Power System Based On The Energy Of The Nonlinear Robust And Adaptive Control

The power system has a close relationship with the people's living, and plays a very important role in the development of our country's economy. With the development of large-scale power systems, it is becoming an important and urgent research topic to improve the stability and reliability of the power systems. In practical power systems, there are always uncertainties, including un-modelled dynamics, small and large disturbances, changes of parameters and network structures, etc. When the system's working point changes, the system's dynamic characteristic will change dramatically. Since linear controller is difficult to meet the control demands of power systems, the nonlinear control of power systems has drawn a great deal of attention by far.Generalized Hamiltonian systems, which developed from traditional Hamil-tonian systems, describe a kind of open systems which can have energy dissipation and energy exchange with their environment. Because of their good structures, their clear physical expression and the fact that Lyapunov candidates can be chosen from their Hamiltonian functions, generalized Hamiltonian systems have advantages over other plants in many control problems such as stability analysis and stabilization control. In recent years, Hamiltonian method, i.e., energy-based control method, has been widely used in the control of power system. As well known, the power system is a complex system with energy production, transmission and consumption. Since energy balance is a key fact in the power system, it is very natural to take the system's energy function as the Lyapnov function in the control design. Study shows that the generalized Hamiltonian system provides not only a proper mathematical description for power systems, but also a new and effective tool for investigating the control of power systems.At present, the Hamiltonian control method is mainly used to deal with the control of power systems with certain and undisturbed models. However, since there are always uncertainties and disturbances in practical power systems, robust and adaptive control has to be taken into account in practical control design of power systems.This dissertation first investigates the control of dissipative Hamiltonian systems with perturbations in the structure matrix. A feedback controller and an L₂ controller are designed, respectively. When the systems have both parameter perturbations and disturbances, an adaptive robust controller is proposed. Then, the energy-based robust control of power systems is investigated, and robust controllers are designed for single-machine infinite-bus power system, synchronous generators with steam valve control, fifth-order model of synchronous generators and synchronous generators with the SMES unit,...