基于PMU和缓变功率的发电机组运动方程参数在线辨识  

Online parameter identification of generator motion equation based on PMU and slow-varying power

作　　者：段刚[1] 李海峰 武二克[1] 娄霄楠[1] 刘刚[1] DUAN Gang;LI Haifeng;WU Erke;LOU Xiaonan;LIU Gang(Beijing Sifang Automation Co.,Ltd.,Beijing 100085,China;State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing 210024,China)

机构地区：[1]北京四方继保自动化股份有限公司,北京100085 [2]国网江苏省电力有限公司,江苏南京210024

出　　处：《电力自动化设备》2020年第6期198-203,共6页Electric Power Automation Equipment

摘　　要：由于发电机机械功率无法被直接测量,并且电磁参数会因动态过程不同而发生较大变化,在发电机组综合参数辨识中,运动方程参数不能被准确辨识。提出了缓变功率的概念,基于相量测量装置(PMU)数据对发电机运动方程参数进行独立辨识。首先,对发电机运动方程进行变换,使得所测电磁功率由缓变功率和快变功率组成,其中缓变功率由不可测的机械功率和恒定功率组成,快变功率由待辨识的运动参数和可测得的转速组成;然后,采用低通滤波器从实测电磁功率中获取缓变功率曲线,从而将含有不可测变量的运动方程转化为以待辨识参数为未知量的可辨识方程。应用结果表明所提方法能够减少参数辨识中不考虑机械功率变化或者认为机械功率变化与转速偏差具有线性关系所引起的误差。Since the mechanical power of generator cannot be directly measured and the electromagnetic parameters vary greatly due to different dynamic processes,the parameters of the motion equation cannot be accurately identified in the integrated parameter identification of generator set.The concept of slow-varying power is proposed,and the parameters of generator motion equation are identified independently based on PMU(Phase Measurement Unit)data.Firstly,the motion equation of generator is transformed so that the measured electromagnetic power is composed of slow-varying power and fast-changing power,in which the slow-varying power is composed of unmeasurable mechanical power and constant power,and the fast-changing power is expressed by the motion parameters to be identified and the measurable rotating speed.Then,a low-pass filter is used to obtain the slow-varying power curve from the measured electromagnetic power,so as to transform the motion equation with unmeasurable variables into the identifiable equation with the parameters to be identified as the unknown quantities.The practical application results show that the proposed method can reduce the identification errors caused by not considering the variation of mechanical power in parameter identification or considering the linear relationship existing between the variation of mechanical power and the deviation of rotating speed.

关 键 词：转动惯量 阻尼系数 PMU 低通滤波 发电机 参数辨识 缓变功率 

分 类 号：TM744[电气工程—电力系统及自动化]