【作者】 李杨春；

【导师】 林济铿；

【作者基本信息】 天津大学 ， 电力系统及其自动化， 2007， 硕士

【摘要】 仿真分析方法是迄今为止进行电力系统暂态稳定性分析的众多方法中最为可靠的一种方法,如果能够实现对大规模电力系统的实时甚至是超实时仿真分析,将为系统的安全稳定运行提供有力保证;但由于机电暂态仿真的计算量很大,依据现有的条件,要对联网电力系统的暂态过程进行实时仿真还存在相当的难度。而随着分布式并行处理技术的发展,尤其是可扩展、高性价比的PC集群的出现,为这个目标的实现带来了希望。本文的主要工作如下:首先研究了基于预处理共轭梯度法的电力系统暂态稳定仿真计算方法,提出了一种与矩阵方程直接解法相结合的预处理共轭梯度混合新算法。该方法首先结合不完全LU分解对暂态稳定计算中的雅可比矩阵进行预处理,来减少计算量;其次,通过利用电力系统暂态稳定性仿真的特点-相隔几个积分时步系统的状态变量相差不大,充分利用已有的雅可比矩阵和预处理结果,并和直接法相结合,进一步提高迭代求解的计算速度;在此基础上,对该方法与直接法在不同系统规模下的计算量进行了分析和比较。然后简要介绍了消息传递接口(MPI)的基本概念,对本文基于波形松弛的并行算法中采用的点对点通信和组通信等消息传递模式进行了分析。最后对基于波形松弛的电力系统暂态稳定分析的并行仿真策略和仿真算法进行了研究,提出了一种新颖的并行算法:按照系统各部分的地理分区将其划分为多个子系统,对通过联络线及边界节点互联的子系统进行等值,从而获得相邻子系统对本子系统的影响;进一步将移置到边界处的子系统等值电流作为子系统间交互的波形信息,从而实现互联子系统之间的解耦和并行松弛求解。在PC集群上的计算结果表明,该算法有比较高的并行加速比和计算效率,在无任何加速措施的情况下,对于较大规模的系统已达到了在线实时仿真计算的要求。更多还原

【Abstract】 Heretofore, time domain simulation is the most reliable method for power system transient stability analysis. The On-line real-time or the over real-time time domain simulation for the large-scale power system, providing a favorable and well-knit base for the system to operate securely and stably, but still could not be realized because of the huge computational quantity of electromechanical transient stability at present time. However, with the development of distributed parallel processing technology, especially the emergence of extensible and high cost performance PC-Cluster platform brings a hope for this problem to be solved.The main work of this thesis is as follows:Firstly, the simulation method of Power systems transient stability which based on Preconditioned Conjugate Gradient (PCG) is studied. A new algorithm which combines direct method and PCG method is presented. The method adopts incomplete LU factorization to precondition on the jacobian matrix in order to reduce the computation quantity; and then utilizes the characteristic of Transient Stability simulation which in several simulation step the system state variables changs little, to reuse the jacobian matrix and its preconditioned result of the pre-step for subsequent simulation step; and further combines with direct method to speed up the iterative solving process. And the computation quantities of the algorithm and the direct method are done and compared.And then the basic concept of MPI is introduced in brief. Two communication types of MPI namely point to point communication and collective communication which are adopted in this thesis are described in detail.At last, a new parallel strategy and algorithm for power system transient stability analysis based on waveform relaxation method is presented. The process is: the network is divided into several subsystems based on its geography subareas; the neighbour subsystems foreach subsystem are being equivalence processed to the tie lines and boundary buses; further, the equivalence currents transferred to the boundary buses of the relevant subsystems are considered to be the communication waveform information between the subsystems, and the boundary buses are treated as the voltage source; then the subsystems are naturally decoupled from each other, and the parallel calculation is finally realized. The result of the practical sample on the PC-Cluster system demonstrates that the new algorithm possesses high calculation efficiency and parallel speedup ratio, and can achieve on-line calculation for large-scale systems without any speedup measure.更多还原