Hybrid adaptive framework for coordinated control of distributed generators in cyber-physical energy systems

Abstract

With the development of information and communications technology (ICT) and inundation of sensing devices, the control of smart grid is undergoing a paradigm shift from centralised/decentralised to a more distributed nature allowing each distributed generator to receive information from sensors at distant buses. In such systems, there is much interdependency between various power, control and communication parameters due to which the control of parameters from one domain gets affected by other. The central idea of this study is to develop a generic, hybrid and customised framework to jointly model the multi-disciplinary variables and their interactions present in the smart grid and to develop controllers in an adaptive manner to ensure better control of physical variables such as voltage irrespective of the changes in operating point brought about by changes in physical/cyber parameters. Hence, the different operating conditions of the power system have been modelled as multiple subsystems of a hybrid switching system and controller design is carried out by solving the optimisation formulations developed for delay-free and delay-existent cases using the theory of common Lyapunov function. The optimisation is carried out using the block coordinate descent methodology by converting the non-convex formulation into a series of convex problems to obtain a solution.

Keywords

• distributed power generation
• Lyapunov methods
• concave programming
• convex programming
• smart power grids
• hybrid adaptive framework
• coordinated control
• distributed generators
• cyber-physical energy systems
• ICT technology
• smart grid
• hybrid switching system and controller design
• optimisation formulations
• Lyapunov function
• non-convex formulation
• convex problems
• block coordinate descent methodology
• delay-existent cases
• delay-free cases