运行工况及磁饱和对PSS无补偿相频特性的影响分析

Effect of Operating Condition and Magnetic Saturation on PSS

本文结合PSS现场试验过程中选取特定工况开展相频特性测试,并将试验工况测试结果默认代表机组全工况特性的实际情况,据此依据Heffron-Philips模型各个参数的定义,从同步发电机运行工况及磁路饱和两个维度对机组及励磁系统的相频特性的影响开展理论分析,理论分析结果及算例均表明工况及饱和两个维度均对PSS无补偿相频特性产生影响,机组有功功率增加、进相深度加深均导致PSS无补偿滞后特性加大,迟相导致无补偿滞后相位减小,磁路饱和导致无补偿滞后相位减小;两个维度对同步发电机及励磁系统的滞后相位影响最大将达到10°。在PSS的实际应用中,应该结合机组在电网运行方式中的安排提前对工况与磁路的饱和影响加以校核,以确保实际机组PSS的功能预期。

This paper combines the phase frequency characteristic test in the PSS field test,The test results of the test working condition represent the actual situation of the full working condition characteristics of the unit by default,Based to the definition of various parameters of the Heffron-Philips model,From the influence of the phase frequency characteristics of synchronous generator and the saturation of excitation system,The theoretical analysis results and calculation examples show that both dimensions affect the uncompensated phase frequency characteristics of PSS,The increase of active power and the depth of the unit lead to the increase of uncompensated lag characteristics of PSS,The late phase causes a decrease in the uncompensated lag phase,Magnetic path saturation leads to the reduction of the uncompensated lag phase;The two dimensions will affect the lag phase of the synchronous generator and the excitation system up to 10 degrees.In the practical application of PSS,the saturation influence of working conditions and magnetic road should be checked in advance according to the arrangement of the unit in the operation mode of the power grid to ensure the function expectation of the actual unit PSS.