Development Of Algorithm And Program For Power System Dynamic Flow

Power flow calculation is one of the three basic calculation to analyze the power system operation status, and also the basis of short circuit and stability calculation.It’s one of the basic tools to study power grid planning and operation. With the improvement of the complexity of the power grid, all kinds of concrete and improved algorithm of power flow emerge in endlessly, mostly based on the traditional Newton-Raphon or PQ fast decoupling method.Conventional power flow assumes that the unbalance power of the system must be afforded by a balance generator. Nowadays, this algorithm for online application, especially for open circuit calculation is more and more unsuitable. This brings up the the dynamic power flow which considering the frequency adjustment working in the distribution of unbalance power. In the calculation of dynamic flow, unbalance power of the system is distributed according to the static frequency modulation characteristic of each generator or load. Introducing frequency variation into the power flow, the simulation model is closer to the real systems.This dissertation firstly intruduced the domestic and international situation of power flow and dynamic power flow, then discussed the algorithms of numerical simulation of them respectively and focused on the analysis and summary of some good algorithms.In the program, the conventional power flow not only achieves both PQ fast decoupling method and the Newton-Raphon method, but also has joined the above two methods together to solve the topic. Dispersed technique of matrix has been maken full use of when writing code, while the dynamic optimized algorithm used in numbering the nodes.Dynamic power flow is designed based on the conventional power flow in the program. In the segment of calculating the frequency, the modified Euler method is used in solving the differential equation and the frequency data is output by the integral step. Besides, the program has created interface to PSS/E and BPA data files for different requirements.Finally, some relevant examples have been used for the software testing and analysis, resulting in proving the program and the related algorithm reasonable and practical.