Abstract：A structure of permanent magnet (PM) ironless linear motor is presented. For the comparative research one Halbach array prototype and one radial array prototype with same size are made. The magnetic field of Halbach array and radial array is analyzed. The decoupled electromagnetic force equations are proposed. The static thrust force, back-EMF and positioning characteristics of two prototypes are studied experimentally. Compared with the radial array prototype, the thrust force constant of the Halbach array prototype increase by 1.37 times, the back-EMF amplitude increase by 1.5 times with better sinusoidal waveform, and the control current amplitude decrease 1.4 times when same dynamic performances are obtained. Theoretical and experimental results show Halbach array can strengthen the air-gap flux density and improve magnetic field sinusoidal distribution.
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2010, Vol. 25 
