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Foster-Miller is experienced in the research & development, analysis, design, construction, and control of many different types of electro-magnetics and electric machines. Our research & development of electro-magnetics and electric machines projects have run the gamut from tiny custom voice coil actuators powered by AA batteries, to self-excited induction generators, to enormous linear induction motors used to launch jet fighters from aircraft carriers. Specific electric machine-related technologies that Foster-Miller addresses include finite element analysis, linear motors, maglev and servo controls. The Foster-Miller research & development team produced one of the winning electro-magnetics maglev concepts in the early 1990’s and further research & development of electro-magnetics in this area led to our design of a “maglifter,” system to launch rockets into outer space. Foster-Miller specializes in the research & development of finite element modeling of electromagnetic devices and electric machines. In addition to working with existing commercial codes, we create new programs that address novel situations that are not well represented by existing codes. We are also skilled in creating semi-analytical models of magnetic devices that allow the results from finite element analysis to be incorporated into more streamlined forms that are suitable for dynamic simulation and controller design. Foster-Miller is also the exclusive commercial source of support for the general-purpose 2D/Axisymmetric magnetic finite element package, FEMM (seefemm.foster-miller.net). This package is widely used by thousands of scientists and engineers all over the world to tackle a variety of problems ranging from the design of motors, actuators and speakers to the analysis of particle accelerators, magnetic nanoparticle interactions and bioelectromagnetics. FEMM is also an integral part of the electric machine design curriculum at many universities. Over the past five years, Foster-Miller has successfully completed more than $13 million of work involving the analysis, design, construction, and control of large prototype linear motors. These motors are generally intended for high-speed, high-performance applications such as launching or arresting aircraft. In the launching and arresting applications, the motor must supply a very high transient force, and the motor must be carefully controlled so that the trajectory of the aircraft closely tracks a predetermined position/velocity profile. We have developed new strategies to meet these unusual requirements. We have devised motor topologies and control schemes to perform these tasks. For example, we created a "slotless" long-stator linear induction motor design that allows for much higher shear pressures than are possible with more traditional designs. We have also created generalized versions of field-oriented control that accommodate the peculiarities of highly redundant linear motors versus typical rotating machines Foster-Miller is a national leader in the field of magnetic levitation, or "maglev." We led one of the four teams that developed Maglev System Concept Definitions under the National Maglev Initiative in the 1990s. More recently, we have applied electrodynamic suspension maglev technology to high-speed applications for the Air Force and NASA. These projects involved the analysis of three-dimensional magnetic fields with motion induced eddy currents using both analytical and numerical methods, as well as the design and fabrication of prototype hardware. Many of the electric machine applications at Foster-Miller require closed-loop control to achieve high performance specifications. We have produced a number of control systems for linear motors. For example, our Advanced Linear Motor (ALM) prototype hardware successfully demonstrated accurate closed-loop tracking of a commanded position trajectory that peaked at approximately 140 mph over a 42-foot run out. Our linear motor controllers typically use field-oriented control methods to achieve their high performance. The unique features of the applications we consider necessitate innovative extensions to the methods used in rotating machines, both in motor control algorithms and in hardware design.
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