Flux-switching permanent magnet (FSPM) motors have gained increasing attention in the electric vehicles (EVs) applications due to the advantages of high power density, high efficiency. However, the heat sources of both permanent magnet (PM) and armature winding are located on the limited stator space in the FSPM motors, which may result in the PM overheated and irreversible demagnetization caus...

2014 The model of the potential function V(x), for the hysteresis cycles in a weak field of a ferromagnetic sample, demagnetized by an alternating field, leads to Rayleigh’s laws. In the case of a thermal demagnetization, the Bloch wall may be present in every well of V(x), and the domain structure is initially metastable. Considering all configurations where we can find the Bloch wall, in Néel...

In this paper, a novel intensifying-flux variable flux-leakage interior permanent magnet (IFVF-IPM) machine is proposed, in which flux barriers were designed deliberately between the adjacent poles to obtain effect and property. The rotor topology design principles of proposed are also introduced. Then, multi-objective optimization method adopted based on sensitivity analysis, some variables IF...

This study investigates partial demagnetization faults arising from stator interturn in a surface-mounted permanent-magnet-type brushless direct current motor. Because of rotor demagnetization, the fault severity increases significantly owing to an increase phase and temperature. The effect such is reflected machine parameters as motor back-EMF radial magnetic flux, which are used analyse chara...

The transport critical current Jc in a polycrystalline superconductor is a hysteretic function of applied magnetic field H0 due to flux trapping by grains. This effect has been observed by several groups and attempts have been made to calculate the intergranular field Hi as a function of the applied H0 in terms of an effective geometrical demagnetization factor D. In general a first-principles ...

Low-temperature refrigeration is of crucial importance in fundamental research of condensed matter physics, because the investigations of fascinating quantum phenomena, such as superconductivity, superfluidity, and quantum criticality, often require refrigeration down to very low temperatures. Currently, cryogenic refrigerators with (3)He gas are widely used for cooling below 1 K. However, usag...

In order to compensate the low performance of ferrite magnet, surface permanent magnet mounted (SPM) motor has considerably thicker magnet than air-gap length, thus end effect, which is determined by the ratio between magnetic air-gap and stack length, is negligible. As a result, 2-D finite element analysis (FEA), which is not possible to consider end effect, is generally used to ensure analysi...

Introduction The Advanced Photon Source (APS), as well as other third-generation synchrotron light sources, uses permanent magnets in the insertion devices to produce x-rays for scientific research [1,2]. When placed in a high-energy storage ring, these permanent magnets are subjected to irradiation from synchrotron radiation, high-energy bremsstrahlung, and bremsstrahlung-produced neutrons. Pr...