【作者】 张雪焱；

【导师】 黄少锋；

【作者基本信息】 华北电力大学（北京） ， 电力系统及其自动化， 2010， 博士

【摘要】 现代互联电力系统的复杂程度不断增加。近年来国内外发生的多起大停电事故表明,保证电力系统安全稳定运行的难度正在逐渐加大。缺乏快速、有效、适应性强的稳定控制方法是引发大停电事故的重要原因之一。广域同步测量系统在电力系统的逐渐普及,为暂态稳定分析和控制研究提供了新的契机。本论文从WAMS实测数据出发,研究了提高电力系统稳定性的全局综合控制、闭环紧急控制及解列控制等多种控制措施。论文的主要工作如下：1)提出一种暂态稳定闭环紧急控制方案。提出将开环控制与闭环控制两种方式相结合,扩大了紧急控制的保护范围。分析了稳定性预测过程中电磁功率突变产生的原因及其影响,并提出了计算修正的方法。分析了闭环控制模型和测量过程产生的误差,提出采用校正系数进行补偿,保证控制的有效性。最后,提出了完整的闭环紧急控制方案。根据闭环控制过程中不同阶段的特点,分别采用轨迹外推和数值仿真方法进行受扰轨迹预测。所提控制方案能够有效的提高系统的暂态稳定性。2)提出一种多机系统下的可控制动电阻协调控制方法。以各发电机制动电阻吸收功率组成的向量作为控制量,对多机系统中的TCBR控制器建立数学模型。建立优化模型,并求取非线性最优反馈控制规律,实现TCBR之间的最优协调控制。采用如下方法求取非线性最优反馈控制规律：首先求出作为共态变量和状态变量函数的开环最优控制,然后利用共态变量和状态变量之间的非线性关系,消去共态变量,就得到作为状态变量的函数的最优反馈控制律。3)提出一种励磁与可动制动电阻相协调的全局综合控制器。控制器采用两层控制结构。下层的每个子系统对TCBR进行闭环反馈控制,而上层的协调控制器利用广域同步信息处理各子系统之间的非线性关联量,不断为各子系统提供优化向量,确保整体控制性能的最优化。所提方案将本地控制信号与WAMS提供的全局控制信号相结合,可有效提高对于大干扰和小扰动的控制效果。4)提出一种基于WAMS的自适应解列方法。自适应解列首先采用EEAC法判断失步机群,然后采用最小潮流断面法寻找系统最佳解列断面。最小潮流断面法按照如下原则寻找解列断面：每个子系统各自保持同步运行；解列后各子系统的发电功率与负荷功率能够基本平衡。研究了将解列作为与切机等并列的紧急控制措施在第二道防线中所起的作用。更多还原

【Abstract】 The increasing of the complicity of modern inter-connecting power system often makes solving a actual problem difficult when traditional analysis and control strategy are used. Several large scale blackouts happened both domestic and abroad approve that ensuring securely and the stable operation of power systems are becoming more and more difficult. One of the most important reasons of blackout is the lacking of fast, effective and adaptive control method for improving stability. The widespread application of Wide Area Measurement System (WAMS) provides a new momentum for the research of the analysis and control of power system transient stability.Based on WAMS signal, wide area coordinating control, closed-loop emergency control and islanding control for improving transient stability of power systems are researched in this thesis. The main works of this thesis are:1) A closed-loop emergency control scheme to enhance transient stability of power system using WAMS information is proposed. The proposed method combined the open-loop control and the closed-loop control, resulting in extending the protect area of emergency control. The reasons and the influence of sudden change of the electric power of generators during stability prediction are analyzed. Moreover, corresponding correction method is proposed. The error existed in closed-loop control modal and measuring are analyzed and corrected in order to guarantee the effectiveness of control method. Last, a complete solution of closed-loop emergency control is proposed. Different perturbed trajectory prediction method are applied during the control course. Simulation results approve that the proposed control scheme can improving transient stability of power systems effectively.2) A coordinated control method of Thyristor Controlled Braking Resistor (TCBR) for multi-machine system is proposed. The basic structure and mathematic model of TCBR controller of multi-machine system is researched. Moreover, nonlinear optimizing control is adopted according to three level co-state prediction algorithm. The optimal mathematic modal is proposed, and the nonlinear optimizing feedback control law is acquired. The proposed controller can greatly improve transient stability of the power system. Simulation tests on a 4-machine system show the effectiveness of the proposed method.3) A global control scheme for improving transient stability of power systems by combining exciter and thyristor controlled braking resistor is proposed. The control structure is organized into a two-layer controller by applying hierarchical control strategy of large-scale system principle. The lower layer is composed of decentralized local feedback controllers, each of which takes local feedback signal and controls its connected generator. In the upper layer a global controller is designed to enhance the effectiveness of decentralized local controllers. The global controller coordinates local controllers by generating remote feedback signals which ensuring the global optimal solution of the overall system transient performance. The proposed control scheme can guarantee fast and accurate control actions of local controllers when a power system is subjected to large disturbances. Simulation results show the effectiveness of the proposed control scheme.4) A adaptive islanding method based on WAMS is proposed. First, none synchronizing group of generators is recognized by EEAC method. Moreover, the optimal islanding surface is found by applying minimal power flow surface method. Furthermore, the effect of islanding control as a emergency control method in the second defense line is analyzed.更多还原