【作者】 李传栋；

【导师】 房大中；

【作者基本信息】 天津大学 ， 电力系统及其自动化， 2007， 博士

【摘要】 随着我国区域互联大规模电网的逐步形成,在电力系统在线动态安全分析中采用高速仿真技术以及快速稳定分析工具的需求越来越迫切。本文提出一种新型快速电力系统暂态稳定仿真方法——基于树形层次模型和双向迭代技术的电力系统暂态稳定仿真方法。该方法的研究内容主要包括电力网络划分、仿真数学模型的结构化描述、变量修正量的计算技术、整体算法流程、数值振荡的处理方法等。本文取得的主要成果如下:应用实际电网的地理区域特性以及主导节点和带权节点聚合的分区思想,提出一套比较完整的网络划分方法来实现大规模电网的划分。用树形层次结构来描述整个电力系统,考虑电力网络的分区特点,体现各种动态元件对系统动态的影响,结构化的描述电力系统的组成。提出一种基于树形层次结构的描述方法来表示电力系统的树形层次模型,介绍其实现步骤。这种描述方法具有结构化、标准化的特点。提出一种基于树形层次模型的双向迭代技术,在基于隐式梯形法和牛顿法的联立求解算法中计算变量的修正量。变量的修正量都通过“前向简化”和“后向回代”来完成。介绍了基于树形层次模型和双向迭代技术的暂态稳定仿真算法(双向迭代仿真算法)的实现流程,并研究了相应的处理数值振荡的方法。该算法在我国实际电网上计算结果与商业仿真软件BPA的计算结果进行了比较,验证了该算法的有效性。本文提出电力系统仿真新方法,具有不产生交割误差、迭代次数少,计算效率高、扩展性强、适于并行计算的特点。为电力系统在线安全稳定分析提供了有效的快速分析工具。此外,本文还对暂态稳定裕度的灵敏度计算了一些研究。基于修正能量函数和最优控制原理的变分原理提出了一种快速求取暂态稳定裕度及灵敏度的方法,并将其应用到求取电力系统的参数极限求取当中。为电力系统在线稳定分析提供了有效的快速分析工具。最后,本文对电力系统的鲁棒控制进行了一些研究。提出了一种电力系统分散保性能励磁控制器的设计方法,并将线性矩阵不等式技术和遗传算法技术结合起来构造一种综合优化方法对相应的控制器参数进行优化。更多还原

【Abstract】 With the gradual interconnection of large-scale regional power networks in China, there is an urgent need for developing new fast simulation techniques for power system on-line dynamic stability assessment (DSA). This thesis proposes a novel method for power system transient stability simulation based on the techniques of hierarchical tree model, which deal with contents of partitions among the electric power networks and describe the structure mathematical model in the simulation, bi-directional iteration, the key formulations for updating variable corrections, the algorithm schematic flow and the method for overcome oscillation phenomena in the system simulation, etc. The main results of the thesis are summarized as follows.A partition method for a large-scale power network is proposed. The partition reflects the geographical features of a large-scale power grid by incorporating the aggregation of the pivot nodes and weighted leaf nodes in a leveled-tree model. The model is thus derived in a structural construction which is well embodied in the hierarchical organization of system components and properly highlights the impact of dynamic elements on the system simulation. A standardized procedure for constructing the structural model is developed to describe the system model.To calculate the variable corrections in the iteration process using implicit trapezoidal integration method for the system simulation, a bi-directional iteration technique is proposed on the basis of the hierarchical tree model. The variable corrections of system components are computed by an approach of forward simplification and backward substitution. An algorithm is provided for complete implementation of this leveled-tree based bi-directional iteration-based the system simulation. The accuracy of the new technique of system simulation is validated by comparing the results with the well-accepted commercial software BPA.Unlike the traditionally popular partitioned solution with either explicit integration or implicit integration methods, the new simulation method is highly efficient with less iteration without interface errors. It is also suitable for adding new components for increasing new functions of simulation software and implementing in a distributed or parallel computation environment. It offers great potential for development of an on-line dynamic security analysis tool.Besides, the thesis proposes a new sensitivity approach for fast stability limit assessment. Based on the improved TEF and optimal control principle, the approach can calculate the stability margin and its sensitivity for transient stability limit analysis quickly.Finally, the thesis reports the works on robust controller design in power systems. A robust decentralized guaranteed cost excitation controller is proposed using a linear inequality technique and genetic algorithm together to tune the parameters of the controller in an optimal way. The effectiveness of the controller is demonstrated on a small-scale test power system.更多还原