【作者】 王小琬；

【导师】 刘光晔；

【作者基本信息】 湖南大学 ， 电气工程， 2010， 硕士

【摘要】 全国联网的实现使得机电暂态实时仿真变得更加困难。单一计算机的串行仿真难以实现这一目的,只有寄希望于并行计算。本文首先用Newton-GMRES法求解电力系统暂态稳定计算的超大规模非线性方程组。该方法的外迭代为经典牛顿法,内迭代为用GMRES法不精确求解雅可比方程。在内迭代的每步只需用有限差分替代雅可比矩阵与向量的乘积运算,从而无需显式形成雅可比矩阵,且避免了雅可比矩阵的存储,因此能大大节省计算机内存,提高计算效率。在用GMRES法求解内迭代中的线性方程组前,先用稀疏近似逆预处理法对线性方程组的系数矩阵进行预处理,以降低系数矩阵的条件数,加快GMRES迭代收敛速度。然后,本文提出了一种基于等值的机电暂态仿真并行异步新算法。其主要思想为：将原始网络分割为若干弱耦合的子系统。这些子系统在仿真的每一时步进行相互等值,各个子系统利用其他子系统传递来的等值信息进行独立迭代计算至收敛。在等值信息传递过程中,该算法使用了异步策略,即子系统在迭代计算过程中,随时监听其他子系统是否有新的等值信息传来,从而能够及时更新等值信息,加速迭代收敛。算例结果表明,该算法不仅具有较高的等值精度,而且具有较快的计算速度,已能够实现实时在线仿真计算。利用并行通信软件MPI中非阻塞通信可以将计算与通信重叠的特点实现的异步通信。本文仿真基于的硬件设施是自己建立的一个6节点的小型PC集群。本文的研究成果进一步丰富了电力系统机电暂态并行仿真计算方法,促进了电力系统机电暂态并行仿真计算的实用化进程。更多还原

【Abstract】 The implementation of a national network makes real-time electromechanical transient simulation become more difficult. It is difficult to utilize serical simulation of a single computer to achieve this object, so we can only hope parallel computing.Firstly, Newton-GMRES method is used in this paper to solve large-scale nonlinear equations of transient stability calculation of power system. The outer iteration of this method is the classical Newton method, and the inner iteration is using GMRES to solve Jacobi equations inexactly. In each inner iterative step, finite difference is used to replace the product operation of jacobian matrix and vector, so there is no need to form jacobian matrix explicitly, and avoid storing Jacobian matrix. This method can save computer memory greatly, and improve computational efficiency. Before using GMRES to solve the linear equations in the inner iteration, sparse approximate inverse method is used to precondition the coefficient matrix of the linear equations, which can reduce the conditional number of the coefficient matrix, and accelerate the convergent speed of GMRES.Secondly, a new asynchronous parallel method based on equivalence is proposed for the parallel simulation of electromechanical transient. The general idea of this method is:The network is divided into several weak-coupling subsystems. In each simulation time step, each subsystem equivalence for each other, then utilizes the equivalent information from other subsystems to calculate independently until convergence. In the transferring process of equivalent information, the asynchronous strategy is used, that subsystems monitor that there is any new equivalent information coming from other subsystems or not at any time in the iterative process of calculation, which can update the equivalent information in time and speed up the convergence of iteration. The results of samples demonstrate that the new method not only has high equivalent accurancy, but also has a fast calculation speed. For some large-scale real systems, the on-line simulation will be realized. Communication and calculation to be carried out at the same time is the character of non-blocking communication, which is utilized to realize the asynchronous communication strategy in this thesis.The simulation in this paper is based on a small 6-node PC cluster created by myself. The achievements of this thesis enrich the parallel simulation methods of power system electromechanical transient and improve the utility progress of that.更多还原