Novel Bent Steel Sheet Strip Based Two-Pole Single-Phase BLDC Motor Topology for Low-Cost Fan Applications

Motor drive cost reduction is essential for high-volume production of automotive sub-fractional horsepower brushless direct current (BLDC) motor applications (e.g., LED headlight fans, seat ventilation, sensor blowers). Aiming to reduce cost, complexity, and component count, this paper proposes a novel low-cost single-phase two-pole outer-rotor BLDC motor topology for fan applications, based on one or two bent steel sheet strip(s) instead of a more expensive lamination stack. The motor’s structure and working principle are explained in detail and, for a proof of concept, investigations in the no-load and load conditions are performed using finite-element analyses as well as back-EMF measurements. In addition, important design considerations are discussed. The findings confirm the practicality of the proposed low-cost motor topology.