. The analysis results are verified by experimental measurement.published_or_final_versio

A permanent-magnet hybrid brushless integrated starter-generator for hybrid electric vehicles

A new permanent-magnet (PM) hybrid brushless (PMHB) machine is proposed and implemented as the integrated startergenerator (ISG) for hybrid electric vehicles (HEVs). It has the advantages of higher torque density than other PMHB machines and much wider speed range than other PM brushless machines. The key is to tune its dc-field winding current in such a way that three major modes of ISG system operation for HEVs, namely, engine cranking, battery charging, and torque boosting, can be achieved effectively. The finite-element method is employed to simulate its steady-state and dynamic performances. Finally, a 2-kW prototype is constructed and tested to experimentally verify the simulation results and the validity of the proposed ISG system. © 2010 IEEE.published_or_final_versio

Design of a novel phase-decoupling permanent magnet brushless ac motor

This paper presents a phase-decoupling permanent magnet brushless ac motor which can offer better controllability, faster response, and smoother torque than its counterparts. The key is due to its different motor configuration and simple scalar control. The motor configuration is so unique that it inherently offers the features of phase decoupling, flux focusing, and flux shaping, hence achieving independent phase control, fast response, and smooth torque. The scalar control is fundamentally different from the complicated vector control. It can achieve direct torque control through independent control of the phase currents. The proposed motor is prototyped and experimentally verified. © 2005 American Institute of Physics.published_or_final_versio

Analysis of eddy-current loss in a double-stator cup-rotor PM machine

In this paper, a new double-stator cup-rotor permanent-magnet brushless DC (PMBDC) machine is proposed and analyzed. Since the machine structure is so unique while its operating principle is so distinct, a numerical field approach, namely the circuit-field-torque grid-model time-stepping finite-element method (CFT-GM-TS-FEM), is newly developed to analyze the steady-state and dynamic characteristics of the machine. Particularly, the analysis of eddy-current loss in both the PMs and iron core of the machine is conducted. Experimental results are given for verification. © 2008 IEEE.published_or_final_versio

A Survey of Classical and Recent Results in RLC Circuit Synthesis

This is the final version of the article. Available from the publisher via the link in this record.The motivation provided by mechanical network synthesis to make a fresh attack on certain questions in circuit synthesis will be briefly recalled. The classical early work on RLC synthesis, beginning with the works of Foster and Cauer and culminating in the Bott-Duffin construction, will be explained in a tutorial manner. Recent work on RLC synthesis by Jiang and Smith and Hughes and Smith will be introduced. The proof in T.H. Hughes and M.C. Smith, 2014, " On the minimality and uniqueness of the Bott-Duffin procedure " , IEEE Trans. Aut. Contr., (to appear), showing the surprising result that the Bott-Duffin construction for a biquadratic minimum function is the simplest possible among series-parallel circuits, will be explained.This work was supported by the Engineering and Physical Sciences Research Council under Grant EP/G066477/

Comparison of stator-permanent-magnet brushless machines

This paper quantitatively compares two emerging stator-permanent-magnet (PM) machines, namely, the doubly salient PM and the PM hybrid brushless types. Both of them are attractive for electric vehicles and wind power generation. For comparison, both machines adopt the outer-rotor 36/24-pole topology and are designed based on the same peripheral dimensions. By using the circuit-field-torque time-stepping finite element analysis (CFT-TS-FEM), both steady-state and transient performances of the two machines are critically compared. © 2008 IEEE.published_or_final_versio