Driving Characteristics of X-Y Linear Induction Motor with Two-dimensional Primary Winding

In the linear induction motor (LIM), the secondary can move in two directions (X and Y) by placing the primary coils twodimensionally. When these coils are excited in the direction of 45 electrical degree, the secondary moves to the direction, which is determined by the pole pitches of both directions and the load condition. In this paper, we propose a new type of winding scheme composed of four groups of primary exciting coils, which are shifted n/2 spatially in both directions. These coils are energized by twophase supply with independent phase shifters. By using this winding scheme, all sides of the primary coils contribute to the secondary movement. Next, we compare the proposed winding scheme with another one using two kinds of independent exciting coils in both directions. The feature of the former is driven by a traveling magnetic field with constant amplitude when the primary coils are excited in the direction of 45 electrical degree, while the latter is simple in construction of the primary coils. We first made both of flat type X-Y LIMB with the proposed winding scheme and with a normal one. And then, we analyzed the magnetic fields in the air-gap of these motors by the three-dimensional finite element analysis based on A-ϕ method, and compared the results with experimental ones. Finally, we apply the motor with the proposed winding scheme to a branch apparatus.