电力系统超低频频率振荡分析及扰动源定位  

Ultra-low Frequency Oscillation Analysis and Location in Power System

作　　者：李莹 富亚洲 王官宏 王东阳 艾东平 李文锋 LI Ying;FU Yazhou;WANG Guanhong;WANG Dongyang;AI Dongping;LI Wenfeng(China Electric Power Research Institute,Haidian District,Beijing 100192,China;Beijing ABB High Voltage Switchgear Co.,Ltd.,Tongzhou District,Beijing 100079,China)

机构地区：[1]中国电力科学研究院有限公司,北京市海淀区100192 [2]北京ABB高压开关设备有限公司,北京市通州区100079

出　　处：《电网技术》2023年第5期1770-1779,共10页Power System Technology

摘　　要：超低频率振荡是高比例水电系统面临的突出挑战,大量水电机组调速系统及水力系统的负阻尼聚合是激发全网频率振荡的主要原因。频率振荡期间,水轮机接力器往复动作会导致液压系统油压下降,严重时将导致机组低油压而停机,负阻尼振荡将导致系统频率增幅振荡,控制不及时可能触碰系统高/低周控制动作。传统的降低机组有功出力、提高系统电压水平等振荡控制手段对超低频频率振荡抑制没有明显效果,这对系统安全稳定运行带来严重危害。为准确定位超低频振荡强相关机组,提出了利用发电机速度偏差与机械功率获取调速系统振荡能量的计算方法。同时,针对工程中发电机机械功率难以直接测量的难题,研究提出了利用广域测量系统(wide area measurement system,WAMS)实测的发电机转速和电磁功率合成发电机机械功率的实用算法,可准确计算动态过程中发电机机械功率值,并在电网超低频频率振荡案例分析和大电网超低频振荡预控中验证了该实用算法的有效性。该方法可综合应用同步相量测量装置(phasor measurement unit,PMU)/故障录波/WAMS等广域信息,实现电力系统发生超低频振荡时,可对机组控制设备进行精细化定位,对发电机控制系统性能进行准确探察评估,从而对大电网频率振荡形态和机组动态行为进行全景式感知监测,为电网安全稳定运行构筑坚强的安全屏障。Ultra-low frequency oscillation is an urgent challenge accompanied by a high proportional hydropower system.The negative damping aggregation of the hydropower unit speed regulation system and the hydraulic system is the main cause of the oscillations,which stimulates the ultra-low frequency negative damping oscillations of the whole network frequency.During the frequency oscillation,the reciprocating action of the hydraulic turbine servomotor can lead to a decrease in the oil pressure of the hydraulic system.In severe cases,the unit will be shut down due to low oil pressure.Negative damping oscillation will lead to an oscillation of the system frequency increase,and untimely control may touch the high/low cycle control action of the system.The traditional oscillation control methods such as reducing the active power output of the unit and improving the system voltage level have no obvious effect on suppressing ultra-low frequency oscillations,which poses serious harm to the safe and stable operation of the system.In order to accurately locate ultra-low frequency oscillation strongly correlated units,this paper proposes a calculation method for obtaining the oscillation energy of the speed governing system using the generator speed deviation and mechanical power.In order to accurately locate ultra-low frequency oscillation strongly correlated units,this paper proposes a calculation method for obtaining the oscillation energy of the speed governing system using the generator speed deviation and mechanical power.At the same time,aiming at the difficulty of directly measuring the mechanical power of the generator in engineering,a practical algorithm for synthesizing the mechanical power of the generator using the measured generator speed and electromagnetic power from the Wide Area Measurement System(WAMS)is studied and proposed,The utility model can accurately calculate the mechanical power value of the generator in the dynamic process,and verify the effectiveness of the practical algorithm in the case analysis of u

关 键 词：超低频振荡 调速系统 振荡能量 力矩分解 扰动源定位 

分 类 号：TM21[一般工业技术—材料科学与工程]