【作者】 孔祥实；

【导师】 任先文；

【作者基本信息】 东北电力大学 ， 电力系统及其自动化， 2012， 硕士

【摘要】 大容量、远距离输电是我国电力事业发展的客观需求，串联补偿技术是提高远距离输电系统传输容量、改善系统稳定性的一种非常有效的方法。然而，当串联补偿输电网络所形成的电气谐振回路的固有频率与汽轮发电机组轴系扭振固有频率互补（其和等于同步频率）时，系统可能发生次同步谐振，严重威胁着电力系统的稳定性和转子轴系的安全。所以近年来，次同步谐振问题已经得到了国内外科研人员的广泛关注，分析研究次同步谐振的发生机理和减小因此所带来的危害等一系列问题已然成为电力系统稳定运行的重要研究内容。本文从次同步谐振的三大问题（感应发电机效应、机电扭转作用、暂态扭矩放大现象）入手，详细阐明了其发生过程和产生的影响，并且简单介绍了高压直流输电系统的次同步振荡问题。以IEEE Frist Benchmark Model为模型，基于过零检测系统控制可控串联补偿装置的关断脉冲，以此来达到抑制次同步谐振的目的并通过仿真得到验证。由于现今解决方法还存在着种种的不足之处，本文将时滞反馈控制理论（DFC）引入电力系统保护与控制中。分别通过建立电力系统、轴系系统和时滞反馈系统的数学模型，借助于特征根聚类法分析和Routh列表分析不同串补度系统的稳定性，找出稳定的延迟时间区域。运用Simulink对稳定区域内的一个稳定点进行时域仿真验证。结果表明，运用时滞反馈控制系统可以有效的减小因次同步谐振所引起的轴系扭曲力。更多还原

【Abstract】 Large-capacity and long-distance transmission is the necessary demand of theelectric industry development of our country, and series compensation technology is aneffective way to enhance the long-distance transmission ability and the stability of thesystem. However, if the resonance frequency of series compensated transmissionnetwork and the natural frequency of turbine-generator shaft complement each other(the sum is equal to synchronous frequency), it may result in SubsynchronousResonance. It is a serious threat to the power system stability and the safety of the rotorshaft.Beginning with Subsynchronous Resonance three big problems (Inductiongenerator effect, Mechanical and electronic reverse interactions, Transient shaft torqueamplification), this paper detailed illustrates their occurrence process and influence, andsimply introduces Subsynchronous Oscillation problem of High Voltage Direct CurrentTransmission System (HVDC). This investigation is done based on the IEEE FirstBenchmark Model and shafting model. Turn-off pulse generator with zero crossingdetectors is used for Gate-Controlled Series Capacitors controlling in order to dampSSR and has been verified through the simulation.Because there are a variety of solutions of the shortcomings, this paper willintroduce delay feedback control theory (DFC) into electric power system protectionand control. Through the establishment of power system, shaft system and delayfeedback control system, the stable time delay parameter of the delayed feedbackcontroller is managed by means of employing the Cluster Treatment of CharacteristicRoots (CTCR) and Routh Listing. At last, using Simulink for a point in the stable timedomain confirm its feasibility. It shows that delayed feedback control system caneffectively decrease distortion force because of Subsynchronous Resonance.更多还原