Solar Plane Propulsion Motors With Precompressed Aluminum Stator Windings

Abstract

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Design of a brushless PM starter-generator for low-cost manufacture and a high-aspect-ratio mechanical space envelope

“…Hence, a modular radial-flux machine topology with an openslot stator and a preformed winding construction has been selected here. The preformed and/or compressed concentrated winding topology allows for the coils to be manufactured in isolation, in a simple and repeatable manner providing improved winding performance measures and manufacturability, as compared with other winding topologies [6], [8], [9], [12], [15], [25]. The preformed coils are then placed in the stator slots with an appropriate slot liner and secured with a slot wedge.…”

“…The 'design for cost' and 'design for manufacture' paradigms have gained increasing interest, which is reflected in the available literature [1]- [12]. In particular, research into machine designs with reduced quantities of rare-earth PM materials achieved through the adoption of interior PM machine topologies or the use of alternative PM materials such as ferrites, Dysprosiumfree or Dysprosium-less NdFeB.…”

“…Furthermore, PM-free designs such as reluctance and synchronous reluctance machine topologies have received considerable attention [1]- [5]. The development of low-cost stator and winding topologies have been reported which allow for ease of manufacture and assembly while providing the required performance measures such as good heat extraction from the winding assembly and reduced winding power loss [6]- [12].…”

Synchronous reluctance motor technology: industrial opportunities, challenges and future direction

“…This machine has been shown to exhibit high torque density and higher efficiency for the same 18 frame size compared to both the induction motor and the conventionally wound synchronous reluctance machine [26,27,28]. The main benefits of adopting this cSynRM topology of machine are as follows; At an initial glance, the topology appears to be very desirable, the short end winding due to their short span now contain less copper and do not overlap other phases, aiding electrical isolation and neat coils to be wound -effectively enabling higher slot fill factors, upwards 80% in some cases when compressed coils are utilized [31]. However, there are associated drawbacks of selecting this topology.…”

Design of a synchronous reluctance motor with non-overlapping fractional-slot concentrated windings

“…A very short axial length (along shaft centre axis) of the end windings was achieved, only 19mm. A fill factor of approximately 60% was achieved, however recent work has shown that much high fills are possible [13] if the coils are precompressed. The rotor component was electro-discharge machined, a stator lamination is shown in Figure. 13.…”