Abstract <p>The <i>d</i>-axis inductance (<i>L</i>_<i>d</i>) of the negative-salient permanent magnet synchronous motor (NSPMSM) is larger than the <i>q</i>-axis inductance (<i>L</i>_<i>q</i>). Compared with the traditional positive-salient permanent magnet synchronous motor (PSPMSM), the NSPMSM has the characteristics of wide constant-power speed range, strong overload capacity and the permanent magnet is not easy to demagnetize. In this paper, a new type of NSPMSM is proposed by using magnetic bridge to increase the <i>L</i>_<i>d</i> and W-type permanent magnet to decrease the <i>L</i>_<i>q</i>. Firstly, according to the working principle of the NSPMSM, a new motor structure is proposed, and the equivalent magnetic circuit of the new motor is established. Secondly, the combination of single objective optimization and multi-objective optimization is proposed. The influence of design variables on the optimization objective is measured by sensitivity index, and then the optimal model of motor is obtained by response surface method. Finally, finite element analysis is used to compare the performance of the new motor and the traditional motor. The NSPMSM constant-power speed reaches three times of rated speed. The theoretical analysis results are consistent with the simulation results, and the effectiveness and feasibility of the new type of motor are verified.</p>