电压不平衡条件下电厂发电机转子过电压状态智能监测  

Intelligent Monitoring of Overvoltage Status of Power Plant Generator Rotor Under Voltage Imbalance Conditions

作　　者：李书硕 王睿东 尚志强 胡永哲 于艳华 LI Shushuo;WANG Ruidong;SHANG Zhiqiang;HU Yongzhe;YU Yanhua(Inner Mongolia Daban Power Generation Co.,LTD.,Chifeng Inner Mongolia 025150,China)

机构地区：[1]内蒙古大板发电有限责任公司,内蒙古赤峰025150

出　　处：《微电机》2025年第3期22-26,50,共6页Micromotors

摘　　要：为降低多种故障因素导致的电压不平衡条件对电厂发电机稳定运行的影响,提出电压不平衡条件下电厂发电机转子过电压状态智能监测方法。鉴于电压不平衡条件下电厂发电机转子电流、有、无功功率和电磁转矩会产生二倍频波,选取具有代表性的发电机转子电流为分析变量,通过在发电机转子回路中安装的电流传感器,实时采集发电机转子电流,采用希尔伯特-黄变换方法,以转子电流信号为经验模态分解的输入,得到若干固有模态函数,再利用希尔伯特变换从中得到瞬时频率幅值谱,作为过电压状态监测的特征量,通过极限学习机完成转子过电压智能监测。实验结果显示:该方法可以有效提取发电机转子电流的瞬时频率特征,并实现多种故障导致电压不平衡条件下的发电机转子过电压状态监测。To reduce the impact of voltage imbalance caused by various fault factors on the stable operation of power plant generators,an intelligent monitoring method for rotor overvoltage status of power plant generators under voltage imbalance conditions was proposed.Given that the rotor current,active and reactive power,and electromagnetic torque of power plant generators under voltage imbalance conditions will generate second harmonic waves,a representative generator rotor current was selected as the analysis variable.By installing a current sensor in the generator rotor circuit,the rotor current of the generator was collected in real time.The Hilbert Huang transform method was used,and the rotor current signal was used as the input for empirical mode decomposition to obtain several intrinsic mode functions.Then,the Hilbert transform was used to obtain the instantaneous frequency amplitude spectrum as the characteristic quantity for overvoltage state monitoring.The intelligent monitoring of rotor overvoltage was completed through a limit learning machine.The experimental results show that this method can effectively extract the instantaneous frequency characteristics of the generator rotor current and achieve the monitoring of the generator rotor overvoltage state under various voltage imbalance conditions caused by faults.

关 键 词：电压不平衡 发电机转子 过电压 状态监测 转子电流 希尔伯特-黄变换 

分 类 号：TM315[电气工程—电机]