A short stroke and large thrust axial magnetized tubular permanent magnet linear launcher (TPMLL) with non-ferromagnetic rings is presented in this paper. Its 3D finite element (FE) models are established for sensitivity analyses on some parameters, such as air gap thickness, permanent magnet thickness, permanent magnet width, stator yoke thickness and four types of permanent magnet material,...
Recently, brushless double-fed machines (BDFMs) have been widely developed due to the wide application prospects in electric power generation fields with variable speed, constant voltage and constant frequency performances and speed regulating systems using large capacity motor. The magnetic field generated by the two sets of windings, which are both located in the BDFM stator, indirectly...
Recently, flux-switching permanent magnet (FSPM) motors have been widely developed due to the merits of high power density, essentially sinusoidal back-EMF, and high fault-tolerance capability. However, FSPM motors usually suffer from disadvantages of high usage of rare-earth permanent magnet (PM) material and relatively low flux-weakening capability. So hybrid excitation flux-switching (HEFS)...
Tubular permanent magnet (TPM) motors have been applied to many direct drive systems such as electromagnetic suspension. Double-stator structure can take best use of the motor space and increase the slot area. The flux-modulation structure is based on magnetic gear effect, which makes full use of effective harmonic components of magnetic field. Thus, this structure can increase the force...
Among the various industries, the use of IPMSM in electric vehicle is increasing.In particular, in the case of an electric vehicle drive motor, the mechanical strength of the rotor is important because it operates in a high-speed operation region.Therefore, the double layer V-shaped magnet type IPMSM is more widely used in electric vehicles currently selling, because the double layer V-shaped...
Permanent magnet (PM) motors are field magnetic fluxes generated from PMs without external current input, which is advantageous in terms of power density and efficiency than non-PM motors. Due to these advantages, it has recently been applied in various fields such as electric vehicle and home appliances. The PM motor used mainly in the past was a surface mounted type in which PMs were...
We have been studying on a superconducting motor for highly efficient transportation equipment. Target motor of our study is a High Temperature Superconducting Induction/Synchronous Motor (HTS-ISM). Basic structure of the HTS-ISM is the same as that of so-called squirrel-cage induction motor, and HTS tapes are used in its rotor bars and end rings. Based on experiments and analysis, it has been...
Compared to radial magnetization, Halbach permanent-magnet (PM) array inherits some attractive features: strong field intensity, self-shielding effect, near-sinusoidal airgap flux density distribution. Due to the difficulty in realizing continuous magnetization direction on single PM annulus, Halbach PM arrays are generally realized by discrete PM segments. In most cases, the magnetization...
In general, Spoke type Permanent Magnet Synchronous Motor (PMSM) has intense air gap flux density due to its magnet arrangement. However, variation of machine performance is severe due to its design variables, such as air-gap length and magnet size. On the other hand, Surface Mounted PMSM (SPMSM) is less sensitive to change of variables that are mentioned above. In this study, we examine the...
High-speed permanent magnet (PM) machines are used in applications such as machining spindles, generation and storage of energy in vehicles, gas blowers, and other specialized applications. High-speed PM machines exhibit high efficiency, energy density, and dynamic capability. However, in these machines, overheating in rotors due to power loss can lead to problems because, unlike stators,...
Permanent magnet (PM) machines are becoming popular as a key technology for applications such as home appliances, industrial tools, and electric vehicles. This is because of their high efficiency, high power density, and low maintenance costs. It is very important to consider the power losses in the initial design stage itself, because they determine the efficiency of the machine and have a...
Efficiency is an important index to evaluate the performance of an electric machine. Core loss takes a big part of the total losses of an electric machine. Amorphous alloy material (AAM) has much lower core loss than that of traditional silicon steel. An outer-rotor permanent magnet synchronous machine (OR-PMSM) with amorphous stator core is proposed in this paper, which exhibits higher...
Flux reversal machines (FRMs) have a stator with permanent magnets (PMs) mounted on the surface each teeth and a reluctance rotor. As the flux field excited by the PMs is almost constant, the magnitude and phase of the stator current are often adjusted to realize the flux-weakening operation, but it usually sacrifices the output torque. As we know, HTS wound field machines can easily adjust...
Recently, various types of electric motor are applied to vehicle traction field because of strengthened environmental law. In general, Interior Permanent Magnet Synchronous Motor(IPMSM) has high power density and efficiency due to reluctance torque by adopting permanent magnet. By these advantages, IPMSM is widely used in Electric Vehicle(EV) traction motor.In case of EV traction motor,...
Conventional bearingless PM motors usually suffer from the problems of mechanical integrity and thermal instability due to their PMs located in the rotor, which lead to a discount of the maximum electric loading performance. In order to solve the problems, the bearingless flux-switching permanent magnet (BFSPM) motors appear in recent years. BFSPM motor combines the characteristics of...
Abstract- The stator-magnet moving-iron transversal-flux linear oscillatory machine (SMTLOM) offers the merits of high reliability and robustness, high material utilization ratio, low fabrication difficulty and cost and so on. However, due to its iron mover, the weight of moving structure is relatively higher than that of moving-magnet linear oscillatory machine (MLOM). Consequently, a rather...
The Brushless DC (BLDC) motor is widely applied in various fields, such as tractions, communication devices, and home appliances, by virtue of its high-power density, wide operating range, high efficiency and simple drive system. Two kinds of BLDC motors, “Y-connection, 2-phase excitation system” and “∆-connection, 3-phase excitation system”, have many differences. A major difference is the...
Our project research group has proposed a High Temperature Superconducting Induction Synchronous Motor (HTS-ISM) for the next generation transportation equipment, such as ships, trains, buses, and automobiles. The basic structure of the proposed HTS-ISM is as same as that of the traditional squirrel-cage induction motor. The difference is replacing the rotor (secondary) windings to the HTS...
Bearingless synchronous reluctance motors (BSRMs) have received more and more attention in recent years. Besides some general advantages of non-friction, high critical speed and non-lubrication of bearingless motors (BMs), the BSRM have some additional characteristics of simple structure, low loss and low temperature rising. Therefore, BSRMs have wide application prospect in some special...
Recently electric tools have been widely used in industrial applications and human livings, and will be increased very greatly in near future. Till now, most electric tools have been driven by concatenated induction machine, which suffers big volume, low torque density, low efficiency, poor reliability, etc. Fortunately, single-phase doubly salient permanent magnet machine (SP-DSPMM) has been...
Traditional heteropolar radial hybrid magnetic bearing (HRHMB) with eight poles has been widely applied in high-speed applications, such as flywheel energy storage system (FESS), because of its simple structure, low power loss, and high critical speed. However, this topology suffers large displacement stiffness, magnetic coupling, and non-negligible rotor iron loss. To overcome these...
In the past two decades, a bearingless synchronous reluctance motor (BSynRM) was proposed and developed. Besides the advantages of the traditional bearingless motors, the BSynRMs have the advantages of simple structure, low cost, low losses and can realize high speed operation using flux weakening control. Therefore, the BSynRMs have broad application prospects in vacuum, high speed, high...
By using the powder metallurgy technology and magnetic isotropy characteristic of the soft magnetic composite (SMC) material, various kinds of permanent magnet (PM) machine can be designed and fabricated easily. However, if the torque density of the PM machine with SMC cores is much lower than that with the silicon steels, if it is designed with the traditional structures and methods. In the...
The novel coil assisted reluctance motor is a kind of high torque DC motor combined with traditional permanent magnet brushless DC motor and switched reluctance motor. The motor with double sets of armature windings and the central coil (field winding) which is installed between two-stator-rotor by axial excitation has a 9\6 symmetric double salient pole structure. Based on the special...
This paper describes an innovative synthesis rotor geometry technique of permanent magnet assisted synchronous reluctance motor (PMAREL) with different flux barrier rotor shapes. The two symmetric rotor optimizations are examined and synthesis to establish the best asymmetric rotor geometry. The research results point out that the synthesis asymmetric rotor geometry is a more satisfying...
We have conducted research and development on a high-temperature superconducting motor, which has been expected as a next generation transportation equipment. Our target motor is so-called high-temperature superconducting induction/synchronous motor (HTS-ISM). The HTS-ISM has the similar structure as a squirrel cage induction motor, but replaces the winding with a HTS wire. Basically, by...
In order to improve the fault tolerant (FT) capability suitable for high reliability operation, FT teeth and concentrated windings are designed in two FT flux-switching permanent-magnet machines, namely 10/18-pole and 10/19-pole. However, they still suffer from vibration and noise due to radial force fluctuation. This paper compares the vibration characteristic of both machines. Because odd...