Hierarchical Parallel Solution on a Multi-Core Cluster for Power System Simulation

Abstract

Multi-core CPU is widely used for PC now. PC cluster, which is composed of many PC's, can easily get its high performance using multi-core CPU's. It is named as a multi-core cluster. In this paper, we propose hierarchical parallel solution methods of power system transient stability analysis on a multi-core cluster.
In a multi-core cluster, there are two level layers in communication system. One is the communication among cores in a CPU, and the other is the communication among CPU's in the multi-core cluster. To communicate between cores in a CPU, there are two ways. One is the communication through cache, and the other is the communication through bus in a CPU. The speed of the former one through cache is higher than that through bus. In addition, to get maximum speed of communication through cache, the size of data to process should be kept within the size of each cache used in each calculation step. A long development term is necessary to optimize software for two communication ways. We developed an optimization technique of matrix operations and a hierarchical parallel processing method for a multi-core cluster, and applied them to solve differential equations and simultaneous equations in power system simulation. We obtained 1.5 times speedup using two cores in a PC, which communicate through shared memory and 1.39 times speedup using two PCs with single core which communicate through bus.