FluxMerge Reduces Air Gap Magnetic Flux Leakage

FluxMerge is one of the first emerging technologies that reduce air gap magnetic flux leakage in the magnetic circuit path of all electric machines. FluxMerge achieves this by adjusting the magnetic reluctance distribution of the pole faces across an air gap, using microstructures placed on the pole faces. The microstructures cause the magnetic flux crossing over the air gap to merge toward the central axis of the magnetic circuit path, resulting in reduced leakage into the surrounding space. The shape and distribution of the microstructures on the pole faces governs the merging of the magnetic flux.

FluxMerge is easy and inexpensive to implement, because it requires no configuration change to the machine and the microstructures can be formed using simple molding techniques. Motors equipped with FluxMerge realize an average efficiency improvement of 1.5 percent. Given the vast number of motors and their power consumption, FluxMerge is capable of significant carbon reduction. ITRI considers FluxMerge an innovation comparable to the emergence of power electronic motor drives in the 1970s and the series of rare-earth permanent magnet material developments starting in the 1950s.

Flux leakage is inevitable and reduces the efficiency of all electromagnetic machines that include an air gap in their circuit. While FluxMerge applies to all such machines, ITRI considers its main applications to be motors and generators. Flux leakage reduces the motive power of motors, which forces design compensations in increased size, weight, and electrical power consumption to achieve their purpose. Flux leakage in generators reduces the amount of mechanical power converted to electricity.

By reducing air gap leakage, FluxMerge improves electric machine performance and torque across the air gap. As a result, designers can decide whether to maintain the power rating in a smaller, lighter machine that is less costly to produce, or to deliver more power in the machine’s current form, or a combination of these advantages. For example, a stair lifter equipped with FluxMerge features a quieter motor, energy savings, more rounds per charge, and the ability to carry more weight.

Other techniques for electric-machine efficiency improvement such as rare-earth magnet strength enhancement, optimization of stator and rotor structural configurations, and power electronic controller firing schemes are specific only to some electric machines. FluxMerge reduces air gap magnetic flux leakage for all electric machines in addition to the improvements from the above techniques.

FluxMerge is available now for licensing by electronics and motor companies.