Integration of distributed renewable energy into existing networks

At this current time, the Australian electricity network faces a potential death-spiral event which could trigger trigger mass exodus of the customer base, driven by positive feedback from increasing retail prices and the decreasing cost of renewable energy systems. The driving motivator of this thesis is the investigation of an alternative power system architecture coupled with, specifically, a designed transactive energy market and system control strategies to provide an electrical network in which end-users benefit through their grid connection and have the ability to buy and sell excess and deficiencies of energy as required. The enpowerment and incorporation of end-users into a transactive energy market will increase the level of competition for both the purchase and sale of electrical energy, resulting in both lower purchasing costs and increased rates of return on renewable energy systems. Whilst there exists literature investigating specific distribution network architectures, primarily the microgrid, a system wide approach for future power grids has yet to be settled upon. Further, the transactive energy market concept has gained significant research interest over recent years with applications to traditional networks and within microgrid applications. This thesis presents an alternative power system architecture, the Intergrid, into which a specifically designed transactive energy market has been incorporated. The Intergrid is a bottom-up network architecture in which all connections are made through bidirectional power converters. Multiple localised connections are grouped, such as houses and further connected to other like-wise connected groups through additional converters. The resulting system is highly modular and provides electrical decoupling between subsystems. The symbiosis of the modular Intergrid architecture and transactive energy market is shown to be highly advantageous as the overall structure of the transactive energy market utilises the segregation and modularity of the Intergrid architecture as an instrument of arbitrage. Within the resulting system, although electrically decoupled, an overarching, interconnected market operates, providing a high level of competition. In addition, the required control and stability strategies of such a system are investigated. The discussion, derivation and a series of simulation studies, culminating in a completed system design is presented within the enclosed thesis. The results confirm the potential of the Intergrid architecture and associated control techniques to provide a functional, market driven electrical network in which consumers of all sizes actively contribute to the operation of system.