Performance evaluation of a hybrid of public and private Smart Grid wireless access networks

The most challenging issue in Smart Grid (SG) communications is the management of a vast amount of SG communications traffic in the wireless access network, which connects power substations to a large number of SG devices. To confront this challenge, electric utilities and telecommunications operators have proposed the use of a hybrid wireless access network, referred to as a hybrid SG network, which is a combination of both public and private access networks. The public access network is leased by the electric utility from a telecommunications operator, where the network carries both Human-to-Human (H2H) communications traffic and SG communications traffic. On the contrary, the private access network is owned by the electric utility to exclusively deliver the SG communications traffic. However, a key issue in hybrid SG networks is how to efficiently partition the SG traffic onto public and private access networks. In this paper, we propose a unified analytical framework, based on a queuing system, to evaluate the performance of hybrid SG networks under different policies for the partitioning of the SG traffic. By using this framework, expressions for several performance metrics are derived and used to compare between two basic partitioning policies, referred to as load-based and traffic-based. The analytical framework is validated by simulations of a wireless network model using real-world SG traffic profiles from the Ausgrid Smart Grid Smart City project and shown to agree well with the simulations.