Performance Comparisons of Parallel Power Flow Solvers on GPU System

Abstract

This paper transforms sequential power flow problem to a parallel problem and solves it on GPU. In particular, we implement parallel Gauss-Seidel solver, Newton-Raphson solver, and P-Q decoupled solver using CUDA (Compute Unified Device Architecture) on GPU. The aim is to investigate the performance of the three different parallel power flow solvers. We use four IEEE standard power systems and one actual running power system from Shang dong Province as the test cases when comparing the speedups that a GPU system can provide. The results show that Newton-Raphson solver has the best speedup when it is operated on GPU, Gauss-Seidel solver performs the worst, and P-Q decoupled solver is in the middle. The test results also indicate that when the size of the system is small, GPU does not seem to have advantages over CPU from computation time perspective. However, as the size of the system increases, the advantages of GPU becomes more clear. For instance, when the system has close to one thousand bus counts, the GPU can provide as high as over fifty-three times speedup.