为了分析大型水轮发电机失磁过程和验证失磁保护方案 ,建立了包括水轮机、发电机、调速器和励磁调节装置在内的全系统数学模型 ,并编制了仿真软件。发电机失磁后的动态过程是比较复杂的机电过程 ,发电机组各个环节的结构和参数都将影响它的动态过程。在模拟发电机组上进行了失磁实验和仿真分析 ,实验结果验证了仿真结果的正确性。对某水电站 2 5 0MW的水轮发电机进行了失磁过程的仿真研究 ,仿真结果对工业实际有重要参考价值。 In order to analyze the demagnetization process and verify the demagnetization protection scheme of large hydroelectric generator, a whole system mathematical model including turbine, generator, governor and excitation regulating device was established and the simulation software was compiled. The dynamic process of the generator after demagnetization is a complicated electromechanical process. The structure and parameters of each link of the generator set will affect its dynamic process. Magnetron demagnetization test and simulation analysis are carried out on the simulated generator set. The experimental results verify the correctness of the simulation results. The simulation study on the demagnetization process of a 250MW hydroelectric generator in a hydropower station shows that the simulation results have important reference value for industrial practice.