永磁同步发电机电磁暂态等效建模方法及稳定性分析

嵌套同时快速求解(nested fast and simultaneous solution, NFSS)算法通过消去电路节点可以显著提高仿真速度。然而，商业仿真软件提供的永磁同步发电机(permanent magnet synchronous generator, PMSG)模型无法获取等效电路，限制了该算法在海上风电中的应用。针对上述问题，提出了PMSG电磁暂态(electro-magnetic transient, EMT)等效建模方法，并分析了建模方法的稳定性。首先，将PMSG数学模型离散化，得到用三相受控电流源表示的等效电路及接口方法，给出PMSG的控制模式和等效模型求解流程。并结合实际PMSG参数取值，分析了等效建模方法的稳定性。最后，在PSCAD/EMTDC中搭建了PMSG详细模型和等效模型进行仿真精度对比及稳定性验证，结果表明，所提模型及稳定性分析具有较好的正确性，为NFSS算法在海上风电中的应用提供了模型基础，也为发电机参数的选取提供了约束条件。

Electromagnetic transient equivalent modeling method and stability analysis of a permanent magnet synchronous generator

The nested fast and simultaneous solution (NFSS) algorithm can significantly improve the simulation speed by node-elimination in the circuit. However, the equivalent circuit of a permanent magnet synchronous generator (PMSG) model provided by commercial simulation software cannot be obtained. This limits the application of the NFSS algorithm in the simulation of an offshore wind farm (OWF). To fill this gap, this paper aims to provide an electromagnetic transient (EMT) equivalent modelling method of PMSG and analyze the stability of the modelling method. First, a mathematical model of the PMSG is discretized and thus the equivalent circuit represented by a three-phase controlled current source is obtained. Then the interface method, control mode, and equivalent solution procedure of PMSG is given. The stability of the equivalent modeling method is analyzed considering the actual PMSG parameter. Finally, a detailed model (DM) and equivalent model (EM) are built in PSCAD/EMTDC to verify accuracy and stability. The results show that the proposed model has good accuracy and that the stability analysis is correct. This provides a model basis for the application of the NFSS algorithm in OWF and constraint conditions for the parameter selection of a generator.