Security, trust, and QoS in next-generation control and communication for large power systems

The present communication architecture supporting control of the electric power grid makes it difficult to use the wealth of data collected at high rates in substations, retarding their use in new applications for controlling the grid. A flexible, real-time data network would make it possible to use these data for many more control and protection applications, potentially increasing the grid's reliability and increasing its operating efficiency. Applications that could use these data include: decentralised load frequency control; closed-loop voltage control; transient and small-signal stabilisation; and special protection schemes using data gathered over a wide area. Such applications and the flexibility of the underlying communication network imply greater data sharing between utilities, leading to new performance, availability and reliability requirements. This paper examines the security, trust and Quality of Service (QoS) requirements imposed by these applications and shows how they are met by mechanisms included in the GridStat middleware framework that we are developing.