Research On Tree Structure Based Power Flow Parallel Calculation Of Power System

At present, with the increasing of power system's scale in China, it requires a higher speed on the reasearch of power system static stability and transient stability simulation. The paralle computing, based on the network partition, is an effective method to enhance the simulation speed of large-scale power grid. It breaks the bottleneck of difficulty to greatly enhance the simulation speed in traditional algorithm. This paper presents a power flow parallel algorithm based on the calculation of tree structure.Based on Newton-Raphson algorithm, it is a kind of space parallel algorithm. After the network partition, Jacobian matrix of each partition can be formed separately, which reduces the dimension of Jacobian matrix. And then the high-dimensional linear equation will be solved as a correction equation whose dimension and complexity has been greatly reduced. As it costs the most time to solve the correction equation in power flow calculation, this algorithm can greatly reduce the time. Because of the tree structure, the different nodes' power filow at the same layer can be calculated independently. The correction equations of each partition are linearly transformed. And their linear expressions are sent to the root node for simultaneous. Since there is no similar process, the result of each iteration is exactly the same as before. So it is convenient to use distributed computing and easier to implement with the stronger modularity and scalability. It can also be applied to the real-time and super-real-time simulation of power systems.A parallel power flow program is coded. The results are compared to the traditional serial Intel MKL program on Newengland system, Shanxi Province and Northeast China Power Grid, which indicates the running time is greatly reduced, and its convergence and accuracy are not decreased at all.