In this paper, different curve-edged Halbach arrays in linear permanent-magnet (PM) actuators are analyzed by the open boundary differential quadrature finite-element method. In the proposed method, the open domain associated with the curve-edged PM is transformed into a finite computational domain by the scaling function; then, this finite domain is divided into several regular-shaped or irregular-shaped sub-domains; subsequently, by applying the proposed generalized blending function, the sub-domains are mapped to rectangular sub-domains, in which the differential quadrature rule is applied. Therefore, the open domain and the irregular shapes of the PMs are handled, and the magnetic field of the curve-edged PMs is solved accurately and effectively, which are validated by the Maxwell software and experiments. Moreover, design optimization is implemented to different curve-edged PM Halbach arrays, and a small thrust ripple is achieved while maintaining a large average thrust.