The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper presents a comparative study of three types of doubly salient machines (DSMs), i.e. wound field variable flux machines (VFMs), hybrid-excited stator slot permanent magnet machines (HSSPMs), and stator slot permanent magnet machines (SSPMs). Two dimensional finite element (FE) modelling is carried out to investigate the electromagnetic performance of the VFM and the SSPM based on a global...
Vernier Permanent-magnet machine (VPMM) has been recognized in recent years as a substitute for permanent magnet synchronous machines (PMSM) in direct-drive applications such as wind turbine generators, motorcycles and electric vehicle/hybrid electric vehicle (EV/HEV) [1].
The material and interface engineering of magnetic tunnel junctions (MTJ) is the key for the future of spin transfer torque based random access memories (STT-RAM).
Since vernier permanent-magnet machine (VPMM) has the merit of low-speed operation with high output torque due to the “magnetic-gearing” effect [1], they have been used in the direct-drive applications such as wind power generator, electric vehicle/hybrid electric vehicle (EV/HEV) [2,3].
A fault-tolerant direct torque control (DTC) strategy for a brushless dc (BLDC) motor with a single sided matrix converter (SSMC) for an electrohydrostatic actuator system in aerospace application is proposed in this paper. The voltage is divided into seven levels, a torque hysteresis control is applied to each phase, voltage of different levels are provided to the motor to control the torque. A Matlab/Simulink...
Low-speed direct-drive gearless machines are highly desirable for electric vehicle/hybrid electric vehicle (EV/HEV) propulsion due to the elimination of the associated gear wear, oil maintenance and acoustic problems. Conventional gearless direct-drive permanent magnet (PM) machines generally suffer from heavy weight, structural bulkiness, and lubrication problems. Due to the “magnetic-gearing” effect,...
Memory motors [1] [2] equipped with either single low-coercive force (LCF) or hybrid magnets have been extensively investigated due to the elimination of the associated excitation loss during the flux adjustment. Thus, they enable high efficiency operation within a wide range of speeds and loads. Very recently, switched-flux topologies that feature high torque density, simple rotor, and expedient...
Current-induced spin-orbit torque (SOT) is a very recently discovered phenomenon which provides efficient ways to control and manipulate the magnetization. It allows to use the spin-orbit interaction in the bulk or at the interface of a heavy metal (HM) to inject angular momentum in an adjacent ferromagnet (FM) [1-3]. Even though its origin either from Rashba or spin Hall effects is still under debate,...
Nowadays, numerous electrical machine topologies have been proposed and extensively investigated, which can extend the operating speed range together with the improvement of flux weakening capability without scarifying high efficiency. Amongst these machine topologies, variable-flux permanent magnet machines (VFPMs) are a competent candidate for electric vehicle/hybrid electric vehicle (EV/HEV) propulsion.
Traditional direct-drive permanent magnet synchronous machine (PMSM) suffers from large bulk and complex topology structure [1], which extremely limits its industrial applications. As a novel embranchment of PMSM, PM vernier machine (PMVM) incorporates the magnetic gear effects into conventional PMSM producing high torque at a relatively low speed, which is desirable for direct-drive applications...
The linear-rotary permanent magnet actuator (LRPMA) has been widely used in industrial manufacturing, automation control field and so on. The mover of developed LRPMA needs a lot of NdFeB material with the Halbach structure. In order to decrease the amout of NdFeB, a novel LRPMA is proposed using interlaced poles, namely, permanent magnet (PM) poles and iron poles, as shown in Fig.1 (a), (b). The...
Pole-changing permanent magnet (PM) machines, which can offer wide operating speed range, have attracted global attention in industry application [1-3]. However, the previous pole-changing PM machines adopting distributed winding, suffer from lengthy end winding and relatively low efficiency. Therefore, this paper presents a new variable flux pole-changing PM memory machine (VF-PCPMMM) employing fractional...
The spin-transfer torque (STT) phenomenon has recently been utilized for magnetic nano spin-transfer torque oscillators (STO) in patterned or nano-contact spin valves and magnetic tunnel junctions (MTJ). For applications, synchronization of multiple oscillators to achieve a higher microwave power and lower bandwidth is required. In order to realize such synchronization, a mutual feedback system among...
In this paper, we first derive an analytical formulation for capacitance prediction of multi-conductor and multi-dielectric system. A simulation model based on this formulation is then developed. By introducing the effective capacitance, we also propose a new methodology to measure the capacitance for multi-conductor system. Results from simulated model are compared with measurement data. It shows...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.