In order to solve the problem of how to maximize the electromagnetic force when the appearance of the electromagnet is the same,the existing design ideas of the electromagnet were applied to the design of cylindrical electromagnets,and an improved hybrid particle swarm optimization (PSO) method was used to optimize the internal structural parameters of the electromagnet.Equivalent magnetic circuit method was used to deduce the mathematical model of the electromagnet,and Maxwell finite element simulation was used to verify its accuracy.Then,a single-objective optimization method was used to obtain the parameters affecting the electromagnetic force.Finally,improved particle swarm optimization algorithm was used to carry out multi-objective optimization and the optimized parameter values were obtained.Several groups of optimization data show that the electromagnetic force in the effective working area obtained by the multi-objective optimization method is larger.The simulation results show that the electromagnetic force after optimization is improved by 20%,which proves that the optimization method is effective.