Flux‐Switching Machines

Abstract

Flux‐switching machines are a type of brushless machines with a doubly salient structure, which has excitation sources, for example, permanent magnets (PMs) and/or field‐excited windings, and armature windings on the stator, and no magnets or windings on the rotor. The flux‐switching machines have the advantages of high torque (power) density, large torque output capability, high efficiency, strong irreversible demagnetization withstand capability, good thermal dissipation and liquid cooling conditions, and favorable high‐speed operation. These advantages are particularly important for electric propulsion systems, such as electric vehicles and hybrid electric vehicles, and electric ships and airplanes. According to the excitation modes, there are three types of flux‐switching machines: permanent magnet flux‐switching (PMFS) machines, hybrid‐excited flux‐switching (HEFS) machines, and wound‐excited flux‐switching (WEFS) machines. This article presents topologies, operation principles, electromagnetic performance, and applications of flux‐switching machines. In addition, different topologies of stator and rotor are also discussed.

Design Optimisation and Performance Evaluation of Flux Switching Machines for Geared Medium-Speed Wind Generator Drives

“…Thus, they result in less cumbersome rotor structures as depicted in Fig. 1 An overview on these stator-active PM machines is already provided in Hua et al (1999) [43] and Cheng et al (2011) [44], hence the researcher is not going to go on and on about it. In Hua et al (1999) [43], it was simply about PM-FSMs--their features and what makes them interesting for a number of application needs; their different excitation modes such as PM-FSMs (only PMs), WF-FSMs (only wound-fields) and HE-FSMs for hybrid-excited systems (both PMs and wound-fields); their electromagnetic performance; as well as their different stator and rotor topologies.…”

Performance comparison between rotor flux-switching and stator flux-switching machines considering local demagnetization

“…However, it worth noting that the armature slot areas are significantly reduced due to the co-existence of PMs and armature windings in stator, which results in a degraded torque density. 2 In addition, since the PMs are wound around by the concentrated windings, the winding heat transfers to the PMs directly resulting in a decreased PM remanence B r (T) and an increased PM knee point B knee (T), and then the irreversible demagnetization may be generated. 3 As is well known, PM demagnetization will cause performance degradation and even safety issue of PM machines, hence, it is necessary to evaluate the demagnetization behaviors.…”

Improved electromagnetic models with saliency effect, a novel canned switched reluctance machine drive as example

“…Magnetic saturation is conventionally modeled by magnetic equivalent circuit (MEC) with compromise between computational cost and accuracy. [27][28][29][30][31] In the network, each pole is lumped by a magnetic reluctance. However, such method is less accurate on SRMs.…”