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电磁应力是导致笼型感应电机发生断条故障的原因之一。基于二维瞬态磁场结果，结合麦克斯韦张量法和洛仑兹力原理，对电机故障前后的转子铁心、导条所受电磁力进行计算，通过将该方法算出的转矩值与局部雅各比导数法得到的结果进行核对，并与实测电机转矩值相比较，验证了该方法的准确性。根据电机在不同断条程度时转子上各类电磁力的分布规律，得出了故障时电磁力分布的非对称性特征及应力集中位置，从磁应力的角度分析了故障电机进一步断条的可能性。计算得到的电磁力结果可作为求解转子结构形变的载荷，该文所提出的局部电磁力分析思路也可以为求解其他故障类型的电磁力问题提供参考。“,”Electromagnetic stress is one of the reasons for broken bar faults occurring in squirrel-cage induction motors. Based on the results of two-dimensional transient magnetic fields, the magnetic force around the rotor core and in the bars are calculated by the Maxwell stress method and the principle of the Lorentz force, when the motor operates before and after the failure. The accuracy of the algorithm for solving the force in this paper is confirmed through collating the torque calculated by the above-mentioned method with that obtained by the local Jacobian derivative method and comparing all the results with the experimental values. According to the results of various types of the electromagnetic force when the motor operates within different degrees of broken bar faults, the asymmetry characteristics of the distribution of the force and the stress concentration in the rotor are achieved. The possibility of further bar breaking in the motor with the broken bar fault is analyzed from the perspective of magnetic stress. The force results can be used as a load for calculating structural deformation of the rotor, and the ideas for local electromagnetic force analysis in this paper can also provide a reference for solving similar problems of the motor with other fault types.