基于Park模型的同步发电机参数辨识

Parameter Estimation of Synchronous Generator Based on Park Model

指出实用参数的非独立性可能导致基于实用模型的参数辨识的困难,提出直接基于Park模型辨识电路参数,必要时转换为实用参数。分析基于Park模型的同步发电机参数的可辨识性问题。对于q轴电路参数来说,其参数是唯一可辨识的。但对于d轴电路参数来说,仅利用扰动前稳态及动态过程的数据时,其参数是无穷不可辨识的;如果再利用扰动后稳态,则d轴电路参数均可唯一辨识。提出在励磁参考电压上施加阶跃扰动,先根据前后稳态条件辨识出同步发电机的部分电路参数,然后根据动态过程数据采用蚁群算法辨识其余参数。在实时数字仿真系统(real-time digital simu-lator,RTDS)上进行测试,结果表明,与采用实用模型辨识实用参数相比,该文所提方法能有效地改善参数辨识精度及其平稳性。

It was pointed that the dependency between the practical parameters of synchronous machines might lead to difficulties in estimation of the parameters. This paper proposed to estimate the circuit parameters in Park model and then convert the circuit parameters into practical parameters. The identifiability of the circuit parameters in Park model was analyzed in detail. The q-axis parameters are uniquely identifiable, the d-axis parameters are not uniquely identifiable with using the steady-state pre fault and dynamic process and uniquely identifiable with adding the steady-state post fault. An experiment was carried out via applying a step disturbance to the excitation system. Some of the circuit parameters in Park model were firstly estimated according to the steady-state equations, and others were estimated through the dynamic process with using ant colony optional （ACO） algorithm. The test results with real-time digital simulator （RTDS） show that the parameter estimation based on Park model can improve both the precision and the stability of the parameter estimation compared with the practical parameter estimation.