Application of In-Memory Database in Concurrent Topology Analysis of GIS Systems for Large-Scale Distribution Power Grids

Geographic Information System (GIS) is the basic data management and visualization platform for transmission and distribution power network planning, operation scheduling and repair decision support systems. GIS systems based on SQL database can’t meet the real-time requirements of massive data processing and large-scale concurrent topology analysis of distribution networks. An object-oriented in-memory database is introduced, which uses partitioning and paging storage technology for efficient caching and retrieval of large-scale grid topology models. Parallel processing techniques based on data partitions and task scheduling queues are developed, which enables the parallel executions of multi-user requests of topology tracing(reading) and switch open-close operations(writing). Further, for the conflicting write requests across partitions, a parent-child task queue is introduced. In the stress test of the on-line system of a provincial company with more than 10 million power grid equipment, response time less than 0.2 seconds is observed, under the load of more than 400 topology analysis requests per second per server.